Author: "Helene Roussel" / Topic: space and planetary science - Searchworks@Jio Institute Digital Library Search Results

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51 results on '"Helene Roussel"'

1. GASTON: Galactic Star Formation with NIKA2 – evidence for the mass growth of star-forming clumps

Author: Herve Aussel, Florian Kéruzoré, K. F. Schuster, Albrecht Sievers, Bilal Ladjelate, Florian Ruppin, Carsten Kramer, Nicolas Ponthieu, Isabelle Ristorcelli, P. A. R. Ade, Andrew Rigby, E. J. Watkins, Philippe André, S. Leclercq, Paula Gaspar García, Guilaine Lagache, Martino Calvo, R. Adam, Philip Daniel Mauskopf, Andrea Bracco, V. Revéret, C. Romero, Carole Tucker, J. Goupy, Alain Benoit, A. Andrianasolo, F. Mayet, L. Perotto, Shibo Shu, A. Catalano, Malcolm Anderson, M. De Petris, F.-X. Désert, Aurore Bacmann, Alessandro Monfardini, Alicia Gomez, Giampaolo Pisano, J. F. Macías-Pérez, Alexandre Beelen, O. Bourrion, E. F. C. Driessen, Nicolas Peretto, Helene Roussel, S. Berta, Simon Doyle, J.-F. Lestrade, A. Ritacco, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Hélium : du fondamental aux applications (NEEL - HELFA), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Cryogénie (NEEL - Cryo), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique de l'ENS - ENS Paris (LPENS), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Département de Physique de l'ENS-PSL, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Ritacco, A. [0000-0003-0162-8206], Rigby, A. J. [0000-0002-3351-2200], Peretto, N. [0000-0002-6893-602X], Bacmann, A. [0000-0003-1263-4986], Science and Technology Facilities Council (STFC), National Aeronautics and Space Administration (NASA), European Research Council (ERC), European Commission (EC), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-École normale supérieure - Paris (ENS Paris), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Laboratoire de physique de l'ENS - ENS Paris (LPENS (UMR_8023)), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
Subjects: ISM: structure, Population, Continuum (design consultancy), Galaxy: disc, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, evolution [ISM], 01 natural sciences, ISM: evolution, surveys, 0103 physical sciences, stars: formation, stars: massive, massive [Stars], Astrophysics::Solar and Stellar Astrophysics, education, 010303 astronomy & astrophysics, QC, Astrophysics::Galaxy Astrophysics, formation [Stars], QB, Physics, [PHYS]Physics [physics], education.field_of_study, 010308 nuclear & particles physics, Star formation, Order (ring theory), Astronomy and Astrophysics, Galactic plane, Astrophysics - Astrophysics of Galaxies, Galaxy, Stars, disc [Galaxy], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Ophiuchus, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Determining the mechanism by which high-mass stars are formed is essential for our understanding of the energy budget and chemical evolution of galaxies. By using the New IRAM KIDs Array 2 (NIKA2) camera on the Institut de Radio Astronomie Millim\'etrique (IRAM) 30-m telescope, we have conducted high-sensitivity and large-scale mapping of a fraction of the Galactic plane in order to search for signatures of the transition between the high- and low-mass star-forming modes. Here, we present the first results from the Galactic Star Formation with NIKA2 (GASTON) project, a Large Programme at the IRAM 30-m telescope which is mapping $\approx$2 deg$^2$ of the inner Galactic plane (GP), centred on $\ell$=23.9$^\circ$, $b$=0.05$^\circ$, as well as targets in Taurus and Ophiuchus in 1.15 and 2.00 mm continuum wavebands. In this paper we present the first of the GASTON GP data taken, and present initial science results. We conduct an extraction of structures from the 1.15 mm maps using a dendrogram analysis and, by comparison to the compact source catalogues from Herschel survey data, we identify a population of 321 previously-undetected clumps. Approximately 80 per cent of these new clumps are 70 $\mu$m-quiet, and may be considered as starless candidates. We find that this new population of clumps are less massive and cooler, on average, than clumps that have already been identified. Further, by classifying the full sample of clumps based upon their infrared-bright fraction - an indicator of evolutionary stage - we find evidence for clump mass growth, supporting models of clump-fed high-mass star formation., Comment: 21 pages, 15 figures, 5 tables. Accepted by MNRAS
Published: 2021

2. Modeling Dust and Starlight in Galaxies Observed by Spitzer and Herschel: The KINGFISH Sample

Author: Fabian Walter, G. Aniano, Leslie K. Hunt, Charles W. Engelbracht, Karin Sandstrom, Ramin A. Skibba, J. Hinz, E. Montiel, Benjamin D. Johnson, M. Relaño, I. De Looze, Karl D. Gordon, J. Donovan Meyer, J. D. T. Smith, Jin Koda, Daniela Calzetti, Adam Miller, R. C. Kennicutt, Lee Armus, George Helou, Daniel A. Dale, Marc Sauvage, H.-W. Rix, Adam K. Leroy, Eric J. Murphy, B. T. Draine, Alison F. Crocker, Helene Roussel, Maud Galametz, Mark G. Wolfire, Médéric Boquien, Eva Schinnerer, Alberto D. Bolatto, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and USA
Subjects: Astrophysical dust processes (99), Infrared galaxies, 010504 meteorology & atmospheric sciences, Infrared, Metallicity, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Luminosity, Photometry (optics), Spitzer Space Telescope, Interstellar medium, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Infrared galaxies (790), 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Cosmic dust, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, Polycyclic aromatic hydrocarbons (1280), Astrophysics - Astrophysics of Galaxies, Polycyclic aromatic hydrocarbons, Galaxy, Starlight, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, Astrophysical dust processes, Interstellar medium (847)
Abstract: Dust and starlight are modeled for the KINGFISH project galaxies. With data from 3.6 micron to 500 micron, models are strongly constrained. For each pixel in each galaxy we estimate (1) dust surface density; (2) q_PAH, the dust mass fraction in PAHs; (3) distribution of starlight intensities heating the dust; (4) luminosity emitted by the dust; and (5) dust luminosity from regions with high starlight intensity. The models successfully reproduce both global and resolved spectral energy distributions. We provide well-resolved maps for the dust properties. As in previous studies, we find q_PAH to be an increasing function of metallicity, above a threshold Z/Z_sol approx 0.15. Dust masses are obtained by summing the dust mass over the map pixels; these "resolved" dust masses are consistent with the masses inferred from model fits to the global photometry. The global dust-to-gas ratios obtained from this study correlate with galaxy metallicities. Systems with Z/Z_sol > 0.5 have most of their refractory elements locked up in dust, whereas when Z/Z_sol < 0.3 most of these elements tend to remain in the gas phase. Within galaxies, we find that q_PAH is suppressed in regions with unusually warm dust with nu L_nu(70 um) > 0.4L_dust. With knowledge of one long-wavelength flux density ratio (e.g., f_{160}/f_{500}), the minimum starlight intensity heating the dust (U_min) can be estimated to within ~50%. For the adopted dust model, dust masses can be estimated to within ~0.07 dex accuracy using the 500 micron luminosity nu L_nu(500) alone. There are additional systematic errors arising from the choice of dust model, but these are hard to estimate. These calibrated prescriptions may be useful for studies of high-redshift galaxies., ApJ, accepted
Published: 2019
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3. Mapping the cold dust temperatures and masses of nearby KINGFISH galaxies withHerschel

Author: G. Aniano, Daniela Calzetti, Lee Armus, Frederick M. Walter, Joannah L. Hinz, Fatemeh Tabatabaei, Helene Roussel, Mark G. Wolfire, C. D. Wilson, Charles W. Engelbracht, J. Donovan Meyer, Maud Galametz, Daniel A. Dale, Alison F. Crocker, Frank Bertoldi, M. Albrecht, Ramin A. Skibba, Achim Weiss, Robert C. Kennicutt, Kevin V. Croxall, and Bruce T. Draine
Subjects: Physics, Line-of-sight, 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Galaxy, Wavelength, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Emissivity, Black-body radiation, Angular resolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Noise (radio), Bar (unit)
Abstract: Taking advantage of the sensitivity and angular resolution of the Herschel Space Observatory at far-infrared and submm wavelengths, we aim to characterize the physical properties of cold dust within nearby galaxies and study the robustness of the parameters we derive using different modified blackbody models. For a pilot subsample of the KINGFISH program, we perform 2 temperature fits of the Spitzer and Herschel photometric data (24 to 500um), with a warm and a cold component, globally and in each resolution element.At global scales, we observe ranges of values for beta_c(0.8 to 2.5) and Tc(19.1 to 25.1K).We compute maps of our parameters with beta fixed or free to test the robustness of the temperature and dust surface density maps we deduce. When the emissivity is fixed, we observe temperature gradients as a function of radius.When the emissivity is fitted as a free parameter, barred galaxies tend to have uniform fitted emissivities.Gathering resolved elements in a Tc-beta_c diagram underlines an anti-correlation between the two parameters.It remains difficult to assess whether the dominant effect is the physics of dust grains, noise, or mixing along the line of sight and in the beam. We finally observe in both cases that the dust column density peaks in central regions of galaxies and bar ends (coinciding with molecular gas density enhancements usually found in these locations).We also quantify how the total dust mass varies with our assumptions about the emissivity index as well as the influence of the wavelength coverage used in the fits. We show that modified blackbody fits using a shallow emissivity (beta_c < 2.0) lead to significantly lower dust masses compared to the beta_c < 2.0 case, with dust masses lower by up to 50% if beta_c=1.5 for instance.The working resolution affects our total dust mass estimates: masses increase from global fits to spatially-resolved fits.
Published: 2012

4. A census of dense cores in the Aquila cloud complex: SPIRE/PACS observations from the Herschel Gould Belt survey⋆,⋆⋆,⋆⋆⋆

Author: Vera Könyves, P. Didelon, Matthew James Griffin, T. Hill, P. Palmeirim, Alexander Men'shchikov, Doris Arzoumanian, Stefano Pezzuto, Sarah Sadavoy, Kenneth A. Marsh, Glenn J. White, Ph. André, E. Schisano, Yoshito Shimajiri, J. Di Francesco, L. Spinoglio, Sylvain Bontemps, Peter G. Martin, Milena Benedettini, J.-Ph. Bernard, Nicola Schneider, Derek Ward-Thompson, Kazi L.J. Rygl, Jason M. Kirk, Frédérique Motte, A. Roy, Anaëlle Maury, Bilal Ladjelate, Helene Roussel, Q. Nguyen Luong, Nicolas Peretto, Davide Elia, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, FORMATION STELLAIRE 2015, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Department of Physics and Astronomy [Victoria], University of Victoria [Canada] (UVIC), School of Physics and Astronomy [Cardiff], Cardiff University, Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Joint ALMA Observatory (JAO), National Radio Astronomy Observatory (NRAO)-European Southern Observatory (ESO), Jeremiah Horrocks Institute for Mathematics, Physics and Astronomy [Preston], University of Central Lancashire [Preston] (UCLAN), Canadian Institute for Theoretical Astrophysics (CITA), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Bologna (OABO), Department of Physics and Astronomy [Milton Keynes], The Open University [Milton Keynes] (OU), ANR-11-BS56-0010,STARFICH,Vers une vision unifiée de la formation stellaire dans les galaxies : Origine de la structure filamentaire du milieu interstellaire, des cœurs pré-stellaires et des amas protostellaires vus avec Herschel(2011), European Project: 291294,EC:FP7:ERC,ERC-2011-ADG_20110209,ORISTARS(2012), European Project: 267934,EC:FP7:ERC,ERC-2010-AdG_20100224,MISTIC(2011), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], San Pedro de Atacama Celestial Explorations (SPACE), San Pedro de Atacama Celestial Explorations, University of California [Los Angeles] (UCLA), University of California, Service des Photons, Atomes et Molécules (SPAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Procédés, Matériaux et Energie Solaire (PROMES), Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), SLAC National Accelerator Laboratory (SLAC), Stanford University, Stanford Linear Accelerator Center (SLAC), Stanford University [Stanford], Smithsonian Institution-Harvard University [Cambridge], Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO)-National Radio Astronomy Observatory (NRAO), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Harvard University-Smithsonian Institution, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), ITA, GBR, FRA, DEU, CAN, CHL, JPN, and NLD
Subjects: Initial mass function, ISM: structure, Stars: formation, Young stellar object, FOS: Physical sciences, Budget control, F500, Efficiency, Astrophysics, Surveys, Population statistics, ISM : clouds, 7. Clean energy, Submillimeter: isms, Gravitation, ISM: individual objects, Functions, Protostar, Spatial distribution, QB, Physics, Star formation, Information dissemination, Molecular cloud, Astronomy and Astrophysics, Stars, Astrophysics - Astrophysics of Galaxies, Spire, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Coremaking, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA]
Abstract: We present and discuss the results of the Herschel Gould Belt survey (HGBS) observations in an 11 deg2 area of the Aquila molecular cloud complex at d 260 pc, imaged with the SPIRE and PACS photometric cameras in parallel mode from 70 μm to 500 μm. Using the multi-scale, multi-wavelength source extraction algorithm getsources, we identify a complete sample of starless dense cores and embedded (Class 0-I) protostars in this region, and analyze their global properties and spatial distributions. We find a total of 651 starless cores, 60% ± 10% of which are gravitationally bound prestellar cores, and they will likely form stars inthe future. We also detect 58 protostellar cores. The core mass function (CMF) derived for the large population of prestellar cores is very similar in shape to the stellar initial mass function (IMF), confirming earlier findings on a much stronger statistical basis and supporting the view that there is a close physical link between the stellar IMF and the prestellar CMF. The global shift in mass scale observed between the CMF and the IMF is consistent with a typical star formation efficiency of 40% at the level of an individual core. By comparing the numbers of starless cores in various density bins to the number of young stellar objects (YSOs), we estimate that the lifetime of prestellar cores is 1 Myr, which is typically 4 times longer than the core free-fall time, and that it decreases with average core density. We find a strong correlation between the spatial distribution of prestellar cores and the densest filaments observed in the Aquila complex. About 90% of the Herschel-identified prestellar cores are located above a background column density corresponding to AV 7, and 75% of them lie within filamentary structures with supercritical masses per unit length ≳16 M☉/pc. These findings support a picture wherein the cores making up the peak of the CMF (and probably responsible for the base of the IMF) result primarily from the gravitational fragmentation of marginally supercritical filaments. Given that filaments appear to dominate the mass budget of dense gas at AV> 7, our findings also suggest that the physics of prestellar core formation within filaments is responsible for a characteristic "efficiency" {SFR/M_dense ̃ 5+2-2 × 10-8 yr-1} for the star formation process in dense gas. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Figures 18, 19, and Appendices are available in electronic form at http://www.aanda.orgHerschel column density and temperature maps (FITS format) and full Tables A.1 and A.2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/584/A91
Published: 2015

5. KINGFISH—Key Insights on Nearby Galaxies: A Far-Infrared Survey withHerschel: Survey Description and Image Atlas1

Author: J. D. T. Smith, Bruce T. Draine, Karl D. Gordon, Leslie K. Hunt, Charles W. Engelbracht, Brent Groves, Marc Sauvage, Benjamin D. Johnson, Lee Armus, George Helou, Jin Koda, Bernhard R. Brandl, Kevin V. Croxall, Stefano Zibetti, Yongbao Li, P. Beirao, P. N. Appleton, Maud Galametz, Karin Sandstrom, Helene Roussel, J. L. Hinz, Cai-Na Hao, E. Montiel, Ramin A. Skibba, Alberto D. Bolatto, L. Vigroux, Alison F. Crocker, Sundar Srinivasan, C. D. Wilson, Eva Schinnerer, Oliver Krause, Daniela Calzetti, Frederick M. Walter, H-W. Rix, J. Dononvan Meyer, Sharon E. Meidt, Mark G. Wolfire, Daniel A. Dale, Nurur Rahman, Adam K. Leroy, Eric J. Murphy, Robert C. Kennicutt, and G. Aniano
Subjects: Physics, Data products, Star formation, media_common.quotation_subject, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Galaxy, Universe, Interstellar medium, medicine.anatomical_structure, Far infrared, Space and Planetary Science, Atlas (anatomy), medicine, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, media_common, Line (formation)
Abstract: The KINGFISH project (Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel) is an imaging and spectroscopic survey of 61 nearby (d < 30 Mpc) galaxies, chosen to cover a wide range of galaxy properties and local interstellar medium (ISM) environments found in the nearby Universe. Its broad goals are to characterize the ISM of present-day galaxies, the heating and cooling of their gaseous and dust components, and to better understand the physical processes linking star formation and the ISM. KINGFISH is a direct descendant of the Spitzer Infrared Nearby Galaxies Survey (SINGS), which produced complete Spitzer imaging and spectroscopic mapping and a comprehensive set of multi-wavelength ancillary observations for the sample. The Herschel imaging consists of complete maps for the galaxies at 70, 100, 160, 250, 350, and 500 microns. The spectal line imaging of the principal atomic ISM cooling lines ([OI]63um, [OIII]88um, [NII]122,205um, and [CII]158um) covers the subregions in the centers and disks that already have been mapped in the mid-infrared with Spitzer. The KINGFISH and SINGS multi-wavelength datasets combined provide panchromatic mapping of the galaxies sufficient to resolve individual star-forming regions, and tracing the important heating and cooling channels of the ISM, across a wide range of local extragalactic ISM environments. This paper summarizes the scientific strategy for KINGFISH, the properties of the galaxy sample, the observing strategy, and data processing and products. It also presents a combined Spitzer and Herschel image atlas for the KINGFISH galaxies, covering the wavelength range 3.6 -- 500 microns. All imaging and spectroscopy data products will be released to the Herschel user generated product archives.
Published: 2011

6. Investigations of dust heating in M81, M83 and NGC 2403 with the Herschel Space Observatory

Author: Marc Sauvage, Haley Louise Gomez, S. C. Madden, Bernhard Schulz, Helene Roussel, David L. Clements, Vianney Lebouteiller, Luca Cortese, Maud Galametz, George J. Bendo, Aliakbar Dariush, Christine D. Wilson, Maarten Baes, L. Spinoglio, Matthew Smith, A. Cooray, K. Foyle, Nanyao Y. Lu, M. J. Page, Erin Mentuch, B. O'Halloran, A. Remy, Alessandro Boselli, and Michael Pohlen
Subjects: Physics, Spiral galaxy, 010308 nuclear & particles physics, Star formation, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Radiation, 01 natural sciences, Galaxy, Starlight, Stars, Spitzer Space Telescope, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Surface brightness, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We use Spitzer Space Telescope and Herschel Space Observatory far-infrared data along with ground-based optical and near-infrared data to understand how dust heating in the nearby face-on spiral galaxies M81, M83, and NGC 2403 is affected by the starlight from all stars and by the radiation from star forming regions. We find that 70/160 micron surface brightness ratios tend to be more strongly influenced by star forming regions. However, the 250/350 micron and 350/500 micron surface brightness ratios are more strongly affected by the light from the total stellar populations, suggesting that the dust emission at >250 microns originates predominantly from a component that is colder than the dust seen at
Published: 2011

7. On the origin of M81 group extended dust emission

Author: Bernhard Schulz, L. Spinoglio, Maud Galametz, Andreas Papageorgiou, Jason Glenn, Jonathan Ivor Davies, Marc Sauvage, N. Lu, Matthew Joseph Griffin, Eli Dwek, Robbie Richard Auld, D. Elbaz, Seb Oliver, M. J. Barlow, Herve Wozniak, Laure Ciesla, B. O'Halloran, L. R. Levenson, Ismael Perez-Fournon, Alessandro Boselli, A. Rykala, M. Bradford, M. Trichas, Christine D. Wilson, Frédéric Galliano, Walter Kieran Gear, Naseem Rangwala, George J. Bendo, Maximilien R. P. Schirm, Maarten Baes, Mat Page, A. Cooray, Jamie Stevens, Mattia Vaccari, Koryo Okumura, N. Sacchi, Sundar Srinivasan, T. J. Parkin, Diane Cormier, Suzanne C. Madden, Pasquale Panuzzo, N. Castro-Rodriguez, V. Buat, E. E. Rigby, Michael Pohlen, Kate Gudrun Isaak, M. Symeonidis, Matthew Smith, Helene Roussel, David L. Clements, Luca Cortese, L. Vigroux, James J. Bock, Stephane Charlot, Sacha Hony, Gillian S. Wright, Haley Louise Gomez, Pierre Chanial, Stephen Anthony Eales, and Werner W. Zeilinger
Subjects: Physics, Infrared, Astrophysics::High Energy Astrophysical Phenomena, Astronomy and Astrophysics, Minute of arc, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Galaxy, Wavelength, Space and Planetary Science, Group (periodic table), Cirrus, Optical emission spectroscopy, Astrophysics::Galaxy Astrophysics, Dust emission
Abstract: Galactic cirrus emission at far-infrared wavelengths affects many extragalactic observations. Separating this emission from that associated with extragalactic objects is both important and difficult. In this paper we discuss a particular case, the M81 group, and the identification of diffuse structures prominent in the infrared, but also detected at optical wavelengths. The origin of these structures has previously been controversial, ranging from them being the result of a past interaction between M81 and M82 or due to more local Galactic emission. We show that over of order a few arcminute scales the far-infrared (Herschel 250 &\mu&m) emission correlates spatially very well with a particular narrow velocity (2-3 km/s) component of the Galactic HI. We find no evidence that any of the far-infrared emission associated with these features actually originates in the M81 group. Thus we infer that the associated diffuse optical emission must be due to galactic light back scattered off dust in our galaxy. Ultra-violet observations pick out young stellar associations around M81, but no detectable far-infrared emission. We consider in detail one of the Galactic cirrus features, finding that the far-infrared HI relation breaks down below arc minute scales and that at smaller scales there can be quite large dust temperature variations.
Published: 2010

8. The Herschel Reference Survey

Author: Jason Glenn, E. Dwek, George J. Bendo, Jamie Stevens, Alessandro Boselli, N. Sacchi, Mat Page, Walter Kieran Gear, L. Vigroux, Ismael Perez-Fournon, Maximilien R. P. Schirm, K. Okumura, P. Chanial, K. G. Isaak, A. Rykala, Diane Cormier, James J. Bock, Jonathan Ivor Davies, E. E. Rigby, Marc Sauvage, Stephane Charlot, Matthew Smith, Michael Pohlen, N. Castro-Rodriguez, G. Wright, L. Spinoglio, N. Rangwala, Louis Levenson, Robbie Richard Auld, D. Elbaz, Matthew Joseph Griffin, Helene Roussel, David L. Clements, Christine D. Wilson, B. O'Halloran, Benjamin L. Schulz, Luca Cortese, V. Buat, Werner W. Zeilinger, Frédéric Galliano, Haley Louise Gomez, Stephen Anthony Eales, Maarten Baes, M. Bradford, P. Panuzzo, Nanyao Y. Lu, M. J. Barlow, M. Symeonidis, Suzanne C. Madden, S. J. Oliver, Sacha Hony, T. J. Parkin, Herve Wozniak, Andreas Papageorgiou, Maud Galametz, and Mattia Vaccari
Subjects: Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Stellar mass, media_common.quotation_subject, FOS: Physical sciences, Astronomy and Astrophysics, Sample (statistics), Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Virgo Cluster, Galaxy, Universe, Interstellar medium, Stars, Space and Planetary Science, Range (statistics), Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics, media_common
Abstract: The Herschel Reference Survey is a guaranteed time Herschel key project and will be a benchmark study of dust in the nearby universe. The survey will complement a number of other Herschel key projects including large cosmological surveys that trace dust in the distant universe. We will use Herschel to produce images of a statistically-complete sample of 323 galaxies at 250, 350 and 500 micron. The sample is volume-limited, containing sources with distances between 15 and 25 Mpc and flux limits in the K-band to minimize the selection effects associated with dust and with young high-mass stars and to introduce a selection in stellar mass. The sample spans the whole range of morphological types (ellipticals to late-type spirals) and environments (from the field to the centre of the Virgo Cluster) and as such will be useful for other purposes than our own. We plan to use the survey to investigate (i) the dust content of galaxies as a function of Hubble type, stellar mass and environment, (ii) the connection between the dust content and composition and the other phases of the interstellar medium and (iii) the origin and evolution of dust in galaxies. In this paper, we describe the goals of the survey, the details of the sample and some of the auxiliary observing programs that we have started to collect complementary data. We also use the available multi-frequency data to carry out an analysis of the statistical properties of the sample., Comment: Accepted for publication on PASP
Published: 2010

9. HERACLES: THE HERA CO LINE EXTRAGALACTIC SURVEY

Author: K. F. Schuster, Elias Brinks, Fabian Walter, W. J. G. de Blok, Achim Weiss, R. C. Kennicutt, Carsten Kramer, Helmut Wiesemeyer, Frank Bigiel, Adam Leroy, Helene Roussel, and Antonio Usero
Subjects: Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Metallicity, Milky Way, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Radius, HERA, Galaxy, law.invention, Telescope, Space and Planetary Science, law, Irregular galaxy, Astrophysics::Galaxy Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics, Line (formation)
Abstract: We present the HERA CO-Line Extragalactic Survey (HERACLES), an atlas of CO emission from 18 nearby galaxies that are also part of The HI Nearby Galaxy Survey (THINGS) and the Spitzer Infrared Nearby Galaxies Survey (SINGS). We used the HERA multi-pixel receiver on the IRAM 30-m telescope to map the CO J=2-1 line over the full optical disk (defined by the isophotal radius r_25) of each target, at 13" angular resolution and 2.6 km/s velocity resolution. Here we describe the observations and reduction of the data and show channel maps, azimuthally averaged profiles, integrated intensity maps, and peak intensity maps. The implied H2 masses range from 7 \times 10^6 to 6 \times 10^9 M_sun, with four low metallicity dwarf irregular galaxies yielding only upper limits. In the cases where CO is detected, the integrated H2-to-HI ratios range from 0.02 - 1.13 and H2-to-stellar mass ratios from 0.01 to 0.25. Exponential scale lengths of the CO emission for our targets are in the range 0.8 - 3.2 kpc, or 0.2 \pm 0.05 r_25. The intensity-weighted mean velocity of CO matches that of HI very well, with a 1\sigma scatter of only 6 km/s. The CO J=2-1 / J=1-0 line ratio varies over a range similar to that found in the Milky Way and other nearby galaxies, \sim 0.6 - 1.0, with higher values found in the centers of galaxies. The typical line ratio, \sim 0.8, could be produced by optically thick gas with an excitation temperature of \sim 10 K., Comment: 28 pages, 34 figures, published in AJ (http://adsabs.harvard.edu/abs/2009AJ....137.4670L)
Published: 2009

10. Spectral Mapping Reconstruction of Extended Sources

Author: Lee Armus, Brent A. Buckalew, Helene Roussel, Kartik Sheth, Daniel A. Dale, George Helou, Thomas H. Jarrett, J. D. T. Smith, and R. C. Kennicutt
Subjects: Physics, Field (physics), business.industry, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Flux, Astronomy and Astrophysics, Reconstruction algorithm, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Optics, Spitzer Space Telescope, Space and Planetary Science, Calibration, Cube, business, Spectroscopy, Spectrograph
Abstract: Three dimensional spectroscopy of extended sources is typically performed with dedicated integral field spectrographs. We describe a method of reconstructing full spectral cubes, with two spatial and one spectral dimension, from rastered spectral mapping observations employing a single slit in a traditional slit spectrograph. When the background and image characteristics are stable, as is often achieved in space, the use of traditional long slits for integral field spectroscopy can substantially reduce instrument complexity over dedicated integral field designs, without loss of mapping efficiency -- particularly compelling when a long slit mode for single unresolved source followup is separately required. We detail a custom flux-conserving cube reconstruction algorithm, discuss issues of extended source flux calibration, and describe CUBISM, a tool which implements these methods for spectral maps obtained with ther Spitzer Space Telescope's Infrared Spectrograph., Comment: 11 pages, 8 figures, accepted by PASP
Published: 2007

11. Cool dust heating and temperature mixing in nearby star-forming galaxies

Author: Jin Koda, R. C. Kennicutt, Marc Sauvage, Karin Sandstrom, Maud Galametz, Kevin V. Croxall, Karl D. Gordon, A. Gil de Paz, Médéric Boquien, Daniel A. Dale, Alberto D. Bolatto, Christine D. Wilson, George Helou, Simone Bianchi, Leslie K. Hunt, Juan-Carlos Muñoz-Mateos, G. Aniano, Daniela Calzetti, Bruce T. Draine, Stefano Zibetti, Joannah L. Hinz, Helene Roussel, L. Vigroux, INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), and ITA
Subjects: HERSCHEL REFERENCE SURVEY, Brightness, DWARF GALAXIES, INFRARED-EMISSION, FOS: Physical sciences, SPECTRAL ENERGY-DISTRIBUTIONS, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Radiation, 60 MU-M, Emissivity, Astrophysics::Solar and Stellar Astrophysics, COLD DUST, SMALL-MAGELLANIC-CLOUD, Astrophysics::Galaxy Astrophysics, SUBMILLIMETER EXCESS EMISSION, Physics, Range (particle radiation), ISM [galaxies], extinction, Astronomy and Astrophysics, Radius, Astrophysics - Astrophysics of Galaxies, Galaxy, Interstellar medium, Physics and Astronomy, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), galaxies: star formation, Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics, dust, star formation [galaxies], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], SPIRAL GALAXIES, INTERSTELLAR DUST, galaxies: ISM
Abstract: Physical conditions of the interstellar medium in galaxies are closely linked to the ambient radiation field and the heating of dust grains. In order to characterize dust properties in galaxies over a wide range of physical conditions, we present here the radial surface brightness profiles of the entire sample of 61 galaxies from Key Insights into Nearby Galaxies: Far-Infrared Survey with Herschel (KINGFISH). The main goal of our work is the characterization of the grain emissivities, dust temperatures, and interstellar radiation fields responsible for heating the dust. After fitting the dust and stellar radial profiles with exponential functions, we fit the far-infrared spectral energy distribution (SED) in each annular region with single-temperature modified black bodies using both variable (MBBV) and fixed (MBBF) emissivity indices beta, as well as with physically motivated dust models. Results show that while most SED parameters decrease with radius, the emissivity index beta also decreases with radius in some galaxies, but in others is increasing, or rising in the inner regions and falling in the outer ones. Despite the fixed grain emissivity (average beta~ 2.1) of the physically-motivated models, they are well able to accommodate flat spectral slopes with beta, 28 pages, 20 figures, accepted for publication in A&A
Published: 2015

12. Warm Dust and Spatially Variable Polycyclic Aromatic Hydrocarbon Emission in the Dwarf Starburst Galaxy NGC 1705

Author: Daniela Calzetti, George J. Bendo, Karl D. Gordon, David Hollenbach, Marcia J. Rieke, John-David T. Smith, George Helou, Claus Leitherer, Daniel A. Dale, Bruce T. Draine, Fabian Walter, Aigen Li, Eric J. Murphy, George H. Rieke, Charles W. Engelbracht, Robert C. Kennicutt, Brent A. Buckalew, Helene Roussel, Michele D. Thornley, Lee Armus, Michael W. Regan, John M. Cannon, Thomas H. Jarrett, Kartik Sheth, and Martin Meyer
Subjects: Physics, Solar mass, Stellar population, Astrophysics::High Energy Astrophysical Phenomena, Metallicity, Milky Way, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Mass ratio, Galaxy, Star cluster, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, H-alpha, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We present Spitzer observations of the nearby dwarf starburst galaxy NGC 1705 obtained as part of the Spitzer Infrared Nearby Galaxies Survey. The galaxy morphology is very different shortward and longward of ~5 μm: optical and short-wavelength IRAC imaging shows an underlying red stellar population, with the central super star cluster (SSC) dominating the luminosity; longer wavelength IRAC and MIPS imaging reveals warm dust emission arising from two off-nuclear regions that are offset by ~250 pc from the SSC and that dominate the far-IR flux of the system. These regions show little extinction at optical wavelengths. The galaxy has a relatively low global dust mass (~2 × 10^5 M_☉, implying a global dust-to-gas mass ratio ~2-4 times lower than the Milky Way average, roughly consistent with the metallicity decrease). The off-nuclear dust emission appears to be powered by photons from the same stellar population responsible for the excitation of the observed Hα emission; these photons are unassociated with the SSC (although a contribution from embedded sources to the IR luminosity of the off-nuclear regions cannot be ruled out). Low-resolution IRS spectroscopy shows moderate-strength PAH emission in the 11.3 μm band in the more luminous eastern peak; no PAH emission is detected in the SSC or the western dust emission complex. There is significant diffuse emission in the IRAC 8 μm band after starlight has been removed by scaling shorter wavelength data; the fact that IRS spectroscopy shows spatially variable PAH emission strengths compared to the local continuum within this diffuse gas suggests caution in the interpretation of IRAC diffuse 8 μm emission as arising from PAH carriers alone. The nebular metallicity of NGC 1705 falls at the transition level of ~0.35 Z_☉ found by Engelbracht and collaborators, below which PAH emission is difficult to detect; the fact that a system at this metallicity shows spatially variable PAH emission demonstrates the complexity of interpreting diffuse 8 μm emission in galaxies. NGC 1705 deviates significantly from the canonical far-infrared versus radio correlation, having significant far-infrared emission but no detected radio continuum.
Published: 2006

13. THE PHYSICAL CHARACTERISTICS OF THE GAS IN THE DISK OF CENTAURUS A USING THE HERSCHEL SPACE OBSERVATORY

Author: Christine D. Wilson, I. De Looze, Médéric Boquien, L. Spinoglio, Alessandro Boselli, M. R. P. Schirm, Matthew Smith, Helene Roussel, Maarten Baes, Vianney Lebouteiller, Suzanne C. Madden, D. Cormier, O. Ł. Karczewski, Maud Galametz, T. J. Parkin, McMaster University [Hamilton, Ontario], Sterrenkundig Observatorium, Universiteit Gent = Ghent University (UGENT), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Universität Heidelberg [Heidelberg] = Heidelberg University, University of Cambridge [UK] (CAM), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), AUTRES, Antarctic Research a European Network for Astrophysics (ARENA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Universiteit Gent, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Universität Heidelberg [Heidelberg], Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: ULTRALUMINOUS INFRARED GALAXIES, C-II, Centaurus A, Doubly ionized oxygen, MU-M, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, PHOTODISSOCIATION REGIONS, 01 natural sciences, PHOTON-DOMINATED REGIONS, 0103 physical sciences, STAR-FORMING GALAXIES, EARLY-TYPE GALAXIES, Emission spectrum, Spectroscopy, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, QB, Physics, individual (Centaurus A) [galaxies], Spiral galaxy, ISM [galaxies], INTERSTELLAR-MEDIUM, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, ISM [infrared], Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, MOLECULAR GAS, Interstellar medium, Physics and Astronomy, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), NGC 5128, Elliptical galaxy, lines and bands [ISM]
Abstract: We search for variations in the disk of Centaurus A of the emission from atomic fine structure lines using Herschel PACS and SPIRE spectroscopy. In particular we observe the [C II](158 $\mu$m), [N II](122 and 205 $\mu$m), [O I](63 and 145 $\mu$m) and [O III](88 $\mu$m) lines, which all play an important role in cooling the gas in photo-ionized and photodissociation regions. We determine that the ([C II]+[O I]$_{63}$)/$F_{TIR}$ line ratio, a proxy for the heating efficiency of the gas, shows no significant radial trend across the observed region, in contrast to observations of other nearby galaxies. We determine that 10 - 20% of the observed [C II] emission originates in ionized gas. Comparison between our observations and a PDR model shows that the strength of the far-ultraviolet radiation field, $G_0$, varies between $10^{1.75}$ and $10^{2.75}$ and the hydrogen nucleus density varies between $10^{2.75}$ and $10^{3.75}$ cm$^{-3}$, with no significant radial trend in either property. In the context of the emission line properties of the grand-design spiral galaxy M51 and the elliptical galaxy NGC 4125, the gas in Cen A appears more characteristic of that in typical disk galaxies rather than elliptical galaxies., Comment: Accepted for publication in the Astrophysical Journal. 22 pages, 10 figures, 5 tables
Published: 2014

14. Reconstructing the density and temperature structure of prestellar cores from $Herschel$ data: A case study for B68 and L1689B

Author: Dimitris Stamatellos, Kazi L.J. Rygl, Stefano Pezzuto, T. Hill, Frédérique Motte, A. Abergel, A. Rivera-Ingraham, Glenn J. White, Ph. André, Doris Arzoumanian, Helene Roussel, Alexander Men'shchikov, Vera Könyves, Nicolas Peretto, Kenneth A. Marsh, Derek Ward-Thompson, L. Spinoglio, Milena Benedettini, Matthew Joseph Griffin, M. Attard, P. Palmeirim, Nicola Schneider, Jason M. Kirk, A. Roy, Q. Nguyen Luong, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Cardiff], Cardiff University, Oristars, Oristars (291294), European Project: 291294,EC:FP7:ERC,ERC-2011-ADG_20110209,ORISTARS(2012), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), FORMATION STELLAIRE 2014, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), Antarctic Research a European Network for Astrophysics (ARENA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Opacity, Extinction (astronomy), FOS: Physical sciences, F500, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Lambda, ISM: individual objects: B68, ISM: individual objects: L1689B, Radiative transfer, Astrophysics::Solar and Stellar Astrophysics, Continuum (set theory), Astrophysics::Galaxy Astrophysics, QB, Physics, Line-of-sight, stars: formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], extinction, Drop (liquid), Center (category theory), Astronomy and Astrophysics, submillimeter: general, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, dust, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Utilizing multi-wavelength dust emission maps acquired with $Herschel$, we reconstruct local volume density and dust temperature profiles for the prestellar cores B68 and L1689B using inverse-Abel transform based technique. We present intrinsic radial dust temperature profiles of starless cores directly from dust continuum emission maps disentangling the effect of temperature variations along the line of sight which was previously limited to the radiative transfer calculations. The reconstructed dust temperature profiles show a significant drop in core center, a flat inner part, and a rising outward trend until the background cloud temperature is reached. The central beam-averaged dust temperatures obtained for B68 and L1689B are 9.3 $\pm$ 0.5 K and 9.8 $\pm$0.5 K, respectively, which are lower than the temperatures of 11.3 K and 11.6 K obtained from direct SED fitting. The best mass estimates derived by integrating the volume density profiles of B68 and L1689B are 1.6 M_sol and 11 M_sol, respectively. Comparing our results for B68 with the near-infrared extinction studies, we find that the dust opacity law adopted by the HGBS project, $\kappa_{\lambda} =0.1(\lambda/300 \mu m)^{-2}$, agrees to within 50% with the dust extinction constraints, Comment: 10 pages, 7 figures, Accepted for publication to A&A
Published: 2014

15. Pillars and globules at the edges of H ii regions

Author: Timea Csengeri, P. Didelon, L. Spinoglio, Annie Zavagno, J. P. Bernard, A. P. Marston, Helene Roussel, Edouard Audit, L. D. Anderson, Nicola Schneider, J. Di Francesco, Martin Hennemann, Frédérique Motte, Pascal Tremblin, Vincent Minier, Tracey Hill, Sylvain Bontemps, Jonathan Williams, Glenn J. White, Q. Nguyen Luong, Ph. André, Davide Elia, T. Sousbie, Vera Könyves, Nicolas Peretto, Doris Arzoumanian, A. Rivera-Ingraham, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Maison de la Simulation (MDLS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de Recherche en Informatique et en Automatique (Inria)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, FORMATION STELLAIRE 2013, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Antarctic Research a European Network for Astrophysics (ARENA), Engineering Department, University of Cambridge [UK] (CAM), Medical Research Council (MRC) Centre for Neuropsychiatric Genetics and Genomics, Neurosciences and Mental Health Research Institute, Department of Psychological Medicine and Neurology, School of Medicine, Cardiff University, Cardiff, UK, Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)
Subjects: HII regions, Numerical models, ISM: structure, Infrared imaging, Velocity, Shell (structure), FOS: Physical sciences, Astrophysics, Curvature, 01 natural sciences, Ionization of gases, ISM: individual objects: Rosette, ISM: individual objects: M 16, ISM: individual objects, Clouds, Ionization, H II regions, 0103 physical sciences, Shells (structures), Ism: individual objects: rosettes, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, ISM: kinematics and dynamics, Nebula, 010308 nuclear & particles physics, Turbulence, Star formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Molecular cloud, Methods:observational, Astronomy and Astrophysics, Computer simulation, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Stars, Astrophysics - Astrophysics of Galaxies, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Gases, methods: observational, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Pillars and globules are present in many high-mass star-forming regions, such as the Eagle nebula (M16) and the Rosette molecular cloud, and understanding their origin will help characterize triggered star formation. The formation mechanisms of these structures are still being debated. Recent numerical simulations have shown how pillars can arise from the collapse of the shell in on itself and how globules can be formed from the interplay of the turbulent molecular cloud and the ionization from massive stars. The goal here is to test this scenario through recent observations of two massive star-forming regions, M16 and Rosette. The column density structure of the interface between molecular clouds and H ii regions was characterized using column density maps obtained from far-infrared imaging of the Herschel HOBYS key programme. Then, the DisPerSe algorithm was used on these maps to detect the compressed layers around the ionized gas and pillars in different evolutionary states. Finally, their velocity structure was investigated using CO data, and all observational signatures were tested against some distinct diagnostics established from simulations. The column density profiles have revealed the importance of compression at the edge of the ionized gas. The velocity properties of the structures, i.e. pillars and globules, are very close to what we predict from the numerical simulations. We have identified a good candidate of a nascent pillar in the Rosette molecular cloud that presents the velocity pattern of the shell collapsing on itself, induced by a high local curvature. Globules have a bulk velocity dispersion that indicates the importance of the initial turbulence in their formation, as proposed from numerical simulations. Altogether, this study re-enforces the picture of pillar formation by shell collapse and globule formation by the ionization of highly turbulent clouds., Comment: Accepted in A&A
Published: 2013

16. COLD DUST BUT WARM GAS IN THE UNUSUAL ELLIPTICAL GALAXY NGC 4125

Author: A. Cridland, A. Cooray, K. Foyle, Walter Kieran Gear, I. De Looze, Marc Sauvage, Médéric Boquien, Suzanne C. Madden, Christine D. Wilson, A. Rémy-Ruyer, Maarten Baes, Matthew Smith, Helene Roussel, David L. Clements, Miguel Pereira-Santaella, Laure Ciesla, E. Mentuch Cooper, T. J. Parkin, George J. Bendo, Alessandro Boselli, Vianney Lebouteiller, Maud Galametz, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES)
Subjects: HERSCHEL REFERENCE SURVEY, Cosmology and Nongalactic Astrophysics (astro-ph.CO), C-II, Stellar mass, Astrophysics::High Energy Astrophysical Phenomena, MU-M, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, SCALING RELATIONS, 01 natural sciences, galaxies [infrared], STAR-FORMATION, cD, 0103 physical sciences, Galaxy formation and evolution, Astrophysics::Solar and Stellar Astrophysics, NEARBY GALAXIES, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), individual (NGC 4125) [galaxies], Astrophysics::Galaxy Astrophysics, QB, Cosmic dust, Physics, Luminous infrared galaxy, INTERSTELLAR-MEDIUM, ISM [galaxies], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Star formation, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, MOLECULAR GAS, Interstellar medium, OBSCURED GALAXIES, Astrophysics - Solar and Stellar Astrophysics, Physics and Astronomy, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Elliptical galaxy, Astrophysics::Earth and Planetary Astrophysics, MAGELLANIC-CLOUD, elliptical and lenticular [galaxies], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Data from the Herschel Space Observatory have revealed an unusual elliptical galaxy, NGC 4125, which has strong and extended submillimeter emission from cold dust but only very strict upper limits to its CO and HI emission. Depending on the dust emissivity, the total dust mass is 2-5x10^6 Msun. While the neutral gas-to-dust mass ratio is extremely low (< 12-30), including the ionized gas traced by [CII] emission raises this limit to < 39-100. The dust emission follows a similar r^{1/4} profile to the stellar light and the dust to stellar mass ratio is towards the high end of what is found in nearby elliptical galaxies. We suggest that NGC 4125 is currently in an unusual phase where evolved stars produced in a merger-triggered burst of star formation are pumping large amounts of gas and dust into the interstellar medium. In this scenario, the low neutral gas-to-dust mass ratio is explained by the gas being heated to temperatures >= 10^4 K faster than the dust is evaporated. If galaxies like NGC 4125, where the far-infrared emission does not trace neutral gas in the usual manner, are common at higher redshift, this could have significant implications for our understanding of high redshift galaxies and galaxy evolution., Accepted to ApJ Letters
Published: 2013

17. Regional variations in the dense gas heating and cooling in M51 from Herschel far-infrared spectroscopy

Author: Suzanne C. Madden, Maarten Baes, Marc Sauvage, A. Cooray, K. Foyle, M. R. P. Schirm, T. J. Parkin, Alessandro Boselli, D. Cormier, Helene Roussel, I. De Looze, O. Ł. Karczewski, Médéric Boquien, Christine D. Wilson, L. Spinoglio, Vianney Lebouteiller, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Hydrogen density, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Photon, FOS: Physical sciences, Flux, Astrophysics, PHOTODISSOCIATION REGIONS, 01 natural sciences, 0103 physical sciences, Spectroscopy, 010303 astronomy & astrophysics, Physics, INTERSTELLAR-MEDIUM, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Molecular cloud, Astronomy and Astrophysics, Gas heating, Astrophysics - Astrophysics of Galaxies, Galaxy, Physics and Astronomy, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Far infrared spectroscopy, MOLECULAR CLOUDS, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present Herschel PACS and SPIRE spectroscopy of the most important far-infrared cooling lines in M51, [CII](158 \mu m), [NII](122 & 205 \mu m), [OI](63 and 145 \mu m) and [OIII](88 \mu m). We compare the observed flux of these lines with the predicted flux from a photon dominated region model to determine characteristics of the cold gas such as density, temperature and the far-ultraviolet radiation field, G_0, resolving details on physical scales of roughly 600 pc. We find an average [CII]/F_TIR of 4 x 10^{-3}, in agreement with previous studies of other galaxies. A pixel-by-pixel analysis of four distinct regions of M51 shows a radially decreasing trend in both the far-ultraviolet (FUV) radiation field, G_0 and the hydrogen density, n, peaking in the nucleus of the galaxy, then falling off out to the arm and interarm regions. We see for the first time that the FUV flux and gas density are similar in the differing environments of the arm and interarm regions, suggesting that the inherent physical properties of the molecular clouds in both regions are essentially the same., Comment: 24 pages, 7 figures, 9 tables; accepted for publication in the Astrophysical Journal
Published: 2013

18. The CO-to-H2 Conversion Factor and Dust-to-gas Ratio on Kiloparsec Scales in Nearby Galaxies

Author: L. Vigroux, Helene Roussel, Karl D. Gordon, G. Aniano, Jin Koda, Adam K. Leroy, P. N. Appleton, Kevin V. Croxall, Karin Sandstrom, J. Hinz, Sharon E. Meidt, Elias Brinks, Eva Schinnerer, E. Montiel, Maud Galametz, T. P. R. van der Laan, Kathryn Kreckel, Leslie K. Hunt, Charles W. Engelbracht, Robert C. Kennicutt, Ramin A. Skibba, Daniela Calzetti, Frederick M. Walter, Hans-Walter Rix, Anika Schmiedeke, Eric W. Pellegrini, Daniel A. Dale, Lee Armus, Antonio Usero, Brent Groves, J. Donovan Meyer, Mark G. Wolfire, Alberto D. Bolatto, Christine D. Wilson, Andreas Schruba, J. D. T. Smith, Bruce T. Draine, Alison F. Crocker, Hendrik Linz, Frank Bigiel, K. F. Schuster, W. J. G. de Blok, Oliver Krause, Marc Sauvage, and Bernhard R. Brandl
Subjects: Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Metallicity, Milky Way, FOS: Physical sciences, Astronomy and Astrophysics, Scale (descriptive set theory), Radius, Astrophysics, Alpha (navigation), Astrophysics - Astrophysics of Galaxies, Standard deviation, Galaxy, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Line (formation), Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present kiloparsec (kpc) spatial resolution maps of the CO-to-H2 conversion factor (alpha_co) and dust-to-gas ratio (DGR) in 26 nearby, star-forming galaxies. We have simultaneously solved for alpha_co and DGR by assuming that the DGR is approximately constant on kpc scales. With this assumption, we can combine maps of dust mass surface density, CO integrated intensity and HI column density to solve for both alpha_co and DGR with no assumptions about their value or dependence on metallicity or other parameters. Such a study has just become possible with the availability of high resolution far-IR maps from the Herschel key program KINGFISH, 12CO J=(2-1) maps from the IRAM 30m large program HERACLES and HI 21-cm line maps from THINGS. We use a fixed ratio between the (2-1) and (1-0) lines to present our alpha_co results on the more typically used 12CO J=(1-0) scale and show using literature measurements that variations in the line ratio do not effect our results. In total, we derive 782 individual solutions for alpha_co and DGR. On average, alpha_co = 3.1 Msun pc^-2 (K km s^-1)^-1 for our sample with a standard deviation of 0.3 dex. Within galaxies we observe a generally flat profile of alpha_co as a function of galactocentric radius. However, most galaxies exhibit a lower alpha_co in the central kpc---a factor of ~2 below the galaxy mean, on average. In some cases, the central alpha_co value can be factors of 5 to 10 below the standard Milky Way (MW) value of alpha_co,MW =4.4 Msun pc^-2 (K km s^-1)^-1. While for alpha_co we find only weak correlations with metallicity, DGR is well-correlated with metallicity, with an approximately linear slope. Finally, we present several recommendations for choosing an appropriate alpha_co for studies of nearby galaxies., Comment: accepted to ApJ July 9, 2013, 63 pages, 2-column ApJ format, p38-63 are an image atlas
Published: 2013

19. Modeling Dust and Starlight in Galaxies Observed by Spitzer and Herschel: NGC 628 and NGC 6946

Author: Leslie K. Hunt, Charles W. Engelbracht, Maud Galametz, Alberto D. Bolatto, J. Donovan Meyer, J. Hinz, Karl D. Gordon, Oliver Krause, Marc Sauvage, Jin Koda, Bruce T. Draine, Mark G. Wolfire, J. D. T. Smith, Helene Roussel, G. Aniano, George Helou, Lee Armus, H-W. Rix, Alison F. Crocker, Daniel A. Dale, Benjamin D. Johnson, Adam K. Leroy, Robert C. Kennicutt, Eric J. Murphy, Ramin A. Skibba, Daniela Calzetti, Karin Sandstrom, E. Montiel, and Fabian Walter
Subjects: Luminous infrared galaxy, Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Spiral galaxy, Metallicity, Extinction (astronomy), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, Luminosity, Photometry (optics), Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Cosmic dust, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We characterize the dust in NGC628 and NGC6946, two nearby spiral galaxies in the KINGFISH sample. With data from 3.6um to 500um, dust models are strongly constrained. Using the Draine & Li (2007) dust model, (amorphous silicate and carbonaceous grains), for each pixel in each galaxy we estimate (1) dust mass surface density, (2) dust mass fraction contributed by polycyclic aromatic hydrocarbons (PAH)s, (3) distribution of starlight intensities heating the dust, (4) total infrared (IR) luminosity emitted by the dust, and (5) IR luminosity originating in regions with high starlight intensity. We obtain maps for the dust properties, which trace the spiral structure of the galaxies. The dust models successfully reproduce the observed global and resolved spectral energy distributions (SEDs). The overall dust/H mass ratio is estimated to be 0.0082+/-0.0017 for NGC628, and 0.0063+/-0.0009 for NGC6946, consistent with what is expected for galaxies of near-solar metallicity. Our derived dust masses are larger (by up to a factor 3) than estimates based on single-temperature modified blackbody fits. We show that the SED fits are significantly improved if the starlight intensity distribution includes a (single intensity) "delta function" component. We find no evidence for significant masses of cold dust T, To be published in Apj, September 2012. See the full version at http://www.astro.princeton.edu/~ganiano/Papers/
Published: 2012

20. The Pipe Nebula as seen with Herschel: formation of filamentary structures by large-scale compression?

Author: Nicolas Peretto, J. P. Bernard, Leonardo Testi, Helene Roussel, T. Sousbie, P. Palmeirim, J. Di Francesco, Doris Arzoumanian, M. Attard, Annie Zavagno, Davide Elia, Glenn J. White, Ph. André, P. Didelon, Frédérique Motte, Derek Ward-Thompson, Martin Hennemann, Alexander Men'shchikov, T. Hill, Vera Könyves, Nicola Schneider, Jason M. Kirk, Q. Nguyen Luong, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), FORMATION STELLAIRE 2012, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), School of Physics and Astronomy [Cardiff], Cardiff University, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Engineering Department, University of Cambridge [UK] (CAM), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy, École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Physics, Gravity (chemistry), Nebula, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Star formation, Interstellar cloud, Flow (psychology), FOS: Physical sciences, Astronomy and Astrophysics, Scale (descriptive set theory), Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Compression (geology), 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, QB
Abstract: A growing body of evidence indicates that the formation of filaments in interstellar clouds is a key component of the star formation process. In this paper, we present new Herschel PACS and SPIRE observations of the B59 and Stem regions in the Pipe Nebula complex, revealing a rich, organized network of filaments. The asymmetric column density profiles observed for several filaments, along with the bow-like edge of B59, indicates that the Pipe Nebula is being compressed from its western side, most likely by the winds from the nearby Sco OB2 association. We suggest that this compressive flow has contributed to the formation of some of the observed filamentary structures. In B59, the only region of the entire Pipe complex showing star formation activity, the same compressive flow has likely enhanced the initial column density of the clump, allowing it to become globally gravitationally unstable. Although more speculative, we propose that gravity has also been responsible for shaping the converging filamentary pattern observed in B59. While the question of the relative impact of large-scale compression and gravity remains open in B59, large-scale compression appears to be a plausible mechanism for the initial formation of filamentary structures in the rest of the complex, Comment: 9 pages, 9 figures, accepted for publication in A&A
Published: 2012

21. The Dust Properties of Bubble HII Regions as seen by Herschel

Author: Martin Hennemann, L. Deharveng, Sylvain Bontemps, Helene Roussel, A. Abergel, D. Russeil, J. A. Rodón, J. P. Bernard, Ph. André, T. Hill, Annie Zavagno, Frédérique Motte, L. D. Anderson, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, FORMATION STELLAIRE 2012, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), and Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB)
Subjects: Infrared, Bubble, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Solar mass, SIMPLE (dark matter experiment), Line-of-sight, 010308 nuclear & particles physics, Star formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, Wavelength, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, Noise (radio), Galaxy Astrophysics
Abstract: Because of their relatively simple morphology, "bubble" HII regions have been instrumental to our understanding of star formation triggered by HII regions. With the far-infrared (FIR) spectral coverage of the Herschel satellite, we can access the wavelengths where these regions emit the majority of their energy through their dust emission. At Herschel wavelengths 70 micron to 500 micron, the emission associated with HII regions is dominated by the cool dust in their photodissociation regions (PDRs). We find average dust temperatures of 26K along the PDRs, with little variation between the HII regions in the sample, while local filaments and infrared dark clouds average 19K and 15K respectively. Higher temperatures lead to higher values of the Jeans mass, which may affect future star formation. The mass of the material in the PDR, collected through the expansion of the HII region, is between ~300 and ~10,000 Solar masses for the HII regions studied here. These masses are in rough agreement with the expected masses swept up during the expansion of the \hii\ regions. Approximately 20% of the total FIR emission is from the direction of the bubble central regions. This suggests that we are detecting emission from the "near-side" and "far-side" PDRs along the line of sight and that bubbles are three-dimensional structures. We find only weak support for a relationship between dust temperature and beta, of a form similar to that caused by noise and calibration uncertainties alone., Comment: Accepted by A&A. Figure sizes reduced for this version
Published: 2012

22. Interstellar matter and star formation in W5-E - A Herschel view

Author: Alain Abergel, Sylvain Bontemps, Helene Roussel, Ph. André, D. Russeil, G. Leleu, L. Deharveng, Frédérique Motte, Annie Zavagno, L. D. Anderson, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), FORMATION STELLAIRE 2012, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Solar mass, 010308 nuclear & particles physics, Star formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Interstellar medium, Protein filament, Stars, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Ionization, 0103 physical sciences, Black-body radiation, 010303 astronomy & astrophysics, Envelope (waves)
Abstract: W5-E has been observed with the Herschel-PACS and -SPIRE photometers, at 100, 160, 250, 350, and 500 microns. The dust temperature map shows a rather uniform temperature, in the range 17.5-20 K in the dense condensations or filaments, 21-22 K in the photodissociation regions, and 24-31 K in the direction of the ionized regions. The column densities are rather low, everywhere lower than 10^23 cm-2, and of the order of a few 10^21 cm-2 in the PDRs. About 8000 solar masses of neutral material surrounds the ionized region, which is low with respect to the volume of this HII region; we suggest that the exciting stars of the W5-E, W5-W, Sh~201, A and B HII regions formed along a dense filament or sheet rather than inside a more spherical cloud. Fifty point sources have been detected at 100 microns. Most of them are Class 0/I YSOs. The SEDs of their envelopes have been fitted using a modified blackbody model. These envelopes are cold, with a mean temperature of 15.7+-1.8K. Their masses are in the range 1.3-47 solar masses. Eleven of these point sources are candidate Class 0 YSOs. Twelve of these point sources are possibly at the origin of bipolar outflows detected in this region. None of the YSOs contain a massive central object, but a few may form a massive star as they have both a massive envelope and also a high envelope accretion rate. Most of the Class 0/I YSOs are observed in the direction of high column density material, for example in the direction of the massive condensations present at the waist of the bipolar Sh 201 HII region or enclosed by the bright-rimmed cloud BRC14. The overdensity of Class 0/I YSOs on the borders of the HII regions strongly suggests that triggered star formation is at work in this region but, due to insufficient resolution, the exact processes at the origin of the triggering are difficult to determine., Comment: 41 pages, 36 figures, accepted by A&A
Published: 2012

23. A study of heating and cooling of the ISM in NGC 1097 with Herschel-pacs and Spitzer-IRS

Author: L. Vigroux, Robert C. Kennicutt, George Helou, H.-W. Rix, Helene Roussel, Jennifer Donovan Meyer, Adam K. Leroy, Eric J. Murphy, Yiming Li, Jin Koda, P. Beirao, Eva Schinnerer, Daniela Calzetti, Kevin V. Croxall, Gaelle Dumas, P. N. Appleton, Cai-Na Hao, Joannah L. Hinz, Fabian Walter, Mark G. Wolfire, Alberto D. Bolatto, Sundar Srinivasan, Lee Armus, Bruce T. Draine, J. D. T. Smith, Daniel A. Dale, Nurur Rahman, Oliver Krause, B. E. Warren, Benjamin D. Johnson, Alison F. Crocker, T. P. R. van der Laan, Marc Sauvage, Bernhard R. Brandl, Maud Galametz, Karin Sandstrom, Sharon E. Meidt, Brent Groves, G. Aniano, A. Gil de Paz, and Karl D. Gordon
Subjects: Astrofísica, C-II, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Infrared, FOS: Physical sciences, STAR-FORMING, Astrophysics, PHOTODISSOCIATION REGIONS, Ring (chemistry), galaxies [infrared], SEYFERT-GALAXIES, individual (NGC 1097) [galaxies], Far infrared, Ionization, Emission spectrum, Physics, INTERSTELLAR-MEDIUM, ISM [galaxies], starburst [galaxies], Photodissociation, Astronomy and Astrophysics, IRON PROJECT, TRANSLUCENT CLOUDS, Astrophysics - Astrophysics of Galaxies, Galaxy, GALAXIES, Astronomía, Physics and Astronomy, Space and Planetary Science, MOLECULAR-HYDROGEN, Astrophysics of Galaxies (astro-ph.GA), FAR-INFRARED SPECTROSCOPY, NEARBY GALAXIES SURVEY, Astrophysics - Cosmology and Nongalactic Astrophysics, Bar (unit)
Abstract: NGC 1097 is a nearby Seyfert 1 galaxy with a bright circumnuclear starburst ring, a strong large-scale bar and an active nucleus. We present a detailed study of the spatial variation of the far infrared (FIR) [CII]158um and [OI]63um lines and mid-infrared H2 emission lines as tracers of gas cooling, and of the polycyclic aromatic hydrocarbon (PAH) bands as tracers of the photoelectric heating, using Herschel-PACS, and Spitzer-IRS infrared spectral maps. We focus on the nucleus and the ring, and two star forming regions (Enuc N and Enuc S). We estimated a photoelectric gas heating efficiency ([CII]158um+[OI]63um)/PAH in the ring about 50% lower than in Enuc N and S. The average 11.3/7.7um PAH ratio is also lower in the ring, which may suggest a larger fraction of ionized PAHs, but no clear correlation with [CII]158{\mu}m/PAH(5.5 - 14um) is found. PAHs in the ring are responsible for a factor of two more [CII]158um and [OI]63um emission per unit mass than PAHs in the Enuc S. SED modeling indicates that at most 25% of the FIR power in the ring and Enuc S can come from high intensity photodissociation regions (PDRs), in which case G0 ~ 10^2.3 and nH ~ 10^3.5 cm^-3 in the ring. For these values of G0 and nH PDR models cannot reproduce the observed H2 emission. Much of the the H2 emission in the starburst ring could come from warm regions in the diffuse ISM that are heated by turbulent dissipation or shocks., Comment: 17 pages, 14 figures, 5 tables; accepted for publication in ApJ
Published: 2012

24. The M16 molecular complex under the influence of NGC6611. Herschel's perspective of the heating effect on the Eagle Nebula

Author: J. P. Bernard, D. Polychroni, Stefano Pezzuto, Michael J. Griffin, Q. Nguyen Luong, E. Schisano, T. Hill, Vincent Minier, A. P. Marston, Nicola Schneider, Kazi L.J. Rygl, Helene Roussel, P. Didelon, Sylvain Bontemps, Marc Sauvage, T. Sousbie, Annie Zavagno, J. Di Francesco, Frédérique Motte, Glenn J. White, Ph. André, Davide Elia, L. D. Anderson, Martin Hennemann, Nicolas Peretto, Leonardo Testi, D. Ward Thompson, J. Z. Li, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Engineering Department, University of Cambridge [UK] (CAM), FORMATION STELLAIRE 2012, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), National Astronomical Observatories [Beijing] (NAOC), Chinese Academy of Sciences [Beijing] (CAS), Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Consiglio Nazionale delle Ricerche (CNR), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Physics, Nebula, 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], FOS: Physical sciences, Spectral density, Astronomy and Astrophysics, Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Protein filament, Temperature gradient, Star cluster, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Cluster (physics), Protostar, Pillars of Creation, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), QB
Abstract: We present Herschel images from the HOBYS key program of the Eagle Nebula (M16) in the far-infrared and sub-millimetre, using the PACS and SPIRE cameras at 70{\mu}m, 160{\mu}m, 250{\mu}m, 350{\mu}m, 500{\mu}m. M16, home to the Pillars of Creation, is largely under the influence of the nearby NGC6611 high-mass star cluster. The Herschel images reveal a clear dust temperature gradient running away from the centre of the cavity carved by the OB cluster. We investigate the heating effect of NGC6611 on the entire M16 star-forming complex seen by Herschel including the diffuse cloud environment and the dense filamentary structures identified in this region. In addition, we interpret the three-dimensional geometry of M16 with respect to the nebula, its surrounding environment, and the NGC6611 cavity. The dust temperature and column density maps reveal a prominent eastern filament running north-south and away from the high-mass star-forming central region and the NGC6611 cluster, as well as a northern filament which extends around and away from the cluster. The dust temperature in each of these filaments decreases with increasing distance from the NGC6611 cluster, indicating a heating penetration depth of \sim 10 pc in each direction in 3 - 6 \times 10^{22} cm-2 column density filaments. We show that in high-mass star-forming regions OB clusters impact the temperature of future star-forming sites, modifying the initial conditions for collapse and effecting the evolutionary criteria of protostars developed from spectral energy distributions. Possible scenarios for the origin of the morphology seen in this region are discussed, including a western equivalent to the eastern filament, which was destroyed by the creation of the OB cluster and its subsequent winds and radiation., Comment: 12 pages, including 3 appendix, 9 figures, accepted by A&A
Published: 2012

25. The Herschel view of massive star formation in G035.39--00.33: a dense and cold filament of W48 undergoing a mini-starburst

Author: Peter G. Martin, Glenn J. White, Doris Arzoumanian, Anaëlle Maury, Ph. André, Martin Hennemann, M. R. Pestalozzi, Nicolas Peretto, T. Hill, Leonardo Testi, Nicola Schneider, Stefano Pezzuto, Jason M. Kirk, Marc Sauvage, L. Deharveng, Derek Ward-Thompson, P. Didelon, Vincent Minier, Matthew Joseph Griffin, Helene Roussel, Kazi L.J. Rygl, Sergio Molinari, J. Di Francesco, Sylvain Bontemps, Frederic Schuller, Q. Nguyen Luong, Michael A. Reid, Vera Könyves, Alexander Men'shchikov, L. D. Anderson, Annie Zavagno, Frédérique Motte, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Observatoire Astronomique de Marseille Provence (OAMP), Université de Provence - Aix-Marseille 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), Laboratoire de Modélisation Multi-échelles des Combustibles (LM2C), Service d'Etudes de Simulation du Comportement du combustibles (SESC), Département d'Etudes des Combustibles (DEC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Département d'Etudes des Combustibles (DEC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Southern Observatory (ESO), Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), CTVR/Stokes Institute, Engineering Research Building, University of Limerick (UL), Laboratoire des matériaux et du génie physique (LMGP ), Institut National Polytechnique de Grenoble (INPG)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Radioastronomie (MPIFR), School of Physics and Astronomy [Cardiff], Cardiff University, Engineering Department, University of Cambridge [UK] (CAM), CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction de l'Energie Nucléaire (CEA-DEN), Laboratoire des matériaux et du génie physique (LMGP), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Institut d'Astrophysique de Paris (IAP), and Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, 010308 nuclear & particles physics, Infrared, Star formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Molecular cloud, Spectral density, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Ridge (differential geometry), [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], 01 natural sciences, Protein filament, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, 0103 physical sciences, Protostar, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), QB
Abstract: The filament IRDC G035.39--00.33 in the W48 molecular complex is one of the darkest infrared clouds observed by \textit{Spitzer}. It has been observed by the PACS (70 and 160\,$\micron$) and SPIRE (250, 350, and 500\,$\micron$) cameras of the \textit{Herschel} Space Observatory as part of the W48 molecular cloud complex in the framework of the HOBYS key programme. The observations reveal a sample of 28 compact sources (deconvolved FWHM sizes $$$20 \msun$. The cloud characteristics we derive from the analysis of their spectral energy distributions are masses of $20-50 \msun$, sizes of 0.1--0.2 pc, and average densities of $2-20 \times 10^{5} \cmc$, which make these massive dense cores excellent candidates to form intermediate- to high-mass stars. Most of the massive dense cores are located inside the G035.39--00.33 ridge and host IR-quiet high-mass protostars. The large number of protostars found in this filament suggests that we are witnessing a mini-burst of star formation with an efficiency of $\sim$15% and a rate density of $\sim$$40 \msun\,$yr$^{-1}\,$kpc$^{-2}$ within $\sim$8 pc$^2$, a large area covering the full ridge. Part of the extended SiO emission observed towards G035.39--00.33 is not associated with obvious protostars and may originate from low-velocity shocks within converging flows, as advocated by previous studies., Comment: accepted to publish in A&A 16 Sep 2011,11 pages, 11 figures
Published: 2011

26. The Herschel Exploitation of Local Galaxy Andromeda (HELGA). I: Global far-infrared and sub-mm morphology

Author: A. Remy, M. J. Page, Stephen Anthony Eales, Jacopo Fritz, Walter Kieran Gear, I. De Looze, Haley Louise Gomez, B. O'Halloran, Alessandro Boselli, Karl D. Gordon, George J. Bendo, C. D. Wilson, Vianney Lebouteiller, Frédéric Galliano, Joris Verstappen, C. Waelkens, A. Cooray, Gianfranco Gentile, Mattia Vaccari, Joris Blommaert, S. C. Madden, Helene Roussel, David L. Clements, Luca Cortese, Maarten Baes, Matthew Smith, L. Spinoglio, David A. Thilker, Robert Braun, Médéric Boquien, G. P. Ford, Jason M. Kirk, J. Roman Duval, Laboratoire de Biophotonique et Pharmacologie - UMR 7213 (LBP), Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS), AUTRES, Technische Universität Dresden = Dresden University of Technology (TU Dresden), Universiteit Gent = Ghent University (UGENT), Sterrenkundig Observatorium, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), School of Physics and Astronomy [Cardiff], Cardiff University, Department of Chemistry and Biochemistry, University of California [Los Angeles] (UCLA), University of California (UC)-University of California (UC), aucun, Macif, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Antarctic Research a European Network for Astrophysics (ARENA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Department of Physics and Astronomy [Baltimore], Johns Hopkins University (JHU), Dipartimento di Astronomia [Padova], Università degli Studi di Padova = University of Padua (Unipd), Department of Physics and Astronomy [South Africa], University of the Western Cape (UWC), McMaster University [Hamilton, Ontario], Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Technische Universität Dresden (TUD), Universiteit Gent [Ghent], Universiteit Gent, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), School of Physics and Astronomy, University of California-University of California, Dipartimento di Astronomia, Universita degli Studi di Padova, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)), Universiteit Gent = Ghent University [Belgium] (UGENT), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), and University of the Western Cape
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), 010504 meteorology & atmospheric sciences, Metallicity, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, SPIRE INSTRUMENT, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, CONVERSION FACTOR, EXTENDED SURVEY HERM33ES, 01 natural sciences, STAR-FORMATION, Far infrared, 0103 physical sciences, 010303 astronomy & astrophysics, individual: M31 [galaxies], Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, QB, Physics, Spiral galaxy, ISM [galaxies], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Star formation, MESSIER 31, M31, ISM [infrared], Astronomy and Astrophysics, Galaxy, ATOMIC GAS, Andromeda, BACKGROUND EXPERIMENT, Physics and Astronomy, Space and Planetary Science, Cirrus, LARGE-MAGELLANIC-CLOUD, Astrophysics::Earth and Planetary Astrophysics, INTERSTELLAR DUST, Data reduction, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We have obtained Herschel images at five wavelengths from 100 to 500 micron of a ~5.5x2.5 degree area centred on the local galaxy M31 (Andromeda), our nearest neighbour spiral galaxy, as part of the Herschel guaranteed time project "HELGA". The main goals of HELGA are to study the characteristics of the extended dust emission, focusing on larger scales than studied in previous observations of Andromeda at an increased spatial resolution, and the obscured star formation. In this paper we present data reduction and Herschel maps, and provide a description of the far-infrared morphology, comparing it with features seen at other wavelengths. We use high--resolution maps of the atomic hydrogen, fully covering our fields, to identify dust emission features that can be associated to M31 with confidence, distinguishing them from emission coming from the foreground Galactic cirrus. Thanks to the very large extension of our maps we detect, for the first time at far-infrared wavelengths, three arc-like structures extending out to ~21, ~26 and ~31 kpc respectively, in the south-western part of M31. The presence of these features, hosting ~2.2e6 Msol of dust, is safely confirmed by their detection in HI maps. Overall, we estimate a total dust mass of ~5.8e7 Msol, about 78% of which is contained in the two main ring-like structures at 10 and 15 kpc, at an average temperature of 16.5 K. We find that the gas-to-dust ratio declines exponentially as a function of the galacto-centric distance, in agreement with the known metallicity gradient, with values ranging from 66 in the nucleus to ~275 in the outermost region. [Abridged], Comment: 15 Pages, 9 Figures. Accepted for publication in Astronomy and Astrophysics. A high resolution version of the paper can be found at http://wazn.ugent.be/jfritz/HelgaI_final.pdf
Published: 2011
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27. FIR colours and SEDs of nearby galaxies observed with Herschel

Author: Stefano Zibetti, Matthew Joseph Griffin, Diane Cormier, Werner W. Zeilinger, Maud Galametz, L. Spinoglio, E. E. Rigby, Thomas M. Hughes, Andreas Papageorgiou, Aliakbar Dariush, Simone Bianchi, Jonathan Ivor Davies, Dario Fadda, Michael Pohlen, Anthony P. Jones, Marc Sauvage, Leslie K. Hunt, N. Lu, N. Castro-Rodriguez, Daniele Pierini, Gillian S. Wright, Jamie Stevens, Sacha Hony, Laure Ciesla, Herve Wozniak, Eli Dwek, Pierre Chanial, Jacopo Fritz, Kate Gudrun Isaak, Asantha Cooray, Ismael Perez-Fournon, L. Vigroux, Maximilien R. P. Schirm, Jason Glenn, Matthew Smith, D. J. Bomans, George J. Bendo, Alessandro Boselli, Marco Grossi, D. A. Garcia-Appadoo, Mattia Vaccari, M. Bradford, A. Rykala, Suzanne C. Madden, V. Buat, Koryo Okumura, Catherine Vlahakis, S. Sabatini, Christine D. Wilson, B. O'Halloran, Edvige Corbelli, James J. Bock, Frédéric Galliano, L. R. Levenson, Giuseppe Gavazzi, Markos Trichas, Helene Roussel, David L. Clements, Luca Cortese, Marcel Clemens, Benjamin L. Schulz, Seb Oliver, Stephane Charlot, Carlo Giovanardi, Maarten Baes, Emmanuel M. Xilouris, Joris Verstappen, Naseem Rangwala, Stephen Anthony Eales, N. Sacchi, P. Panuzzo, Robbie Richard Auld, T. J. Parkin, S. Sundar, M. J. Page, David Elbaz, M. Symeonidis, S. di Serego Alighieri, Haley Louise Gomez, Walter Kieran Gear, I. De Looze, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Science and Technology Facilities Council (STFC), Boselli, A, Ciesla, L, Buat, V, Cortese, L, Auld, R, Baes, M, Bendo, G, Bianchi, S, Bock, J, Bomans, D, Bradford, M, Castro Rodriguez, N, Chanial, P, Charlot, S, Clemens, M, Clements, D, Corbelli, E, Cooray, A, Cormier, D, Dariush, A, Davies, J, De Looze, I, di Serego Alighieri, S, Dwek, E, Eales, S, Elbaz, D, Fadda, D, Fritz, J, Galametz, M, Galliano, F, Garcia Appadoo, D, Gavazzi, G, Gear, W, Giovanardi, C, Glenn, J, Gomez, H, Griffin, M, Grossi, M, Hony, S, Hughes, T, Hunt, L, Isaak, K, Jones, A, Levenson, L, Lu, N, Madden, S, O'Halloran, B, Okumura, K, Oliver, S, Page, M, Panuzzo, P, Papageorgiou, A, Parkin, T, Perez Fournon, I, Pierini, D, Pohlen, M, Rangwala, N, Rigby, E, Roussel, H, Rykala, A, Sabatini, S, Sacchi, N, Sauvage, M, Schulz, B, Schirm, M, Smith, M, Spinoglio, L, Stevens, J, Sundar, S, Symeonidis, M, Trichas, M, Vaccari, M, Verstappen, J, Vigroux, L, Vlahakis, C, Wilson, C, Wozniak, H, Wright, G, Xilouris, E, Zeilinger, W, and Zibetti, S
Subjects: Infrared, Radio galaxy, DUST, Astrophysics, 01 natural sciences, galaxies [infrared], Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, QB, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], ATLAS, VIRGO CLUSTER, spiral [galaxies], Physical Sciences, astro-ph.CO, Astrophysics::Earth and Planetary Astrophysics, galaxies: ISM, Astrophysics - Cosmology and Nongalactic Astrophysics, galaxies: spiral, Active galactic nucleus, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Metallicity, INFRARED-EMISSION, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astronomy & Astrophysics, Color temperature, infrared: galaxies, cD, FIS/05 - ASTRONOMIA E ASTROFISICA, 0103 physical sciences, Emissivity, STAR-FORMING GALAXIES, DISTRIBUTIONS, Astrophysics::Galaxy Astrophysics, Science & Technology, ISM [galaxies], 010308 nuclear & particles physics, Star formation, Astronomy and Astrophysics, Galaxy, UV, 0201 Astronomical And Space Sciences, SPITZER, SPECTRAL ENERGY-DISTRIBUTION, Physics and Astronomy, 13. Climate action, Space and Planetary Science, galaxies: elliptical and lenticular, cD, elliptical and lenticular [galaxies]
Abstract: We present infrared colours (in the 25-500 mic spectral range) and UV to radio continuum spectral energy distributions of a sample of 51 nearby galaxies observed with SPIRE on Herschel. The observed sample includes all morphological classes, from quiescent ellipticals to active starbursts. Active galaxies have warmer colour temperatures than normal spirals. In ellipticals hosting a radio galaxy, the far-infrared (FIR) emission is dominated bynthe synchrotron nuclear emission. The colour temperature of the cold dust is higher in quiescent E-S0a than in star-forming systems probably because of the different nature of their dust heating sources (evolved stellar populations, X-ray, fast electrons) and dust grain properties. In contrast to the colour temperature of the warm dust, the f350/f500 index sensitive to the cold dust decreases with star formation and increases with metallicity, suggesting an overabundance of cold dust or an emissivity parameter beta, Accepted for publication on A&A, Herschel special issue
Published: 2010

28. Far-infrared line imaging of the starburst ring in NGC 1097 with the Herschel/PACS spectrometer

Author: Ramin A. Skibba, Alberto D. Bolatto, Daniela Calzetti, Lee Armus, P. N. Appleton, Karl D. Gordon, Brent Groves, Daniel A. Dale, B. E. Warren, George Helou, N. Rahman, Fabian Walter, Helene Roussel, Joannah L. Hinz, Benjamin D. Johnson, Marc Sauvage, Jin Koda, A. Gil de Paz, Bruce T. Draine, John Richer, Bernhard R. Brandl, Sharon E. Meidt, C. D. Wilson, Kevin V. Croxall, Karin Sandstrom, Mark G. Wolfire, Sundar Srinivasan, Gaelle Dumas, Cai-Na Hao, H-W. Rix, P. Beirao, Leslie K. Hunt, Charles W. Engelbracht, Adam K. Leroy, Robert C. Kennicutt, Eric J. Murphy, Eva Schinnerer, Oliver Krause, Stefano Zibetti, J. D. T. Smith, and Alison F. Crocker
Subjects: Astrofísica, Cosmology and Nongalactic Astrophysics (astro-ph.CO), ACTIVE GALAXIES, FOS: Physical sciences, Astrophysics, NUCLEAR, DIAGNOSTICS, Ring (chemistry), SPIRAL GALAXY NGC-1097, galaxies [infrared], individual: NGC 1097 [galaxies], photon-dominated region, Spitzer Space Telescope, Far infrared, Seyfert [galaxies], Emission spectrum, Line (formation), Physics, SPECTROSCOPY, Spectrometer, starburst [galaxies], Astronomy and Astrophysics, CIRCUMNUCLEAR STAR-FORMATION, REGIONS, imaging spectroscopy [techniques], Galaxy, Interstellar medium, Astronomía, Physics and Astronomy, Space and Planetary Science, GAS, EMISSION, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: NGC 1097 is a nearby SBb galaxy with a Seyfert nucleus and a bright starburst ring. We study the physical properties of the interstellar medium (ISM) in the ring using spatially resolved far-infrared spectral maps of the circumnuclear starburst ring of NGC 1097, obtained with the PACS spectrometer on board the Herschel Space Telescope. In particular, we map the important ISM cooling and diagnostic emission lines of [OI] 63 $\mu$m, [OIII] 88 $\mu$m, [NII] 122 $\mu$m, [CII] 158 $\mu$m and [NII] 205 $\mu$m. We observe that in the [OI] 63 $\mu$m, [OIII] 88 $\mu$m, and [NII] 122 $\mu$m line maps, the emission is enhanced in clumps along the NE part of the ring. We observe evidence of rapid rotation in the circumnuclear ring, with a rotation velocity of ~220$ km s$^{-1}$ (inclination uncorrected) measured in all lines. The [OI] 63 $\mu$m/[CII] 158 $\mu$m ratio varies smoothly throughout the central region, and is enhanced on the northeastern part of the ring, which may indicate a stronger radiation field. This enhancement coincides with peaks in the [OI] 63 $\mu$m and [OIII] 88 $\mu$m maps. Variations of the [NII] 122 $\mu$m/[NII] 205 $\mu$m ratio correspond to a range in the ionized gas density between 150 and 400 cm$^{-3}$., Comment: Accepted for publication on the A&A Herschel Special Issue
Published: 2010

29. In-flight calibration of the Herschel-SPIRE instrument

Author: L. Zhang, Hien Nguyen, A. Rykala, Helene Roussel, Douglas Griffin, S. Ronayette, James J. Bock, A. Conley, Edward Polehampton, Dominique Benielli, Bruce Sibthorpe, George J. Bendo, Dimitra Rigopoulou, H. Triou, Markos Trichas, L. R. Levenson, Arnold A. Schwartz, Bernhard Schulz, Darren Dowell, T. Fulton, Andreas Papageorgiou, B. M. Swinyard, K. J. King, Jean-Paul Baluteau, S. C. Jones, Ivan Valtchanov, P. Imhof, S. Guest, L. Conversi, David L. Shupe, Drew Brisbin, Matthew Joseph Griffin, Peter A. R. Ade, Gibion Makiwa, M. J. Barlow, Michael Pohlen, C. P. Pearson, D. Pouliquen, Locke D. Spencer, C. K. Xu, A. Dowell, Anthony J. Smith, Kate Gudrun Isaak, Roger Wesson, S. D. Sidher, Adrian M. Glauser, Adam Woodcraft, Jason Glenn, Seb Oliver, David A. Naylor, Pasquale Panuzzo, Giorgio Savini, Marc Ferlet, Herve Aussel, Michael Zemcov, Nanyao Y. Lu, T. L. Lim, S. J. Leeks, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Solar System, Fourier transform spectrometers, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, Spectral line, law.invention, 010309 optics, Telescope, law, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, [INFO]Computer Science [cs], space vehicles: instruments, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, instrumentation: spectrographs, Remote sensing, Physics, Data processing, Spectrometer, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Photometer, instrumentation: photometers, Wavelength, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: SPIRE, the Spectral and Photometric Imaging Receiver, is the Herschel Space Observatory's submillimetre camera and spectrometer. It contains a three-band imaging photometer operating at 250, 350 and 500 {\mu}m, and an imaging Fourier transform spectrometer (FTS) covering 194-671 {\mu}m (447-1550 GHz). In this paper we describe the initial approach taken to the absolute calibration of the SPIRE instrument using a combination of the emission from the Herschel telescope itself and the modelled continuum emission from solar system objects and other astronomical targets. We present the photometric, spectroscopic and spatial accuracy that is obtainable in data processed through the "standard" pipelines. The overall photometric accuracy at this stage of the mission is estimated as 15% for the photometer and between 15 and 50% for the spectrometer. However, there remain issues with the photometric accuracy of the spectra of low flux sources in the longest wavelength part of the SPIRE spectrometer band. The spectrometer wavelength accuracy is determined to be better than 1/10th of the line FWHM. The astrometric accuracy in SPIRE maps is found to be 2 arcsec when the latest calibration data are used. The photometric calibration of the SPIRE instrument is currently determined by a combination of uncertainties in the model spectra of the astronomical standards and the data processing methods employed for map and spectrum calibration. Improvements in processing techniques and a better understanding of the instrument performance will lead to the final calibration accuracy of SPIRE being determined only by uncertainties in the models of astronomical standards., Comment: Accepted for publication in Astronomy&Astrophysics, Herschel First Results special issue
Published: 2010
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30. The Herschel first look at protostars in the Aquila Rift

Author: Matthew Joseph Griffin, Adam Woodcraft, Marc Sauvage, Stefano Pezzuto, Vera Könyves, Bruce Sibthorpe, Frédérique Motte, Vincent Minier, Doris Arzoumanian, Pierre Cox, Peter Charles Hargrave, P. Didelon, Nicolas Peretto, Annie Zavagno, Alexander Men'shchikov, J.-Ph. Bernard, Glenn J. White, Ph. André, Leonardo Testi, Bruno Merín, J. Di Francesco, Göran Olofsson, C. D. Wilson, R. Vavrek, M. Attard, Alain Abergel, Sylvain Bontemps, Maohai Huang, A. M. Di Giorgo, J.-P. Baluteau, Timo Prusti, P. Saraceno, Nicola Schneider, Jason M. Kirk, Anaëlle Maury, Derek Ward-Thompson, Peter Martin, Jin-Zeng Li, Sergio Molinari, Helene Roussel, D. Russeil, L. Spinoglio, L. Cambrésy, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), European Southern Observatory (ESO), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), School of Physics and Astronomy [Cardiff], Cardiff University, National Astronomical Observatories [Beijing] (NAOC), Chinese Academy of Sciences [Beijing] (CAS), School of Physics and Astronomy, Photochimie moléculaire et macromoléculaire (PMM), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), CITA, University of Toronto, Stockholm University, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Royal Observatory Edinburgh (ROE), University of Edinburgh, Antarctic Research a European Network for Astrophysics (ARENA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), University of Exeter, Observatoire Astronomique de Marseille Provence (OAMP), Université de Provence - Aix-Marseille 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Rift, Serpens, 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Global statistics, Spire, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Protostar, 010303 astronomy & astrophysics, Dust emission
Abstract: As part of the science demonstration phase of the Herschel mission of the Gould Belt Key Program, the Aquila Rift molecular complex has been observed. The complete ~ 3.3deg x 3.3deg imaging with SPIRE 250/350/500 micron and PACS 70/160 micron allows a deep investigation of embedded protostellar phases, probing of the dust emission from warm inner regions at 70 and 160 micron to the bulk of the cold envelopes between 250 and 500 micron. We used a systematic detection technique operating simultaneously on all Herschel bands to build a sample of protostars. Spectral energy distributions are derived to measure luminosities and envelope masses, and to place the protostars in an M_env - L_bol evolutionary diagram. The spatial distribution of protostars indicates three star-forming sites in Aquila, with W40/Sh2-64 HII region by far the richest. Most of the detected protostars are newly discovered. For a reduced area around the Serpens South cluster, we could compare the Herschel census of protostars with Spitzer results. The Herschel protostars are younger than in Spitzer with 7 Class 0 YSOs newly revealed by Herschel. For the entire Aquila field, we find a total of ~ 45-60 Class 0 YSOs discovered by Herschel. This confirms the global statistics of several hundred Class~0 YSOs that should be found in the whole Gould Belt survey., Comment: 6 pages, 6 figures, publication in A&A
Published: 2010

31. Mapping the interstellar medium in galaxies with Herschel/SPIRE

Author: Werner W. Zeilinger, Jamie Stevens, L. Vigroux, Maud Galametz, Helene Roussel, David L. Clements, Jonathan Ivor Davies, Luca Cortese, Marc Sauvage, N. Lu, Walter Kieran Gear, B. O'Halloran, Matthew Joseph Griffin, Herve Wozniak, Eli Dwek, Diane Cormier, Ismael Perez-Fournon, M. J. Barlow, E. E. Rigby, Christine D. Wilson, Naseem Rangwala, Maximilien R. P. Schirm, Michael Pohlen, Andreas Papageorgiou, Alessandro Boselli, Mat Page, Sacha Hony, V. Buat, Jason Glenn, Pierre Chanial, Gillian S. Wright, Maarten Baes, L. R. Levenson, Haley Louise Gomez, N. Sacchi, George J. Bendo, Matthew Smith, Mattia Vaccari, Sundar Srinivasan, Benjamin L. Schulz, A. Cooray, M. Symeonidis, Kate Gudrun Isaak, James J. Bock, Pasquale Panuzzo, A. Rykala, Seb Oliver, Stephane Charlot, Robbie Richard Auld, T. J. Parkin, Stephen Anthony Eales, Laure Ciesla, Markos Trichas, Suzanne C. Madden, M. Bradford, Frédéric Galliano, Koryo Okumura, L. Spinoglio, N. Castro-Rodriguez, D. Elbaz, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire astronomique de Strasbourg (ObAS), and Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, galaxies: spiral, Cosmology and Nongalactic Astrophysics (astro-ph.CO), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], extinction, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, ISM: abundances, Interstellar medium, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics::Earth and Planetary Astrophysics, dust, Astrophysics::Galaxy Astrophysics, galaxies: ISM, QB, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The standard method of mapping the interstellar medium in a galaxy, by observing the molecular gas in the CO 1-0 line and the atomic gas in the 21-cm line, is largely limited with current telescopes to galaxies in the nearby universe. In this letter, we use SPIRE observations of the galaxies M99 and M100 to explore the alternative approach of mapping the interstellar medium using the continuum emission from the dust. We have compared the methods by measuring the relationship between the star-formation rate and the surface density of gas in the galaxies. We find the two methods give relationships with a similar dispersion, confirming that observing the continuum emission from the dust is a promising method of mapping the interstellar medium in galaxies., Astronomy and Astrophysics in press
Published: 2010

32. Herschel photometric observations of the nearby low metallicity irregular galaxy NGC 6822

Author: N. Sacchi, George J. Bendo, Mat Page, Ismael Perez-Fournon, Michael Pohlen, Alessandro Boselli, L. R. Levenson, Eli Dwek, Benjamin L. Schulz, B. O'Halloran, A. Cooray, Laure Ciesla, Maud Galametz, Pierre Chanial, M. J. Barlow, A. Rykala, Pasquale Panuzzo, Maximilien R. P. Schirm, Walter Kieran Gear, Naseem Rangwala, Jason Glenn, V. Buat, Jamie Stevens, Jonathan Ivor Davies, Marc Sauvage, Christine D. Wilson, Diane Cormier, Markos Trichas, N. Lu, Herve Wozniak, E. E. Rigby, Maarten Baes, Frédéric Galliano, Werner W. Zeilinger, Andreas Papageorgiou, Seb Oliver, Robbie Richard Auld, D. Elbaz, Matthew Smith, Haley Louise Gomez, James J. Bock, L. Spinoglio, Stephane Charlot, Kate Gudrun Isaak, Sacha Hony, Gillian S. Wright, Mattia Vaccari, T. J. Parkin, Stephen Anthony Eales, Matthew Joseph Griffin, N. Castro-Rodriguez, M. Symeonidis, M. Bradford, Koryo Okumura, S. Sundar, Suzanne C. Madden, Helene Roussel, David L. Clements, Luca Cortese, L. Vigroux, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire astronomique de Strasbourg (ObAS), and Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: GRAPHITE, Cosmology and Nongalactic Astrophysics (astro-ph.CO), dwarf [galaxies], Metallicity, INFRARED-EMISSION, Carbon dust, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, AMORPHOUS-CARBON, Emissivity, Astrophysics::Solar and Stellar Astrophysics, Surface brightness, education, Astrophysics::Galaxy Astrophysics, QB, Physics, education.field_of_study, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], ISM [galaxies], Star formation, Astronomy and Astrophysics, galaxies: dwarf, STAR-FORMATION HISTORY, Galaxy, galaxies: photometry, Spire, Physics and Astronomy, [SDU]Sciences of the Universe [physics], Space and Planetary Science, photometry [galaxies], Astrophysics::Earth and Planetary Astrophysics, Irregular galaxy, galaxies: ISM, INTERSTELLAR DUST, Astrophysics - Cosmology and Nongalactic Astrophysics, LOCAL GROUP, SPITZE
Abstract: We present the first Herschel PACS and SPIRE images of the low-metallicity galaxy NGC6822 observed from 70 to 500 mu and clearly resolve the HII regions with PACS and SPIRE. We find that the ratio 250/500 is dependent on the 24 mu surface brightness in NGC6822, which would locally link the heating processes of the coldest phases of dust in the ISM to the star formation activity. We model the SEDs of some regions HII regions and less active regions across the galaxy and find that the SEDs of HII regions show warmer ranges of dust temperatures. We derive very high dust masses when graphite is used in our model to describe carbon dust. Using amorphous carbon, instead, requires less dust mass to account for submm emission due to its lower emissivity properties. This indicates that SED models including Herschel constraints may require different dust properties than commonly used., Comment: Accepted for publication in the A&A Herschel first results Special Issue
Published: 2010
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33. Herschel-SPIRE observations of the disturbed galaxy NGC 4438

Author: Laure Ciesla, Pierre Chanial, James J. Bock, Stephane Charlot, B. O'Halloran, Michael Pohlen, Jonathan Ivor Davies, Naseem Rangwala, M. Bradford, Andreas Papageorgiou, V. Buat, Markos Trichas, Koryo Okumura, Maud Galametz, George J. Bendo, Marc Sauvage, N. Lu, Robbie Richard Auld, David Elbaz, M. Griffin, Mattia Vaccari, Walter Kieran Gear, L. R. Levenson, S. C. Madden, C. D. Wilson, Herve Wozniak, Pasquale Panuzzo, Werner W. Zeilinger, Helene Roussel, David L. Clements, N. Sacchi, Stephen Anthony Eales, Sundar Srinivasan, Diane Cormier, Jamie Stevens, Luca Cortese, N. Castro-Rodriguez, Kate Gudrun Isaak, Frédéric Galliano, E. E. Rigby, M. Symeonidis, Sacha Hony, Ismael Perez-Fournon, Gillian S. Wright, Maximilien R. P. Schirm, Alessandro Boselli, T. J. Parkin, Jason Glenn, M. J. Page, L. Spinoglio, Seb Oliver, Haley Louise Gomez, L. Vigroux, A. Rykala, Eli Dwek, Bernhard Schulz, Maarten Baes, A. Cooray, Matthew Smith, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire astronomique de Strasbourg (ObAS), and Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: individual: NGC4438 [galaxies], Cosmology and Nongalactic Astrophysics (astro-ph.CO), FOS: Physical sciences, DUST, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, galaxies [infrared], infrared: galaxies, POLYCYCLIC AROMATIC-HYDROCARBONS, ABUNDANCES, VIEW, Cluster (physics), Galaxy formation and evolution, Astrophysics::Solar and Stellar Astrophysics, evolution [galaxies], Astrophysics::Galaxy Astrophysics, galaxies: individual: NGC 4438, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], extinction, Hydrogen molecule, Astronomy and Astrophysics, VIRGO CLUSTER, Virgo Cluster, Galaxy, Spire, Physics and Astronomy, NGC 4438, GAS, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics::Earth and Planetary Astrophysics, dust, EMISSION, galaxies: evolution, SYSTEM, NGC-4438, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present Herschel-SPIRE observations of the perturbed galaxy NGC4438 in the Virgo cluster. These images reveal the presence of extra-planar dust up to ~4-5 kpc away from the galaxy's disk. The dust closely follows the distribution of the stripped atomic and molecular hydrogen, supporting the idea that gas and dust are perturbed in a similar fashion by the cluster environment. Interestingly, the extra-planar dust lacks a warm temperature component when compared to the material still present in the disk, explaining why it was missed by previous far-infrared investigations. Our study provides evidence for dust stripping in clusters of galaxies and illustrates the potential of Herschel data for our understanding of environmental effects on galaxy evolution., Comment: 5 pages, 2 figures. Accepted for publication on the A&A Herschel Special Issue
Published: 2010

34. Herschel photometric observations of the low metallicity dwarf galaxy NGC 1705

Author: Asantha Cooray, M. J. Barlow, P. Chanial, George J. Bendo, Ismael Perez-Fournon, M. Trichas, E. Dwek, Gillian S. Wright, Herve Wozniak, Walter Kieran Gear, Robbie Richard Auld, J. J. Bock, L. Vigroux, Jason Glenn, D. Elbaz, Christine D. Wilson, Alessandro Boselli, Diane Cormier, Benjamin L. Schulz, Maarten Baes, Frédéric Galliano, Stephen Anthony Eales, Jonathan Ivor Davies, Laure Ciesla, N. Sacchi, E. E. Rigby, N. Castro-Rodriguez, Michael Pohlen, Jamie Stevens, Seb Oliver, Suzanne C. Madden, Marc Sauvage, Matthew Smith, P. Panuzzo, Matthew Joseph Griffin, L. Spinoglio, A. Rykala, M. Bradford, Haley Louise Gomez, N. Rangwala, Mat Page, K. Okumura, Helene Roussel, David L. Clements, Luca Cortese, Maximilien R. P. Schirm, V. Buat, K. G. Isaak, B. O'Halloran, Mattia Vaccari, Andreas Papageorgiou, Maud Galametz, Werner W. Zeilinger, Sacha Hony, Stéphane Charlot, S. Sundar, Louis Levenson, Nanyao Y. Lu, M. Symeonidis, T. J. Parkin, Laboratoire d'Astrophysique de Marseille (LAM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), dwarf [galaxies], Metallicity, FOS: Physical sciences, Astrophysics, HII-REGIONS, 01 natural sciences, Photometry (optics), POLYCYCLIC AROMATIC-HYDROCARBONS, AMORPHOUS-CARBON, 0103 physical sciences, evolution, Emissivity, 010303 astronomy & astrophysics, QB, Dwarf galaxy, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, extinction, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Wavelength, Star cluster, SPECTRAL ENERGY-DISTRIBUTION, Physics and Astronomy, SPINNING DUST GRAINS, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), STARBURST, Spectral energy distribution, MILKY-WAY, dust, NGC-1705, EMISSION, INTERSTELLAR DUST, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present Herschel SPIRE and PACS photometeric observations of the low metallicity (Z ~ 0.35 solar) nearby dwarf galaxy, NGC 1705, in six wavelength bands as part of the Dwarf Galaxy Survey guaranteed time Herschel Key Program. We confirm the presence of two dominant circumnuclear IR-bright regions surrounding the central super star cluster that had been previously noted at mid-IR wavelengths and in the sub-mm by LABOCA. On constructing a global spectral energy distribution using the SPIRE and PACS photometry, in conjunction with archival IR measurements, we note the presence of an excess at sub-mm wavelengths. This excess suggests the presence of a significant cold dust component within NGC 1705 and was modeled as an additional cold component in the SED. Although alternative explanations for the sub-mm excess beyond 350 microns, such as changes to the dust emissivity cannot be ruled out, the most likely explanation for the observed submillimetre excess is that of an additional cold dust component., 5 pages, 2 figures, accepted for publication in A&A (Herschel special issue)
Published: 2010

35. From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt survey

Author: Alexander Men'shchikov, Pierre Cox, L. Cambrésy, Jin-Zeng Li, Aurora Sicilia-Aguilar, Adam Woodcraft, Marc Sauvage, A. Di Giorgio, Nicola Schneider, Stefano Pezzuto, J. Di Francesco, Jason M. Kirk, Timo Prusti, Alain Abergel, D. Russeil, Helene Roussel, Milena Benedettini, Pierre Royer, Bruce Sibthorpe, C. Waelkens, Th. Henning, J.-P. Baluteau, L. Spinoglio, Vincent Minier, Frédérique Motte, Doris Arzoumanian, Glenn J. White, R. Vavrek, Annie Zavagno, Vera Könyves, Ph. André, Peter Charles Hargrave, Sergio Molinari, M. Attard, Nicolas Peretto, P. Didelon, Sylvain Bontemps, Martin Hennemann, Ralf Launhardt, Oliver Krause, Leonardo Testi, Peter G. Martin, Bruno Merín, J. Le Pennec, J.-Ph. Bernard, Maohai Huang, Herve Aussel, Anaëlle Maury, C. D. Wilson, S. J. Leeks, Matthew Joseph Griffin, Peter A. R. Ade, Derek Ward-Thompson, Paolo Saraceno, Alain Omont, Joris Blommaert, Göran Olofsson, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), School of Physics and Astronomy [Cardiff], Cardiff University, Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), European Southern Observatory (ESO), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), LEOSPHERE France, LEOSPHERE, AUTRES, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), National Astronomical Observatories [Beijing] (NAOC), Chinese Academy of Sciences [Beijing] (CAS), School of Physics and Astronomy, CITA, University of Toronto, Stockholm University, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Royal Observatory Edinburgh (ROE), University of Edinburgh, Antarctic Research a European Network for Astrophysics (ARENA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Observatoire Astronomique de Marseille Provence (OAMP), Université de Provence - Aix-Marseille 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), ITA, GBR, FRA, DEU, and BEL
Subjects: Physics, Gravitational instability, Initial mass function, 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Molecular cloud, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, 01 natural sciences, law.invention, Spire, Polaris, Space and Planetary Science, law, Astrophysics of Galaxies (astro-ph.GA), Core formation, 0103 physical sciences, Protostar, 010303 astronomy & astrophysics, Flare, QB
Abstract: We summarize the first results from the Gould Belt survey, obtained toward the Aquila Rift and Polaris Flare regions during the 'science demonstration phase' of Herschel. Our 70-500 micron images taken in parallel mode with the SPIRE and PACS cameras reveal a wealth of filamentary structure, as well as numerous dense cores embedded in the filaments. Between ~ 350 and 500 prestellar cores and ~ 45-60 Class 0 protostars can be identified in the Aquila field, while ~ unbound starless cores and no protostars are observed in the Polaris field. The prestellar core mass function (CMF) derived for the Aquila region bears a strong resemblance to the stellar initial mass function (IMF), already confirming the close connection between the CMF and the IMF with much better statistics than earlier studies. Comparing and contrasting our Herschel results in Aquila and Polaris, we propose an observationally-driven scenario for core formation according to which complex networks of long, thin filaments form first within molecular clouds, and then the densest filaments fragment into a number of prestellar cores via gravitational instability., 7 pages, 4 figures. Accepted for publication in Astronomy and Astrophysics, Herschel Special Issue
Published: 2010

36. A Spitzer Unbiased Ultradeep Spectroscopic Survey

Author: Kartik Sheth, Timothy Y. Brooke, J. D. T. Smith, Helene Roussel, George Helou, P. N. Appleton, Martin Harwit, Daniel A. Dale, Patrick Ogle, B. Bertincourt, Jean-Loup Puget, and Guilaine Lagache
Subjects: Physics, Spectral signature, Cosmology and Nongalactic Astrophysics (astro-ph.CO), 010504 meteorology & atmospheric sciences, Infrared, Flux, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Stellar classification, 01 natural sciences, Spectral line, Redshift, Space and Planetary Science, 0103 physical sciences, Absorption (electromagnetic radiation), 010303 astronomy & astrophysics, Spectrograph, 0105 earth and related environmental sciences, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We carried out an unbiased, spectroscopic survey using the low-resolution module of the infrared spectrograph (IRS) on board Spitzer targeting two 2.6 square arcminute regions in the GOODS-North field. IRS was used in spectral mapping mode with 5 hours of effective integration time per pixel. One region was covered between 14 and 21 microns and the other between 20 and 35 microns. We extracted spectra for 45 sources. About 84% of the sources have reported detections by GOODS at 24 microns, with a median F_nu(24um) ~ 100 uJy. All but one source are detected in all four IRAC bands, 3.6 to 8 microns. We use a new cross-correlation technique to measure redshifts and estimate IRS spectral types; this was successful for ~60% of the spectra. Fourteen sources show significant PAH emission, four mostly SiO absorption, eight present mixed spectral signatures (low PAH and/or SiO) and two show a single line in emission. For the remaining 17, no spectral features were detected. Redshifts range from z ~ 0.2 to z ~ 2.2, with a median of 1. IR Luminosities are roughly estimated from 24 microns flux densities, and have median values of 2.2 x 10^{11} L_{\odot} and 7.5 x 10^{11} L_{\odot} at z ~ 1 and z ~ 2 respectively. This sample has fewer AGN than previous faint samples observed with IRS, which we attribute to the fainter luminosities reached here., Published in ApJ
Published: 2009

37. The Spitzer Infrared Nearby Galaxies Survey: A High-Resolution Spectroscopy Anthology

Author: Karl D. Gordon, Shawn Staudaher, George Helou, Charles W. Engelbracht, R. C. Kennicutt, E. A. Schlawin, Kartik Sheth, Brent A. Buckalew, Helene Roussel, Daniela Calzetti, J. D. T. Smith, David Hollenbach, Daniel A. Dale, John Moustakas, L. C. Johnson, Lee Armus, Thomas H. Jarrett, Sangeeta Malhotra, S. A. Cohen, Eric J. Murphy, and Caroline Bot
Subjects: Physics, Electron density, Star formation, Metallicity, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Accretion (astrophysics), Spectral line, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, Spectroscopy, Astrophysics::Galaxy Astrophysics
Abstract: High resolution mid-infrared spectra are presented for 155 nuclear and extranuclear regions from the Spitzer Infrared Nearby Galaxies Survey (SINGS). The fluxes for nine atomic forbidden and three molecular hydrogen mid-infrared emission lines are also provided, along with upper limits in key lines for infrared-faint targets. The SINGS sample shows a wide range in the ratio of [SIII]18.71um/[SIII]33.48um, but the average ratio of the ensemble indicates a typical interstellar electron density of 300-400 cm^{-3} on ~23"x15" scales and 500-600 cm^{-3} using ~11"x9" apertures, independent of whether the region probed is a star-forming nuclear, a star-forming extranuclear, or an AGN environment. Evidence is provided that variations in gas-phase metallicity play an important role in driving variations in radiation field hardness, as indicated by [NeIII]15.56um/[NeII]12.81um, for regions powered by star formation. Conversely, the radiation hardness for galaxy nuclei powered by accretion around a massive black hole is independent of metal abundance. Furthermore, for metal-rich environments AGN are distinguishable from star-forming regions by significantly larger [NeIII]15.56um/[NeII]12.81um ratios. Finally, [FeII]25.99um/[NeII]12.81um versus [SiII]34.82um/[SIII]33.48um also provides an empirical method for discerning AGN from normal star-forming sources. However, similar to [NeIII]15.56um/[NeII]12.81um, these mid-infrared line ratios lose their AGN/star-formation diagnostic powers for very low metallicity star-forming systems with hard radiation fields., Accepted for publication in ApJ
Published: 2009

38. Warm Molecular Hydrogen in the Spitzer SINGS Galaxy Sample

Author: Caroline Bot, George Helou, Fabian Walter, R. C. Kennicutt, Helene Roussel, Michele D. Thornley, Daniel A. Dale, J. D. T. Smith, David Hollenbach, Bruce T. Draine, Lee Armus, Daniela Calzetti, Eric J. Murphy, Eva Schinnerer, and C. W. Engelbracht
Subjects: Physics, Infrared, Sample (material), Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Intensity (physics), Thermalisation, Space and Planetary Science, Excited state, Excitation, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract: (simplified) Results on the properties of warm H2 in 57 normal galaxies are derived from H2 rotational transitions, obtained as part of SINGS. This study extends previous extragalactic surveys of H2, the most abundant constituent of the molecular ISM, to more common systems (L_FIR = e7 to 6e10 L_sun) of all morphological and nuclear types. The S(1) transition is securely detected in the nuclear regions of 86% of SINGS galaxies with stellar masses above 10^9.5 M_sun. The derived column densities of warm H2 (T > ~100 K), even though averaged over kiloparsec-scale areas, are commensurate with those of resolved PDRs; the median of the sample is 3e20 cm-2. They amount to between 1% and >30% of the total H2. The power emitted in the sum of the S(0) to S(2) transitions is on average 30% of the [SiII] line power, and ~4e-4 of the total infrared power (TIR) within the same area for star-forming galaxies, which is consistent with excitation in PDRs. The fact that H2 emission scales tightly with PAH emission, even though the average radiation field intensity varies by a factor ten, can also be understood if both tracers originate predominantly in PDRs, either dense or diffuse. A large fraction of the 25 LINER/Sy targets, however, strongly depart from the rest of the sample, in having warmer H2 in the excited states, and an excess of H2 emission with respect to PAHs, TIR and [SiII]. We propose a threshold in H2 to PAH power ratios, allowing the identification of low-luminosity AGNs by an excess H2 excitation. A dominant contribution from shock heating is favored in these objects. Finally, we detect, in nearly half the star-forming targets, non-equilibrium ortho to para ratios, consistent with FUV pumping combined with incomplete ortho-para thermalization by collisions, or possibly non-equilibrium PDR fronts advancing into cold gas., ApJS, in press
Published: 2007

39. The Calibration of Mid-Infrared Star Formation Rate Indicators

Author: Karl D. Gordon, Daniel A. Dale, Kartik Sheth, George Helou, J. D. T. Smith, Daniela Calzetti, George J. Bendo, David Hollenbach, M. Sosey, Robert C. Kennicutt, C. W. Engelbracht, Caroline Bot, Brent A. Buckalew, Helene Roussel, Michele D. Thornley, Eric J. Murphy, George H. Rieke, Lee Armus, Claus Leitherer, Michael W. Regan, Thomas H. Jarrett, Fabian Walter, Lisa J. Kewley, Bruce T. Draine, Aigen Li, John Moustakas, Moire K. M. Prescott, and Martin Meyer
Subjects: Luminous infrared galaxy, Physics, Opacity, Star formation, Metallicity, Astrophysics::High Energy Astrophysical Phenomena, Extinction (astronomy), Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract: With the goal of investigating the degree to which the mid-infrared emission traces the star formation rate (SFR), we analyze Spitzer 8 um and 24 um data of star-forming regions in a sample of 33 nearby galaxies with available HST/NICMOS images in the Paschen-alpha (1.8756 um) emission line. The galaxies are drawn from the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample, and cover a range of morphologies and a factor ~10 in oxygen abundance. Published data on local low-metallicity starburst galaxies and Luminous Infrared Galaxies are also included in the analysis. Both the stellar-continuum-subtracted 8 um emission and the 24 um emission correlate with the extinction-corrected Pa-alpha line emission, although neither relationship is linear. Simple models of stellar populations and dust extinction and emission are able to reproduce the observed non-linear trend of the 24 um emission versus number of ionizing photons, including the modest deficiency of 24 um emission in the low metallicity regions, which results from a combination of decreasing dust opacity and dust temperature at low luminosities. Conversely, the trend of the 8 um emission as a function of the number of ionizing photons is not well reproduced by the same models. The 8 um emission is contributed, in larger measure than the 24 um emission, by dust heated by non-ionizing stellar populations, in agreement with previous findings. Two SFR calibrations, one using the 24 um emission and the other using a combination of the 24 um and H-alpha luminosities (Kennicutt et al. 2007), are presented. No calibration is presented for the 8 um emission, because of its significant dependence on both metallicity and environment. The calibrations presented here should be directly applicable to systems dominated by on-going star formation., Comment: 67 pages, 15 figures, accepted for publication on the Astrophysical Journal; replacement contains: correction to equation 8; important tweaks to equation 9; various typos corrected
Published: 2007

40. Dust Masses, PAH Abundances, and Starlight Intensities in the SINGS Galaxy Sample

Author: Karl D. Gordon, George J. Bendo, J. D. T. Smith, George Helou, David Hollenbach, Daniela Calzetti, Aigen Li, Fabian Walter, Eric J. Murphy, George H. Rieke, Harry I. Teplitz, Daniel A. Dale, Robert C. Kennicutt, Charles W. Engelbracht, Helene Roussel, John Moustakas, Caroline Bot, Bruce T. Draine, Kartik Sheth, and Lee Armus
Subjects: Physics, Spiral galaxy, 010504 meteorology & atmospheric sciences, Metallicity, Milky Way, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Galaxy, Starlight, Photometry (optics), 13. Climate action, Space and Planetary Science, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences
Abstract: Physical dust models are presented for 65 galaxies in the SINGS survey that are strongly detected in the four IRAC bands and three MIPS bands. For each galaxy we estimate (1) the total dust mass, (2) the fraction of the dust mass contributed by PAHs, and (3) the intensity of the starlight heating the dust grains. We find that spiral galaxies have dust properties resembling the dust in the local region of the Milky Way, with similar dust-to-gas ratio, and similar PAH abundance. The observed SEDs, including galaxies with SCUBA photometry, can be reproduced by dust models that do not require "cold" (T8.1, grains contain a substantial fraction of interstellar Mg, Si and Fe. Galaxies with A_O8.1 have a median q_PAH=3.55%. The derived dust masses favor a value X_CO approx 4e20 cm^{-2}(K kms)^{-1} for the CO to H_2 conversion factor. Except for some starbursting systems (Mrk33, Tolo89, NGC3049), dust in the diffuse ISM dominates the IR power., Accepted for publication in the Astrophysical Journal
Published: 2007

41. Dust and Atomic Gas in Dwarf Irregular Galaxies of the M81 Group: The SINGS and THINGS view

Author: George J. Bendo, Karl D. Gordon, Martin Meyer, Frank Bigiel, Michael W. Regan, Fabian Walter, Helene Roussel, Michele D. Thornley, J. D. T. Smith, George Helou, Janice C. Lee, David Hollenbach, Daniel A. Dale, Lee Armus, W. J. G. de Blok, R. C. Kennicutt, John Moustakas, Aigen Li, Elias Brinks, Daniela Calzetti, B. T. Draine, Eric J. Murphy, George H. Rieke, Charles W. Engelbracht, and John M. Cannon
Subjects: Physics, Spiral galaxy, 010504 meteorology & atmospheric sciences, Star formation, Metallicity, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Galaxy, Luminosity, Space and Planetary Science, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Irregular galaxy, Spectroscopy, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Dwarf galaxy
Abstract: [abridged] We present observations of the dust and atomic gas phase in seven dwarf irregular galaxies of the M81 group from the SINGS and THINGS surveys. The Spitzer observations provide a first glimpse of the nature of the non-atomic ISM in these metal-poor (Z~0.1 Z_sun), quiescent (SFR~0.001-0.1 M_sun/yr) dwarf galaxies. Dust emission is detected in five out of the seven targets. Most detected dust emission is restricted to HI column densities >1x10^21 cm^-2. Spitzer spectroscopy of two regions in the brightest galaxies (IC 2574 and Holmberg II) show distinctly different spectral shapes. The spectrum of IC 2574 shows aromatic features that are less luminous (relative to the FIR luminosity) compared to an average SINGS spiral galaxy by a factor of \~7 . The aromatic features in Holmberg~II (which has only a slightly lower gas-phase metallicity) are fainter than in IC 2574 by an order of magnitude. This result emphazises that the strength of the aromatic features is not a simple linear function of metallicity. We estimate dust masses of ~10^4-10^6 M_sun for the M81 dwarf galaxies, resulting in an average dust--to--gas ratio (M_dust/M_HI) of ~3x10^-4 (1.5x10^-3 if only the HI that is associated with dust emission is considered); this is an order of magnitude lower than the typical value derived for the SINGS spirals. The dwarf galaxies are underluminous per unit star formation rate at 70um as compared to the more massive galaxies in SINGS by a factor of ~2. However, the average 70um/160um ratio in the sample dwarf galaxies is higher than what is found in the other galaxies of the SINGS sample. This can be explained by a combination of a lower dust content in conjunction with a higher dust temperature in the dwarfs., Accepted for publication in the Astrohysical Journal. High resolution version available at: http://www.mpia.de/homes/walter/preprint_walter_highres.pdf
Published: 2007
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42. THE MULTI-PHASE COLD FOUNTAIN IN M82 REVEALED BY A WIDE, SENSITIVE MAP OF THE MOLECULAR INTERSTELLAR MEDIUM

Author: Alberto D. Bolatto, Miroslava Dessauges-Zavadsky, Fabian Walter, Axel Weiss, Helene Roussel, Paul Martini, Adam K. Leroy, Jürgen Ott, Karl Schuster, and Karin Sandstrom
Subjects: Physics, Stellar wind, Interstellar medium, Carbon oxide, Space and Planetary Science, Multi phase, Intergalactic medium, Astronomy and Astrophysics, Astrophysics, Fountain, Galaxy, Cosmic dust
Published: 2015

43. The Effect of Star Formation on the Far-Infrared--Radio Correlation within Galaxies

Author: George J. Bendo, Jeffrey D. P. Kenney, Daniel A. Dale, Eric J. Murphy, Fabian Walter, Robert Braun, Brent A. Buckalew, Helene Roussel, Michele D. Thornley, Daniela Calzetti, J. D. T. Smith, Lee Armus, Bruce T. Draine, R. C. Kennicutt, George Helou, and Charles W. Engelbracht
Subjects: Physics, Infrared, Star formation, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Synchrotron radiation, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Radio telescope, Supernova, Far infrared, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Surface brightness, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Using data obtained for twelve galaxies as part of the {\it Spitzer} Infrared Nearby Galaxies Survey (SINGS) and the Westerbork Synthesis Radio Telescope (WSRT)-SINGS radio continuum survey, we study how star formation activity affects the far-infrared (FIR)--radio correlation {\it within} galaxies by testing a phenomenological model, which describes the radio image as a smeared version of the FIR image. The physical basis of this description is that cosmic-ray (CR) electrons will diffuse measurably farther than the mean free path of dust-heating photons before decaying by synchrotron radiation. This description works well in general. Galaxies with higher infrared surface brightnesses have best-fit smoothing scale-lengths of a few hundred parsecs, substantially shorter than those for lower surface brightness galaxies. We interpret this result to suggest that galaxies with higher disk averaged star formation rates have had a recent episode of enhanced star formation and are characterized by a higher fraction of young CR electrons that have traveled only a few hundred parsecs from their acceleration sites in supernova remnants compared to galaxies with lower star formation activity., 5 pages, 3 figures; Accepted for publication in ApJ Letters
Published: 2006

44. The opaque nascent starburst in NGC 1377: Spitzer SINGS observations

Author: Michael W. Regan, Fabian Walter, Karl D. Gordon, George J. Bendo, Helene Roussel, J. D. T. Smith, David Hollenbach, Eric J. Murphy, George H. Rieke, Kartik Sheth, Daniel A. Dale, George Helou, C. W. Engelbracht, Lee Armus, Martin Meyer, Henrik Spoon, R. C. Kennicutt, John Moustakas, and Bruce T. Draine
Subjects: Physics, Infrared excess, Opacity, Infrared, Astrophysics::High Energy Astrophysical Phenomena, Photodissociation, Astrophysics (astro-ph), Infrared spectroscopy, FOS: Physical sciences, Astronomy and Astrophysics, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Accretion (astrophysics), Galaxy, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Caltech Library Services, Astrophysics::Galaxy Astrophysics
Abstract: We analyze extensive data on NGC1377 from the Spitzer Infrared Nearby Galaxies Survey (SINGS). Within the category of nascent starbursts, that we previously selected by their infrared to radio continuum ratios in large excess of the average and their hot dust, NGC1377 has the largest infrared excess yet measured. Optical imaging reveals a morphological distortion suggestive of a recent accretion event. Infrared spectroscopy reveals a compact and opaque source dominated by a hot, self-absorbed continuum (tau ~ 20 in the 10 micron silicate band). We provide physical evidence against non-stellar activity being the heating source. HII regions are detected through the single [NeII] line, probing 85% of ionizing photons are suppressed by dust. The only other detected emission features are molecular hydrogen lines, arguably excited mainly by shocks, besides photodissociation regions, and weak aromatic bands. The new observations support our interpretation in terms of an extremely young starburst (, accepted for publication in ApJ ; 28 pages of text + 2 tables + 14 figures
Published: 2006

45. Spitzer and JCMT Observations of the Active Galactic Nucleus in the Sombrero Galaxy (NGC 4594)

Author: John M. Cannon, Kartik Sheth, Karl D. Gordon, Daniel A. Dale, George Helou, Fabian Walter, R. C. Kennicutt, Brent A. Buckalew, Helene Roussel, J. D. T. Smith, Charles W. Engelbracht, Eric J. Murphy, David Hollenbach, Daniela Calzetti, Bruce T. Draine, George J. Bendo, and Robert D. Joseph
Subjects: Physics, Active galactic nucleus, Star formation, Infrared, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Spectral line, Galaxy, Luminosity, Space and Planetary Science, Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract: We present Spitzer 3.6-160 micron images, Spitzer mid-infrared spectra, and JCMT SCUBA 850 micron images of the Sombrero Galaxy (NGC 4594), an Sa galaxy with a 10^9 M_solar low luminosity active galactic nucleus (AGN). The brightest infrared sources in the galaxy are the nucleus and the dust ring. The spectral energy distribution of the AGN demonstrates that, while the environment around the AGN is a prominent source of mid-infrared emission, it is a relatively weak source of far-infrared emission, as had been inferred for AGN in previous research. The weak nuclear 160 micron emission and the negligible polycyclic aromatic hydrocarbon emission from the nucleus also implies that the nucleus is a site of only weak star formation activity and the nucleus contains relatively little cool interstellar gas needed to fuel such activity. We propose that this galaxy may be representative of a subset of low ionization nuclear emission region galaxies that are in a quiescent AGN phase because of the lack of gas needed to fuel circumnuclear star formation and Seyfert-like AGN activity. Surprisingly, the AGN is the predominant source of 850 micron emission. We examine the possible emission mechanisms that could give rise to the 850 micron emission and find that neither thermal dust emission, CO line emission, bremsstrahlung emission, nor the synchrotron emission observed at radio wavelengths can adequately explain the measured 850 micron flux density by themselves. The remaining possibilities for the source of the 850 micron emission include a combination of known emission mechanisms, synchrotron emission that is self-absorbed at wavelengths longer than 850 microns, or unidentified spectral lines in the 850 micron band., Comment: Accepted to ApJ, 2006
Published: 2006
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46. An Initial Look at the Far Infrared-Radio Correlation within Nearby Star-forming Galaxies using the Spitzer Space Telescope

Author: Karl D. Gordon, Thomas Jarrett, Jeffrey D. P. Kenney, J. D. T. Smith, George Helou, R. C. Kennicutt, Tom Oosterloo, Lee Armus, Daniel A. Dale, George J. Bendo, Lisa J. Kewley, Fabian Walter, Bruce T. Draine, Marcia J. Rieke, Martin Meyer, Claus Leitherer, Robert Braun, David Hollenbach, Daniela Calzetti, John M. Cannon, Michael W. Regan, Kartik Sheth, Charles W. Engelbracht, Helene Roussel, Michele D. Thornley, Eric J. Murphy, George H. Rieke, and Aigen Li
Subjects: Physics, Star formation, Infrared, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Interstellar medium, Far infrared, Spitzer Space Telescope, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Surface brightness, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: (Abridged) We present an initial look at the far infrared-radio correlation within the star-forming disks of four nearby, nearly face-on galaxies (NGC 2403, NGC 3031, NGC 5194, and NGC 6946). Using Spitzer MIPS imaging and WSRT radio continuum data, observed as part of the Spitzer Infrared Nearby Galaxies Survey (SINGS), we are able to probe variations in the logarithmic 24mu/22cm (q_24) and 70mu/22cm (q_70) surface brightness ratios across each disk at sub-kpc scales. We find general trends of decreasing q_24 and q_70 with declining surface brightness and with increasing radius. The residual dispersion around the trend of q_24 and q_70 versus surface brightness is smaller than the residual dispersion around the trend of q_24 and q_70 versus radius, on average by ~0.1 dex, indicating that the distribution of star formation sites is more important in determining the infrared/radio disk appearance than the exponential profiles of disks. We have also performed preliminary phenomenological modeling of cosmic ray electron (CRe^-) diffusion using an image-smearing technique, and find that smoothing the infrared maps improves their correlation with the radio maps. Exponential kernels tend to work better than Gaussian kernels which suggests that additional processes besides simple random-walk diffusion in three dimensions must affect the evolution of CRe^-s. The best fit smoothing kernels for the two less active star-forming galaxies (NGC 2403 and NGC 3031) have much larger scale-lengths than those of the more active star-forming galaxies (NGC 5194 and NGC 6946). This difference may be due to the relative deficit of recent CRe^- injection into the interstellar medium (ISM) for the galaxies having largely quiescent disks., 41 pages including 6 tables and 12 figures; accepted for publication in the Astrophysical Journal. A full-resolution color version can be found at http://www.astro.yale.edu/murphy/a-ph/murphy_FIR-radio.pdf ; Corrected typos
Published: 2005

47. An atlas of mid-infrared dust emission in spiral galaxies

Author: Paola Mazzei, Helene Roussel, Marc Sauvage, Pascal Gallais, L. Vigroux, S. C. Madden, T. Hawarden, James Lequeux, A. Bosma, and C. Bonoli
Subjects: Physics, Astrophysics and Astronomy, Spiral galaxy, Star formation, Astrophysics (astro-ph), Mid infrared, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, medicine.anatomical_structure, Space and Planetary Science, Atlas (anatomy), medicine, Astrophysics::Earth and Planetary Astrophysics, Spiral, Astrophysics::Galaxy Astrophysics, Data reduction, Dust emission
Abstract: We present maps of dust emission at 7 microns and 15 microns/7 microns intensity ratios of selected regions in 43 spiral galaxies observed with ISOCAM. This atlas is a complement to studies based on these observations, dealing with star formation in centers of barred galaxies and in spiral disks. It is accompanied by a detailed description of data reduction and an inventory of generic morphological properties in groups defined according to bar strength and HI gas content., 38 pages, 51 figure files, uses aa.cls, apj.bst, graphicx.sty and natbib.sty -- accepted for publication in A&A
Published: 2001

48. The relationship between star formation rates and mid-infrared emission in galactic disks

Author: Marc Sauvage, A. Bosma, L. Vigroux, Helene Roussel, Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Observatoire Astronomique de Marseille Provence (OAMP), Université de Provence - Aix-Marseille 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and ISOCAM
Subjects: galaxies: spiral, 010504 meteorology & atmospheric sciences, Infrared, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Spiral, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Line (formation), Physics, infrared: ISM, [PHYS]Physics [physics], Spiral galaxy, stars: formation, Star formation, Astrophysics (astro-ph), Photodissociation, Astronomy and Astrophysics, Galaxy, Wavelength, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], galaxies: ISM
Abstract: The Halpha and mid-infrared mean disk surface brightnesses are compared in a sample of nearby spirals observed by ISOCAM. This shows that, in spiral disks, dust emission at 7 and 15 microns provides a reasonable star formation tracer. The fact that the 15 to 7 micron flux ratio is nearly constant in various global exciting conditions indicates a common origin, namely the aromatic infrared band carriers, and implies that at these wavelengths, dust emission from the disks of normal galaxies is dominated by photodissociation regions and not by HII regions themselves. We use this newly-found correlation between the mid-infrared and the Halpha line to investigate the nature of the link between the far-infrared (60 and 100 microns) and Halpha. Although the separation of the central regions from the disk is impossible to achieve in the far-infrared, we show that a circumnuclear contribution to the dust emission, having no equivalent counterpart in Halpha, is most likely responsible for the well-known non-linearity between far-infrared and Halpha fluxes in spiral galaxies. We derive a calibration of 7 and 15 micron fluxes in terms of star formation rates from a primary calibration of Halpha in the literature, and also outline the applicability limits of the proposed conversion, which should not be blindly extrapolated to objects whose nature is unknown., 13 pages, 7 figures, accepted for publication in A&A ; small errors corrected and references updated
Published: 2001

49. The impact of bars on the mid-infrared dust emission of spiral galaxies: global and circumnuclear properties

Author: Marc Sauvage, A. Bosma, C. Bonoli, Suzanne C. Madden, Helene Roussel, L. Vigroux, Paola Mazzei, Pascal Gallais, and T. Hawarden
Subjects: Physics, Thermal equilibrium, Point spread function, Brightness, Spiral galaxy, Star formation, Infrared, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Gravitational potential, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We study the mid-infrared properties of a sample of 69 nearby spiral galaxies, selected to avoid Seyfert activity contributing a significant fraction of the central energetics, or strong tidal interaction, and to have normal infrared luminosities. These observations were obtained with ISOCAM, which provides an angular resolution of the order of 10 arcsec (half-power diameter of the point spread function) and low-resolution spectro-imaging information. Between 5 and 18 microns, we mainly observe two dust phases, aromatic infrared bands and very small grains, both out of thermal equilibrium. On this sample, we show that the global F15/F7 colors of galaxies are very uniform, the only increase being found in early-type strongly barred galaxies, consistent with previous IRAS studies. The F15/F7 excesses are unambiguously due to galactic central regions where bar-induced starbursts occur. However, the existence of strongly barred early-type galaxies with normal circumnuclear colors indicates that the relationship between a distortion of the gravitational potential and a central starburst is not straightforward. As the physical processes at work in central regions are in principle identical in barred and unbarred galaxies, and since this is where the mid-infrared activity is mainly located, we investigate the mid-infrared circumnuclear properties of all the galaxies in our sample. We show how surface brightnesses and colors are related to both the available molecular gas content and the mean age of stellar populations contributing to dust heating. Therefore, the star formation history in galactic central regions can be constrained by their position in a color-surface brightness mid-infrared diagram., Comment: 22 pages, 25 figures, accepted for publication in A&A ; small errors corrected and references updated
Published: 2001
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50. TheHerschelSpace Observatory view of dust in M81

Author: Marc Sauvage, N. Lu, Pierre Chanial, Walter Kieran Gear, L. Vigroux, Pasquale Panuzzo, M. Symeonidis, Herve Wozniak, Diane Cormier, George J. Bendo, B. O'Halloran, James J. Bock, M. J. Barlow, Werner W. Zeilinger, Jamie Stevens, Mattia Vaccari, E. E. Rigby, Stephane Charlot, Helene Roussel, David L. Clements, Luca Cortese, Naseem Rangwala, T. J. Parkin, Michael Pohlen, N. Castro-Rodriguez, Matthew Joseph Griffin, Matthew Smith, Sacha Hony, S. Sundar, Maud Galametz, Alessandro Boselli, A. Cooray, Gillian S. Wright, Christine D. Wilson, M. Bradford, Haley Louise Gomez, Stephen Anthony Eales, Koryo Okumura, Andreas Papageorgiou, Eli Dwek, Maximilien R. P. Schirm, Laure Ciesla, Kate Gudrun Isaak, Maarten Baes, N. Sacchi, Suzanne C. Madden, L. R. Levenson, Benjamin L. Schulz, Markos Trichas, Seb Oliver, V. Buat, Ismael Perez-Fournon, Mat Page, Jason Glenn, Robbie Richard Auld, D. Elbaz, Frédéric Galliano, L. Spinoglio, A. Rykala, Jonathan Ivor Davies, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire astronomique de Strasbourg (ObAS), and Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: galaxies: spiral, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Active galactic nucleus, TELESCOPE, H-ALPHA, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, THINGS, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, STAR-FORMATION RATES, individual: M81 [galaxies], galaxies: individual: M81, Bulge, Astrophysics::Solar and Stellar Astrophysics, Surface brightness, FIELD, Astrophysics::Galaxy Astrophysics, QB, Physics, Spiral galaxy, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], ISM [galaxies], Spectral density, Astronomy and Astrophysics, Radius, Space observatory, GALAXIES, SPITZER, Stars, spiral [galaxies], Physics and Astronomy, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, EMISSION, galaxies: ISM, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We use Herschel Space Observatory data to place observational constraints on the peak and Rayleigh-Jeans slope of dust emission observed at 70-500 microns in the nearby spiral galaxy M81. We find that the ratios of wave bands between 160 and 500 microns are primarily dependent on radius but that the ratio of 70 to 160 micron emission shows no clear dependence on surface brightness or radius. These results along with analyses of the spectral energy distributions imply that the 160-500 micron emission traces 15-30 K dust heated by evolved stars in the bulge and disc whereas the 70 micron emission includes dust heated by the active galactic nucleus and young stars in star forming regions., Accepted for A & A Herschel special issue
Published: 2010

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