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1. Compact and high excitation molecular clumps in the extended ultraviolet disk of M83.

Author

Koda, Jin, Combes, Françoise, Rubio, Monica, Andersen, Morten, Bigiel, Frank, Gil de Paz, Armando, Junais, Lee, Amanda M, Meyer, Jennifer Donovan, Morokuma-Matsui, Kana, Yagi, Masafumi, and Zavagno, Annie

Subjects
STELLAR evolution, STAR formation, GALAXY formation, SPATIAL resolution, GALAXIES
Abstract

Context. The extended ultraviolet (XUV) disks of nearby galaxies show ongoing massive-star formation, but their parental molecular clouds remain mostly undetected despite searches in CO(1–0) and CO(2–1). The recent detection of 23 clouds in the higher excitation transition CO(3–2) within the XUV disk of M83 thus requires an explanation. Aims. We test the hypothesis introduced to explain the non-detections and recent detection simultaneously: The clouds in XUV disks have a clump-envelope structure similar to those in Galactic star-forming clouds, having dense star-forming clumps (or concentrations of multiple clumps) at their centers, which predominantly contribute to the CO(3–2) emission and are surrounded by less dense envelopes, where CO molecules are photo-dissociated due to the low-metallicity environment there. Methods. We utilize new high-resolution ALMA CO(3–2) observations of a subset (11) of the 23 clouds in the XUV disk of M83. Results. We confirm the compactness of the CO(3–2)-emitting dense clumps (or their concentrations), finding clump diameters below the spatial resolution of 6–9 pc. This is similar to the size of the dense gas region in the Orion A molecular cloud, a local star-forming cloud with massive-star formation. Conclusions. The dense star-forming clumps are common between normal and XUV disks. This may also indicate that once the cloud structure is set, the process of star formation is governed by the cloud's internal physics rather than by external triggers. This simple model explains the current observations of clouds with ongoing massive-star formation, although it may require some adjustment, for example including the effect of cloud evolution, to describe star formation in molecular clouds more generally. [ABSTRACT FROM AUTHOR]

Published
2024
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4. The SOFIA FEEDBACK [CII] Legacy Survey: Rapid molecular cloud dispersal in RCW 79

Author

Bonne, L., primary, Kabanovic, S., additional, Schneider, N., additional, Zavagno, A., additional, Keilmann, E., additional, Simon, R., additional, Buchbender, C., additional, Güsten, R., additional, Jacob, A. M., additional, Jacobs, K., additional, kavak, U., additional, Polles, F. L., additional, Tiwari, M., additional, Wyrowski, F., additional, and Tielens, A. G. G. M., additional

Published
2023
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5. Stellar feedback in the star formation–gas density relation: Comparison between simulations and observations.

Author

Suin, P., Zavagno, A., Colman, T., Hennebelle, P., Verliat, A., and Russeil, D.

Subjects
*DENSITY of stars, *STELLAR evolution, *STELLAR radiation, *HIGH mass stars, *SUPERGIANT stars
Abstract

Context. The impact of stellar feedback on the Kennicutt–Schmidt (KS) law, which relates the star formation rate (SFR) to the surface gas density, is a topic of ongoing debate. The interpretation of high-resolution observations of individual clouds is challenging due to the various processes at play simultaneously and inherent biases. Therefore, a numerical investigation is necessary to understand the role of stellar feedback and identify observable signatures. Aims. In this study we investigate the impact of stellar feedback on the KS law, aiming to identify distinct signatures that can be observed and analysed. By employing magnetohydrodynamic simulations of an isolated cloud, we specifically isolate the effects of high-mass star radiation feedback and protostellar jets. High-resolution numerical simulations are a valuable tool for isolating the impact of stellar feedback on the star formation process, while also allowing us to assess how observational biases may affect the derived relation. Methods. We used high-resolution (<0.01 pc) magnetohydrodynamic numerical simulations of a 104M⊙ cloud and followed its evolution under different feedback prescriptions. The set of simulations contained four types of feedback: one with only protostellar jets, one with ionising radiation from massive stars (>8 M⊙), one with the combination of the two, and one without any stellar feedback. In order to compare these simulations with the existing observational results, we analysed their evolution by adopting the same techniques applied in the observational studies. Then, we simulated how the same analyses would change if the data were affected by typical observational biases: counting young stellar objects (YSO) to estimate the SFR, the limited resolution for the column density maps, and a sensitivity threshold for detecting faint embedded YSOs. Results. Our analysis reveals that the presence of stellar feedback strongly influences the shape of the KS relation and the star formation efficiency per free-fall time (ϵff). The impact of feedback on the relation is primarily governed by its influence on the cloud's structure. Additionally, the evolution of ϵff throughout the star formation event suggests that variations in this quantity can mask the impact of feedback in observational studies that do not account for the evolutionary stage of the clouds. Although the ϵff measured in our clouds is higher than what is usually observed in real clouds, upon applying prescriptions to mimic observational biases we recover a good agreement with the expected values. From that, we can infer that observations tend to underestimate the total SFR. Moreover, this likely indicates that the physics included in our simulations is sufficient to reproduce the basic mechanisms that contribute to setting ϵff. Conclusions. We demonstrate the interest of employing numerical simulations to address the impact of early feedback on star formation laws and to correctly interpret observational data. This study will be extended to other types of molecular clouds and ionising stars, sampling different feedback strengths, to fully characterise the impact of H II regions on star formation. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Supervised machine learning on Galactic filaments

Author

Zavagno, A., primary, Dupé, F.-X., additional, Bensaid, S., additional, Schisano, E., additional, Li Causi, G., additional, Gray, M., additional, Molinari, S., additional, Elia, D., additional, Lambert, J.-C., additional, Brescia, M., additional, Arzoumanian, D., additional, Russeil, D., additional, Riccio, G., additional, and Cavuoti, S., additional

Published
2023
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7. Filamentary structures of ionized gas in Cygnus X

Author

Emig, K. L., primary, White, G. J., additional, Salas, P., additional, Karim, R. L., additional, van Weeren, R. J., additional, Teuben, P. J., additional, Zavagno, A., additional, Chiu, P., additional, Haverkorn, M., additional, Oonk, J. B. R., additional, Orrú, E., additional, Polderman, I. M., additional, Reich, W., additional, Röttgering, H. J. A., additional, and Tielens, A. G. G. M., additional

Published
2022
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8. Self-absorption in [C II], 12CO, and H II in RCW120

Author

Kabanovic, S., primary, Schneider, N., additional, Ossenkopf-Okada, V., additional, Falasca, F., additional, Güsten, R., additional, Stutzki, J., additional, Simon, R., additional, Buchbender, C., additional, Anderson, L., additional, Bonne, L., additional, Guevara, C., additional, Higgins, R., additional, Koribalski, B., additional, Luisi, M., additional, Mertens, M., additional, Okada, Y., additional, Röllig, M., additional, Seifried, D., additional, Tiwari, M., additional, Wyrowski, F., additional, Zavagno, A., additional, and Tielens, A. G. G. M., additional

Published
2022
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9. Velocity structure of the 50 pc long NGC 6334 filamentary cloud

Author

Arzoumanian, Doris, primary, Russeil, Delphine, additional, Zavagno, Annie, additional, Chun-Yuan Chen, Michael, additional, André, Philippe, additional, Inutsuka, Shu-ichiro, additional, Misugi, Yoshiaki, additional, Sánchez-Monge, Álvaro, additional, Schilke, Peter, additional, Men’shchikov, Alexander, additional, and Kohno, Mikito, additional

Published
2022
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10. Probing the structure of a massive filament: ArTéMiS 350 and 450 μm mapping of the integral-shaped filament in Orion A

Author

Schuller, F., primary, André, Ph., additional, Shimajiri, Y., additional, Zavagno, A., additional, Peretto, N., additional, Arzoumanian, D., additional, Csengeri, T., additional, Könyves, V., additional, Palmeirim, P., additional, Pezzuto, S., additional, Rigby, A., additional, Roussel, H., additional, Ajeddig, H., additional, Dumaye, L., additional, Gallais, P., additional, Le Pennec, J., additional, Martignac, J., additional, Mattern, M., additional, Revéret, V., additional, Rodriguez, L., additional, and Talvard, M., additional

Published
2021
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11. Probing the structure of a massive filament: ArTéMiS 350 and 450 micron mapping of the integral-shaped filament in Orion A

Author

Schuller, F., Andre, Ph., Shimajiri, Y., Zavagno, A., Peretto, N., Arzoumanian, D., Csengeri, T., Konyves, Vera, Palmeirim, P., Et, Al, Schuller, F., Andre, Ph., Shimajiri, Y., Zavagno, A., Peretto, N., Arzoumanian, D., Csengeri, T., Konyves, Vera, Palmeirim, P., and Et, Al

Abstract

Context. The Orion molecular cloud is the closest region of high-mass star formation. It is an ideal target for investigating the detailed structure of massive star-forming filaments at high resolution and the relevance of the filament paradigm for the earliest stages of intermediate- to high-mass star formation. Aims. Within the Orion A molecular cloud, the integral-shaped filament (ISF) is a prominent, degree-long structure of dense gas and dust with clear signs of recent and ongoing high-mass star formation. Our aim is to characterise the structure of this massive filament at moderately high angular resolution (800 or ∼ 0.016 pc) in order to measure the intrinsic width of the main filament, down to scales well below 0.1 pc, which has been identified as the characteristic width of filaments. Methods. We used the ArTéMiS bolometer camera at APEX to map a ∼0.6×0.2 deg2 region covering OMC-1, OMC-2, and OMC-3 at 350 and 450 µm. We combined these data with Herschel-SPIRE maps to recover extended emission. The combined Herschel�ArTéMiS maps provide details on the distribution of dense cold material, with a high spatial dynamic range, from our 800 resolution up to the transverse angular size of the map, ∼ 10–150. By combining Herschel and ArTéMiS data at 160, 250, 350, and 450 µm, we constructed high-resolution temperature and H2 column density maps. We extracted radial intensity profiles from the column density map in several representative portions of the ISF, which we fitted with Gaussian and Plummer models to derive their intrinsic widths. We also compared the distribution of material traced by ArTéMiS with that seen in the higher-density tracer N2H+(1–0) that was recently observed with the ALMA interferometer. Results. All the radial profiles that we extracted show a clear deviation from a Gaussian, with evidence for an inner plateau that had not previously been seen clearly using Herschel-only data. We measure intrinsic half-power widths in the range 0.06 to 0.11

Published
2021

12. The role of Galactic H II regions in the formation of filaments

Author

Nicolas Peretto, M. Figueira, Alexander Men'shchikov, Ph. André, Y. Shimajiri, D. Russeil, P. Palmeirim, Nicola Schneider, Vera Konyves, Annie Zavagno, H. Roussel, Timea Csengeri, S. N. Zhang, Gary A. Fuller, Frederic Schuller, Doris Arzoumanian, 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 Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), 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 de Paris (UP), Leibniz-Institut für Astrophysik Potsdam (AIP), School of Physics and Astronomy [Cardiff], Cardiff University, Kagoshima University, Instituto de Astrofísica e Ciências do Espaço (IASTRO), 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), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], Jeremiah Horrocks Institute for Mathematics, Physics and Astronomy [Preston], University of Central Lancashire [Preston] (UCLAN), 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), University Hospital of Cologne [Cologne], Supports from the French national programs on stellar and ISM physics (PNPS and PCMI)., Funding from the European Union’s Horizon 2020 research and innovation programmeunder grant agreement No 730562 [RadioNet]., ANR-16-CE92-0035,GENESIS,GENeration et Evolution des Structures du milieu InterStellaire(2016), 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), ANR-05-BLAN-0215,ARTEMIS,ARchitectures de bolomètres pour des TElescopes à grand champ de vue dans le domaine sub-MIllimétrique au Sol(2005), ANR-11-LABX-0013,FOCUS,Des détecteurs pour Observer l'Univers(2011), and European Project: 291294,EC:FP7:ERC,ERC-2011-ADG_20110209,ORISTARS(2012)

Subjects
010504 meteorology & atmospheric sciences, Shell (structure), FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, Protein filament, ISM: individual objects: RCW 120, Ionization, 0103 physical sciences, H II regions, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, F990, stars: formation, Star formation, Resolution (electron density), Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Full width at half maximum, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), submillimeter: ISM, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

Massive stars and their associated ionized (HII) regions could play a key role in the formation and evolution of filaments that host star formation. However, the properties of filaments that interact with H regions are still poorly known. To investigate the impact of HII regions on the formation of filaments, we imaged the Galactic HII region RCW 120 and its surroundings where active star formation takes place and where the role of ionization feedback on the star formation process has already been studied. We used the ArT\'eMiS camera on the APEX telescope and combined the ArT\'eMiS data at 350 and 450 microns with Herschel-SPIRE/HOBYS. We studied the dense gas distribution around RCW 120 with a resolution of 8 arcsec (0.05 pc at a distance of 1.34 kpc). Our study allows us to trace the median radial intensity profile of the dense shell of RCW 120. This profile is asymmetric, indicating a clear compression from the HII region on the inner part of the shell. The profile is observed to be similarly asymmetric on both lateral sides of the shell, indicating a homogeneous compression over the surface. On the contrary, the profile analysis of a radial filament associated with the shell, but located outside of it, reveals a symmetric profile, suggesting that the compression from the ionized region is limited to the dense shell. The mean intensity profile of the internal part of the shell is well fitted by a Plummer like profile with a deconvolved Gaussian FWHM of 0.09 pc, as observed for filaments in low-mass star-forming regions. This study suggests that compression exerted by HII regions may play a key role in the formation of filaments and may further act on their hosted star formation. ArT\'eMiS data also suggest that RCW 120 might be a 3D ring, rather than a spherical structure, Comment: 8 pages, 8 figures, accepted by A&A

Published
2020
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13. The role of Galactic H iiregions in the formation of filaments High-resolution submilimeter imaging of RCW 120 with ArTéMiS

Author

Zavagno, A., Andre, Ph., Schuller, F., Peretto, N., Shimajiri, Y., Arzoumanian, D., Csengeri, T., Figueira, M., Konyves, Vera, Et, Al, Zavagno, A., Andre, Ph., Schuller, F., Peretto, N., Shimajiri, Y., Arzoumanian, D., Csengeri, T., Figueira, M., Konyves, Vera, and Et, Al

Abstract

Context. Massive stars and their associated ionized (H ii) regions could play a key role in the formation and evolution of filaments that host star formation. However, the properties of filaments that interact with H ii regions are still poorly known. Aims. To investigate the impact of H ii regions on the formation of filaments, we imaged the Galactic H ii region RCW 120 and its surroundings where active star formation takes place and where the role of ionization feedback on the star formation process has already been studied. Methods. We used the large-format bolometer camera ArTéMiS on the APEX telescope and combined the high-resolution ArTéMiS data at 350 µm and 450 µm with Herschel-SPIRE/HOBYS data at 350 and 500 µm to ensure good sensitivity to a broad range of spatial scales. This allowed us to study the dense gas distribution around RCW 120 with a resolution of 800 or 0.05 pc at a distance of 1.34 kpc. Results. Our study allows us to trace the median radial intensity profile of the dense shell of RCW 120. This profile is asymmetric, indicating a clear compression from the H ii region on the inner part of the shell. The profile is observed to be similarly asymmetric on both lateral sides of the shell, indicating a homogeneous compression over the surface. On the contrary, the profile analysis of a radial filament associated with the shell, but located outside of it, reveals a symmetric profile, suggesting that the compression from the ionized region is limited to the dense shell. The mean intensity profile of the internal part of the shell is well fitted by a Plummerlike profile with a deconvolved Gaussian full width at half maximum (FWHM) of 0.09 pc, as observed for filaments in low-mass star-forming regions. Conclusions. Using ArTéMiS data combined with Herschel-SPIRE data, we found evidence for compression from the inner part of the RCW 120 ionized region on the surrounding dense shell. This compression is accompanied with a significant (factor 5) increase

Published
2020

14. Distance of Hi-GAL sources

Author

Mège, P., primary, Russeil, D., additional, Zavagno, A., additional, Elia, D., additional, Molinari, S., additional, Brunt, C. M., additional, Butora, R., additional, Cambresy, L., additional, Di Giorgio, A. M., additional, Fenouillet, T., additional, Fukui, Y., additional, Lambert, J. C., additional, Makai, Z., additional, Merello, M., additional, Meunier, J. C., additional, Molinaro, M., additional, Moreau, C., additional, Pezzuto, S., additional, Poulin, Y., additional, Schisano, E., additional, and Schuller, F., additional

Published
2021
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15. H II regions and high-mass starless clump candidates

Author

Zhang, S., primary, Zavagno, A., additional, López-Sepulcre, A., additional, Liu, H., additional, Louvet, F., additional, Figueira, M., additional, Russeil, D., additional, Wu, Y., additional, Yuan, J., additional, and Pillai, T. G. S., additional

Published
2021
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18. The role of Galactic H II regions in the formation of filaments

Author

Zavagno, A., primary, André, Ph., additional, Schuller, F., additional, Peretto, N., additional, Shimajiri, Y., additional, Arzoumanian, D., additional, Csengeri, T., additional, Figueira, M., additional, Fuller, G. A., additional, Könyves, V., additional, Men’shchikov, A., additional, Palmeirim, P., additional, Roussel, H., additional, Russeil, D., additional, Schneider, N., additional, and Zhang, S., additional

Published
2020
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20. A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE)

Author

Stephen Gwyn, Annie Zavagno, Patrick R. Durrell, Médéric Boquien, Ming Sun, P. Côté, Baerbel Koribalski, Luca Cortese, E. Toloba, Matteo Fossati, Alessandro Boselli, Bernd Vollmer, Gerhard Hensler, Joel Roediger, Giuseppe Gavazzi, Stephanie Cote, V. Buat, Denis Burgarella, Jean-Charles Cuillandre, D. Russeil, Michele Fumagalli, G. Consolandi, Laura Ferrarese, Yannick Roehlly, Samuel Boissier, Boselli, A, Fossati, M, Cuillandre, J, Boissier, S, Boquien, M, Buat, V, Burgarella, D, Consolandi, G, Cortese, L, Cote, P, Cote, S, Durrell, P, Ferrarese, L, Fumagalli, M, Gavazzi, G, Gwyn, S, Hensler, G, Koribalski, B, Roediger, J, Roehlly, Y, Russeil, D, Sun, M, Toloba, E, Vollmer, B, Zavagno, A, 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), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), Bordeaux population health (BPH), Université de Bordeaux (UB)-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale (INSERM), Shanghai Maritime University, Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universitätssternwarte der Ludwig-Maximiliansuniversität, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Unidad de Astronomia, Facultad de Ciencias Basicas, Universidad de Antofagasta, Milano, International Centre for Radio Astronomy Research, University of Western Australia (ICRAR), National Research Council of Canada (NRC), Department of Physics and Astronomy, Youngstown State University, Institute for Computational Cosmology, Department of Physics, Durham University, Durham (ICC), Department of Astrophysics, University of Vienna, Turkenschanzstrasse 17, 1180, Vienna, Austria, Australian Telescope National Facility (ATNF), Astronomy Centre, Department of Physics and Astronomy, University of Sussex, Falmer, CSPAR and Physics Department, University of Alabama in Huntsville, Huntsville, Department of Physiscs, University of the Pacific, 3601 Pacific Avenue, Stockton, CA, 95211, USA, Observatoire astronomique de Strasbourg (OAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-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), Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), CDS, Centre de Données astronomiques de Strasbourg, Observatoire astronomique de Strasbourg, France + ESO, European Southern Observatory, Garching bei Muenchen, Allemagne, Université de Strasbourg (UNISTRA)-Université Louis Pasteur - Strasbourg I, 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
[SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, [SCCO]Cognitive science, Intracluster medium, 0103 physical sciences, Galaxy formation and evolution, galaxies: interactions, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Galaxies: individual: NGC 4254, Astrophysics::Galaxy Astrophysics, Physics, Spiral galaxy, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Star formation, Galaxies: evolution, Astronomy and Astrophysics, Galaxies: clusters: individual: Virgo, Virgo Cluster, Astrophysics - Astrophysics of Galaxies, Galaxy, Ram pressure, Galaxies: ISM, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, Galaxies: interaction, Astrophysics of Galaxies (astro-ph.GA), Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics, Galaxies: clusters: general, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

During pilot observations of the Virgo Environmental Survey Tracing Galaxy Evolution (VESTIGE), a blind narrow-band Halpha+[NII] imaging survey of the Virgo cluster carried out with MegaCam at the CFHT, we have observed the spiral galaxy NGC 4254 (M99). Deep Halpha+[NII] narrow-band and GALEX UV images revealed the presence of 60 compact (70-500 pc radius) star forming regions up to ~ 20 kpc outside the optical disc of the galaxy. These regions are located along a tail of HI gas stripped from the disc of the galaxy after a rapid gravitational encounter with another Virgo cluster member that simulations indicate occurred 280-750 Myr ago. We have combined the VESTIGE data with multifrequency data from the UV to the far-infrared to characterise the stellar populations of these regions and study the star formation process in an extreme environment such as the tails of stripped gas embedded in the hot intracluster medium. The colour, spectral energy distribution (SED), and linear size consistently indicate that these regions are coeval and have been formed after a single burst of star formation that occurred ~< 100 Myr ago. These regions might become free floating objects within the cluster potential well, and be the local analogues of compact sources produced after the interaction of gas-rich systems that occurred during the early formation of clusters., Accepted for publication on Astronomy & Astrophysics

Published
2018
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21. Multiwavelength study of the G345.5+1.5 region

Author

Leonardo Bronfman, N. U. Duronea, Cristian Lopez-Calderon, Annie Zavagno, L. A. Nyman, C. Hervías-Caimapo, M. Figueira, 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), National Centre for Nuclear Research [Otwock], Narodowe Centrum Badań Jądrowych (NCBJ), 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
HII regions, Infrared, Ciencias Físicas, Population, FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, Virial theorem, Stellar formation, purl.org/becyt/ford/1 [https], 0103 physical sciences, education, 010303 astronomy & astrophysics, ISM, Physics, education.field_of_study, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Star formation, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], Galactic plane, Astrophysics - Astrophysics of Galaxies, Astronomía, Stars, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Spectral energy distribution, CIENCIAS NATURALES Y EXACTAS
Abstract

Star-forming regions are usually studied in the context of Galactic surveys, but dedicated observations are sometimes needed when the study reaches beyond the survey area. Here, we studied the G345.5+1.5 region, which is located slightly above the Galactic plane, to understand its star formation properties. We combined the LABOCA and $^{12}$CO(4$-$3) transition line observations complemented with the Hi-GAL and $\it{Spitzer}$-GLIMPSE surveys to study the star formation toward this region. We used the Clumpfind algorithm to extract the clumps from the 870$\mu$m and $^{12}$CO(4$-$3) data. Radio emission at 36cm was used to estimate the number of HII regions and to remove the contamination from the free-free emission at 870$\mu$m. We employed color-color diagrams and spectral energy distribution slopes to distinguish between prestellar and protostellar clumps. We studied the boundedness of the clumps through the virial parameter. Finally, we estimated the star formation efficiency and star formation rate of the region and used the Schmidt-Kennicutt diagram to compare its ability to form stars. Of the 13 radio sources that we found using the MGPS-2 catalog, 7 are found to be associated with HII regions corresponding to late-B or early-O stars. We found 45 870$\mu$m clumps, and 107 $^{12}$CO clumps. More than 50\% of the clumps are protostellar and bounded and are able to host star formation. High SFR and SFR density values are associated with the region, with an SFE of a few percent. With submillimeter, CO transition, and short-wavelength infrared observations, our study reveals a population of massive stars, protostellar and bound starless clumps, toward G345.5+1.5. This region is therefore actively forming stars, and its location in the starburst quadrant of the Schmidt-Kennicutt diagram is comparable to other star-forming regions found within the Galactic plane., Comment: 20 pages - 15 figures

Published
2019
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22. Herschel-HOBYS study of the earliest phases of high-mass star formation in NGC 6357★,★★

Author

Russeil, D., Figueira, M., Zavagno, A., Motte, F., Schneider, N., Men'shchikov, A., Bontemps, S., Andre, P., Anderson, L.D., Benedettini, M., Konyves, Vera, Russeil, D., Figueira, M., Zavagno, A., Motte, F., Schneider, N., Men'shchikov, A., Bontemps, S., Andre, P., Anderson, L.D., Benedettini, M., and Konyves, Vera

Abstract

Aims. To constrain models of high-mass star formation it is important to identify the massive dense cores (MDCs) that are able to form high-mass star(s). This is one of the purposes of the Herschel/HOBYS key programme. Here, we carry out the census and characterise of the properties of the MDCs population of the NGC 6357 H II region. Methods. Our study is based on the Herschel/PACS and SPIRE 70−500 μm images of NGC 6357 complemented with (sub-)millimetre and mid-infrared data. We followed the procedure established by the Herschel/HOBYS consortium to extract ~0.1 pc massive dense cores using the getsources software. We estimated their physical parameters (temperatures, masses, luminosities) from spectral energy distribution (SED) fitting. Results. We obtain a complete census of 23 massive dense cores, amongst which one is found to be IR-quiet and twelve are starless, representing very early stages of the star-formation process. Focussing on the starless MDCs, we have considered their evolutionary status, and suggest that only five of them are likely to form a high-mass star. Conclusions. We find that, contrarily to the case in NGC 6334, the NGC 6357 region does not exhibit any ridge or hub features that are believed to be crucial to the massive star formation process. This study adds support for an empirical model in which massive dense cores and protostars simultaneously accrete mass from the surrounding filaments. In addition, the massive star formation in NGC 6357 seems to have stopped and the hottest stars in Pismis 24 have disrupted the filaments.

Published
2019

24. Herschel-HOBYS study of the earliest phases of high-mass star formation in NGC 6357

Author

Russeil, D., primary, Figueira, M., additional, Zavagno, A., additional, Motte, F., additional, Schneider, N., additional, Men’shchikov, A., additional, Bontemps, S., additional, André, P., additional, Anderson, L. D., additional, Benedettini, M., additional, Didelon, P., additional, Di Francesco, J., additional, Elia, D., additional, Könyves, V., additional, Nguyen Luong, Q., additional, Nony, T., additional, Pezzuto, S., additional, Rygl, K. L. J., additional, Schisano, E., additional, Spinoglio, L., additional, Tigé, J., additional, and White, G. J., additional

Published
2019
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27. The spatial distribution of star formation related to ionized regions throughout the Inner Galactic Plane

Author

Palmeirim, P, Zavagno, A, Elia, D, Moore, TJT, Whitworth, A, Tremblin, P, Traficante, A, Merello, M, Russeil, D, Pezzuto, S, Cambresy, L, Baldeschi, A, Bandiermonte, M, Becciani, U, Benedettini, M, Buemi, C, Bufano, F, Bulpitt, A, Butora, R, Carey, D, Costa, A, Deharveng, L, Di Girogio, A, Eden, D, Hajnal, A, Hoare, M, Kacsuk, P, Leto, P, Marsh, K, Mege, P, Molinari, M, Molinaro, M, Noriega-Crespo, A, Schisano, E, Sciacca, E, Trigilio, C, Umana, G, and Vitello, F

Subjects
Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

We present a comprehensive statistical analysis of star-forming objects located in the vicinities of 1 360 bubble structures throughout the Galactic Plane and their local environments. The compilation of ∼70 000 star-forming sources, found in the proximity of the ionized (Hii) regions, detected in both Hi-GAL and GLIMPSE surveys, provided a broad overview of the different evolutionary stages of star-formation in bubbles, from prestellar objects to more evolved Young Stellar Objects (YSOs). Surface density maps of star-forming objects clearly reveal an evolutionary trend where more evolved star-forming objects (Class II YSO candidates) are found spatially located near the center, while younger star-forming objects are found at the edge of the bubbles. We derived dynamic ages for a sub-sample of 182 H ii regions for which kinematic distances and radio continuum flux measurements were available. We detect approximately 80% more star-forming sources per unit area in the direction of bubbles compared with the surrounding fields. We estimate the Clump Formation Efficiency (CFE) of Hi-GAL clumps in the direction of the shell of the bubbles to be ∼ 10%, around twice the value of the CFE in fields not affected by feedback effects. We find that the higher values of CFE is mostly due to the higher CFE of protostellar clumps, in particular in younger bubbles for which the density of the bubble shells is higher. We argue that the formation rate from prestellar to protostellar phase is probably higher during the early stages of the (H ii ) bubble expansion. Furthermore, we also find a higher fraction of massive YSOs (MYSOs) in bubbles at the early stages of expansion (< 2 Myr) than older bubbles. Evaluation of the fragmentation time inside the shell of bubbles advocate for the pre-existence of clumps in the medium prior to the bubble expansion in order to explain the formation of MYSOs in the youngest H ii regions (< 1 Myr), as supported by numerical simulations. Approximately 23% of Hi-GAL clumps are found located in the direction of a bubble, with 15% for prestellar clumps and 41% for protostellar clumps. We argue that the high fraction of protostellar clumps may be due to the acceleration of the star-formation process cause by the feedback of the (H ii ) bubbles.

Published
2017

28. Bipolar H II regions

Author

Samal, M. R., primary, Deharveng, L., additional, Zavagno, A., additional, Anderson, L. D., additional, Molinari, S., additional, and Russeil, D., additional

Published
2018
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30. A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE)

Author

Boselli, A., primary, Fossati, M., additional, Cuillandre, J. C., additional, Boissier, S., additional, Boquien, M., additional, Buat, V., additional, Burgarella, D., additional, Consolandi, G., additional, Cortese, L., additional, Côté, P., additional, Côté, S., additional, Durrell, P., additional, Ferrarese, L., additional, Fumagalli, M., additional, Gavazzi, G., additional, Gwyn, S., additional, Hensler, G., additional, Koribalski, B., additional, Roediger, J., additional, Roehlly, Y., additional, Russeil, D., additional, Sun, M., additional, Toloba, E., additional, Vollmer, B., additional, and Zavagno, A., additional

Published
2018
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31. Hi-GAL, the Herschel infrared Galactic Plane Survey: Photometric maps and compact source catalogues: First data release for the inner Milky Way: +68° ≥ l ≥ -70°

Author

Stefano Pezzuto, Annie Zavagno, M. J. Barlow, Nicolas Peretto, S. D. Lord, Yasuo Fukui, Davide Elia, G. Polenta, D. Russeil, Sergio Molinari, Thomas P. Robitaille, R. Del Grande, G. Umana, Riccardo Cesaroni, M. Benedettini, Pascal André, Benjamin L. Schulz, Babar Ali, Pierrick Martin, David Eden, P. Natoli, Göran Pilbratt, Manuel Merello, R. Paladini, Francesco Strafella, Alessio Traficante, Luca Calzoletti, Mathieu Compiegne, Derek Ward-Thompson, Peter Schilke, Gilles Joncas, Rene Plume, Nicola Schneider, Pedro García-Lario, J.-P. Bernard, Kazi L.J. Rygl, Leonardo Testi, M. T. Beltrán, M. R. Pestalozzi, F. Piacentini, A. M. di Giorgio, Eugenio Schisano, Christopher M. Brunt, John Bally, N. Billot, Maggie A. Thompson, Sean K. Carey, Joseph C. Mottram, B. M. Swinyard, Melvin Hoare, F. Faustini, S. J. Liu, S. Martinavarro-Armengol, D. Paradis, Toby J. T. Moore, D. Polychroni, Antonella Palmese, Friedrich Wyrowski, Alberto Noriega-Crespo, Lorenzo Piazzo, Tanya Lim, M. Veneziani, Meng-Lin Huang, Bruce Sibthorpe, and Frédérique Motte

Subjects
Physics, Line-of-sight, 010308 nuclear & particles physics, Infrared, Milky Way, Bolometer, Astronomy and Astrophysics, Astrophysics, Galactic plane, dust, extinction, Galaxy: disk, infrared: ISM, methods: data analysis, stars: formation, techniques: photometric, astronomy and astrophysics, space and planetary science, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, law.invention, symbols.namesake, Wavelength, 13. Climate action, Space and Planetary Science, law, 0103 physical sciences, symbols, Spectral energy distribution, Planck, 010303 astronomy & astrophysics, QC, QB
Abstract

(Abridged) We present the first public release of high-quality data products (DR1) from Hi-GAL, the {\em Herschel} infrared Galactic Plane Survey. Hi-GAL is the keystone of a suite of continuum Galactic Plane surveys from the near-IR to the radio, and covers five wavebands at 70, 160, 250, 350 and 500 micron, encompassing the peak of the spectral energy distribution of cold dust for 8 < T < 50K. This first Hi-GAL data release covers the inner Milky Way in the longitude range 68{\deg} > l > -70{\deg} in a |b, Comment: Astronomy & Astrophysics, accepted

Published
2016

32. Hi-GAL, the Herschel infrared Galactic Plane Survey: photometric maps and compact source catalogues First data release for the inner Milky Way:+68 degrees >= l >=-70 degrees

Author

Molinari, S., Schisano, E., Elia, D., Pestalozzi, M., Traficante, A., Pezzuto, S., Swinyard, B. M., Noriega Crespo, A., Bally, J., Moore, T. J. T., Plume, R., Zavagno, A., di Giorgio, A. M., Liu, S. J., Pilbratt, G. L., Mottram, J. C., Russeil, D., Piazzo, L., Veneziani, M., Benedettini, M., Calzoletti, L., Faustini, F., Natoli, Paolo, Piacentini, F., Merello, M., Palmese, A., Del Grande, R., Polychroni, D., Ryg, K. L. J., Polenta, G., Barlow, M. J., Bernard, J. P., Martin, P. G., Testi, L., Ali, B., Andre, P., Beltran, M. T., Billot, N., Carey, S., Cesaroni, R., Compiegne, M., Eden, D., Fukui, Y., Garcia Lario, P., Hoare, M. G., Huang, M., Joncas, G., Lim, T. L., Lord, . D., Martinavarro Armengol, S., Motte, F., Paladini, R., Paradis, D., Peretto, N., Robitaille, T., Schilke, P., Schneider, N., Schulz, B., Sibthorpe, B., Strafella, F., Thompson, M. A., Umana, G., Ward Thompson, D., and Wyrowski, F.

Subjects
infrared: ISM, techniques: photometric, stars: formation, extinction, dust, extinction, infrared: ISM, stars: formation, Galaxy: disk, methods: data analysis , techniques: photometric, dust, methods: data analysis, NO, Galaxy: disk, QB
Abstract

Aims. We present the first public release of high-quality data products (DR1) from Hi-GAL, the Herschel infrared Galactic Plane Survey. Hi-GAL is the keystone of a suite of continuum Galactic plane surveys from the near-IR to the radio and covers five wavebands at 70, 160, 250, 350 and 500 μm, encompassing the peak of the spectral energy distribution of cold dust for 8 ≲ T ≲ 50 K. This first Hi-GAL data release covers the inner Milky Way in the longitude range 68° ≳ ℓ ≳ −70° in a | b | ≤ 1° latitude strip.\ud Methods. Photometric maps have been produced with the ROMAGAL pipeline, which optimally capitalizes on the excellent sensitivity and stability of the bolometer arrays of the Herschel PACS and SPIRE photometric cameras. It delivers images of exquisite quality and dynamical range, absolutely calibrated with Planck and IRAS, and recovers extended emission at all wavelengths and all spatial scales, from the point-spread function to the size of an entire 2°× 2° “tile” that is the unit observing block of the survey. The compact source catalogues were generated with the CuTEx algorithm, which was specifically developed to optimise source detection and extraction in the extreme conditions of intense and spatially varying background that are found in the Galactic plane in the thermal infrared.\ud Results. Hi-GAL DR1 images are cirrus noise limited and reach the 1σ-rms predicted by the Herschel Time Estimators for parallel-mode observations at 60′′ s-1 scanning speed in relatively low cirrus emission regions. Hi-GAL DR1 images will be accessible through a dedicated web-based image cutout service. The DR1 Compact Source Catalogues are delivered as single-band photometric lists containing, in addition to source position, peak, and integrated flux and source sizes, a variety of parameters useful to assess the quality and reliability of the extracted sources. Caveats and hints to help in this assessment are provided. Flux completeness limits in all bands are determined from extensive synthetic source experiments and greatly depend on the specific line of sight along the Galactic plane because the background strongly varies as a function of Galactic longitude. Hi-GAL DR1 catalogues contain 123210, 308509, 280685, 160972, and 85460 compact sources in the five bands.

Published
2016

33. ATLASGAL – The APEX telescope large area survey of the galaxy at 870 $\mathsf{\mu}$m

Author

Thomas Henning, Peter Schilke, Bertrand Lefloch, Ernst Kreysa, Christophe Risacher, Diego Mardones, V. Revéret, Hendrik Linz, Achim Weiss, L. Deharveng, Giorgio Siringo, Frédérique Motte, D. Russeil, Sergio Molinari, Henrik Beuther, Leonardo Testi, Leonardo Bronfman, Friedrich Wyrowski, M. Wienen, R. Cesaroni, Annie Zavagno, Fabrice Herpin, Guido Garay, Attila Kovács, Karl M. Menten, Sylvain Bontemps, Frederic Schuller, T. Vasyunina, Yanett Contreras, Vincent Minier, C. M. Walmsley, T. Troost, L. A. Nyman, and Nicola Schneider

Subjects
Physics, 010504 meteorology & atmospheric sciences, Star formation, Milky Way, Extinction (astronomy), Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Galactic plane, 01 natural sciences, Galaxy, Interstellar medium, Star cluster, Space and Planetary Science, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Protostar, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences
Abstract

(Abridged) Studying continuum emission from interstellar dust is essential to locate and characterize the highest density regions in the interstellar medium. In particular, the early stages of massive star formation are still mysterious. Our goal is to produce a large scale, systematic database of massive pre- and proto-stellar clumps in the Galaxy, in order to better understand how and under what conditions star formation takes place. A well characterized sample of star-forming sites will deliver an evolutionary sequence and a mass function of high-mass star-forming clumps. Such a systematic survey at submm wavelengths also represents a pioneering work in preparation for Herschel and ALMA. The APEX telescope is ideally located to observe the inner Milky Way. The recently commissioned Large APEX Bolometer Camera (LABOCA) is a 295-element bolometer array observing at 870 microns, with a beam of 19". Taking advantage of its large field of view (11.4') and excellent sensitivity, we have started an unbiased survey of the Galactic Plane, with a noise level of 50-70 mJy/beam: the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL). As a first step, we have covered 95 sq. deg. These data reveal 6000 compact sources brighter than 0.25 Jy, as well as extended structures, many of them filamentary. About two thirds of the compact sources have no bright infrared counterpart, and some of them are likely to correspond to the precursors of (high-mass) proto-stars or proto-clusters. Other compact sources harbor hot cores, compact HII regions or young embedded clusters. Assuming a typical distance of 5 kpc, most sources are clumps smaller than 1 pc with masses from a few 10 to a few 100 M_sun. In this introductory paper, we show preliminary results from these ongoing observations, and discuss the perspectives of the survey.

Published
2009
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34. NGC 6334 and NGC 6357

Author

Russeil, D., primary, Adami, C., additional, Bouret, J. C., additional, Hervé, A., additional, Parker, Q. A., additional, Zavagno, A., additional, and Motte, F., additional

Published
2017
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35. Spatial distribution of star formation related to ionized regions throughout the inner Galactic plane

Author

Palmeirim, P., primary, Zavagno, A., additional, Elia, D., additional, Moore, T. J. T., additional, Whitworth, A., additional, Tremblin, P., additional, Traficante, A., additional, Merello, M., additional, Russeil, D., additional, Pezzuto, S., additional, Cambrésy, L., additional, Baldeschi, A., additional, Bandieramonte, M., additional, Becciani, U., additional, Benedettini, M., additional, Buemi, C., additional, Bufano, F., additional, Bulpitt, A., additional, Butora, R., additional, Carey, D., additional, Costa, A., additional, Deharveng, L., additional, Di Giorgio, A., additional, Eden, D., additional, Hajnal, A., additional, Hoare, M., additional, Kacsuk, P., additional, Leto, P., additional, Marsh, K., additional, Mège, P., additional, Molinari, S., additional, Molinaro, M., additional, Noriega-Crespo, A., additional, Schisano, E., additional, Sciacca, E., additional, Trigilio, C., additional, Umana, G., additional, and Vitello, F., additional

Published
2017
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36. The earliest phases of high-mass star formation, as seen in NGC 6334 by Herschel-HOBYS

Author

Tigé, J., primary, Motte, F., additional, Russeil, D., additional, Zavagno, A., additional, Hennemann, M., additional, Schneider, N., additional, Hill, T., additional, Nguyen Luong, Q., additional, Di Francesco, J., additional, Bontemps, S., additional, Louvet, F., additional, Didelon, P., additional, Könyves, V., additional, André, Ph., additional, Leuleu, G., additional, Bardagi, J., additional, Anderson, L. D., additional, Arzoumanian, D., additional, Benedettini, M., additional, Bernard, J.-P., additional, Elia, D., additional, Figueira, M., additional, Kirk, J., additional, Martin, P. G., additional, Minier, V., additional, Molinari, S., additional, Nony, T., additional, Persi, P., additional, Pezzuto, S., additional, Polychroni, D., additional, Rayner, T., additional, Rivera-Ingraham, A., additional, Roussel, H., additional, Rygl, K., additional, Spinoglio, L., additional, and White, G. J., additional

Published
2017
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37. Herschelobservations of the Galactic H ii region RCW 79

Author

Liu, Hong-Li, primary, Figueira, Miguel, additional, Zavagno, Annie, additional, Hill, Tracey, additional, Schneider, Nicola, additional, Men’shchikov, Alexander, additional, Russeil, Delphine, additional, Motte, Frédérique, additional, Tigé, Jérémy, additional, Deharveng, Lise, additional, Anderson, Loren D., additional, Li, Jin-Zeng, additional, Wu, Yuefang, additional, Yuan, Jing-Hua, additional, and Huang, Maohai, additional

Published
2017
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38. SEDIGISM: Structure, excitation, and dynamics of the inner Galactic interstellar medium

Author

Schuller, F., primary, Csengeri, T., additional, Urquhart, J. S., additional, Duarte-Cabral, A., additional, Barnes, P. J., additional, Giannetti, A., additional, Hernandez, A. K., additional, Leurini, S., additional, Mattern, M., additional, Medina, S.-N. X., additional, Agurto, C., additional, Azagra, F., additional, Anderson, L. D., additional, Beltrán, M. T., additional, Beuther, H., additional, Bontemps, S., additional, Bronfman, L., additional, Dobbs, C. L., additional, Dumke, M., additional, Finger, R., additional, Ginsburg, A., additional, Gonzalez, E., additional, Henning, T., additional, Kauffmann, J., additional, Mac-Auliffe, F., additional, Menten, K. M., additional, Montenegro-Montes, F. M., additional, Moore, T. J. T., additional, Muller, E., additional, Parra, R., additional, Perez-Beaupuits, J.-P., additional, Pettitt, A., additional, Russeil, D., additional, Sánchez-Monge, Á., additional, Schilke, P., additional, Schisano, E., additional, Suri, S., additional, Testi, L., additional, Torstensson, K., additional, Venegas, P., additional, Wang, K., additional, Wienen, M., additional, Wyrowski, F., additional, and Zavagno, A., additional

Published
2017
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40. Star formation towards the Galactic H II region RCW 120

Author

Figueira, M., primary, Zavagno, A., additional, Deharveng, L., additional, Russeil, D., additional, Anderson, L. D., additional, Men’shchikov, A., additional, Schneider, N., additional, Hill, T., additional, Motte, F., additional, Mège, P., additional, LeLeu, G., additional, Roussel, H., additional, Bernard, J.-P., additional, Traficante, A., additional, Paradis, D., additional, Tigé, J., additional, André, P., additional, Bontemps, S., additional, and Abergel, A., additional

Published
2017
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41. From forced collapse to H ii region expansion in Mon R2: Envelope density structure and age determination with Herschel

Author

Frédérique Motte, D. Ward-Thompson, Annie Zavagno, D. Russeil, Marc Sauvage, Pierre Didelon, M. Hennemann, J. Di Francesco, Thomas Rayner, L. D. Anderson, A. Rivera-Ingraham, F. Louvet, Glenn J. White, Doris Arzoumanian, Sacha Hony, Alexander Men'shchikov, Ph. André, Frédéric Galliano, Nicolas Peretto, J.-P. Bernard, Tracey Hill, Pascal Tremblin, Vianney Lebouteiller, Vera Könyves, P. Palmeirim, Q. Nguyen Luong, M. Benedettini, K. L. J. Rygl, Stefano Pezzuto, Vincent Minier, M. González, Patrick Hennebelle, Matthew James Griffin, Sylvain Bontemps, Nicola Schneider, 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), University of Exeter, 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), Joint ALMA Office, 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, National Radio Astronomy Observatory (NRAO), 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), School of Physics and Astronomy [Cardiff], Cardiff University, European Space Research and Technology Centre (ESTEC), Agence Spatiale Européenne = European Space Agency (ESA), 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), 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), 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), Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), National Research Council of Canada (NRC), Institut de recherche en astrophysique et planétologie (IRAP), Jeremiah Horrocks Institute for Mathematics, Physics and Astronomy [Preston], University of Central Lancashire [Preston] (UCLAN), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), ANR-08-BLAN-0241,PROBES,Etoiles Proto-OB : recherche systématique dans notre Galaxie des cibles pour ALMA(2008), 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)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Paris-Sud - Paris 11 (UP11)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Space Agency (ESA), 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 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), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-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, Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Ionization, H II region, ISM: individual objects: Mon R2, Numerical models, ISM: structure, Extinction (astronomy), FOS: Physical sciences, Collapse (topology), F500, Astrophysics, Isothermal process, Stars: protostars, Clouds, Quenching, H II regions, Solar and Stellar Astrophysics (astro-ph.SR), Envelope (waves), QB, Physics, Dust , extinction, Molecular cloud, Astronomy and Astrophysics, Stars, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Density of gases
Abstract

The surroundings of HII regions can have a profound influence on their development, morphology, and evolution. This paper explores the effect of the environment on H II regions in the MonR2 molecular cloud. We aim to investigate the density structure of envelopes surrounding HII regions and to determine their collapse and ionisation expansion ages. The Mon R2 molecular cloud is an ideal target since it hosts an H II region association. Column density and temperature images derived from Herschel data were used together to model the structure of HII bubbles and their surrounding envelopes. The resulting observational constraints were used to follow the development of the Mon R2 ionised regions with analytical calculations and numerical simulations. The four hot bubbles associated with H II regions are surrounded by dense, cold, and neutral gas envelopes. The radial density profiles are reminiscent of those of low-mass protostellar envelopes. The inner parts of envelopes of all four HII regions could be free-falling because they display shallow density profiles. As for their outer parts, the two compact HII regions show a density profile, which is typical of the equilibrium structure of an isothermal sphere. In contrast, the central UCHii region shows a steeper outer profile, that could be interpreted as material being forced to collapse. The size of the heated bubbles, the spectral type of the irradiating stars, and the mean initial neutral gas density are used to estimate the ionisation expansion time, texp, 0.1Myr,for the dense UCHII and compact HII regions and 0.35 Myr for the extended HII region. The envelope transition radii between the shallow and steeper density profiles are used to estimate the time elapsed since the formation of the first proto stellar embryo, Tinf : 1Myr, for the ultra-compact, 1.5 / 3Myr for the compact, and greater than 6Myr for the extended HII regions., 25pages A&A sous presse

Published
2015
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42. Hi-GAL, theHerschelinfrared Galactic Plane Survey: photometric maps and compact source catalogues

Author

Molinari, S., Schisano, E., Elia, D., Pestalozzi, M., Traficante, A., Pezzuto, S., Swinyard, B. M., Noriega-Crespo, A., Bally, J., Moore, T. J. T., Plume, R., Zavagno, A., di Giorgio, A. M., Liu, S. J., Pilbratt, G. L., Mottram, J. C., Russeil, D., Piazzo, L., Veneziani, M., Benedettini, M., Calzoletti, L., Faustini, F., Natoli, P., Piacentini, F., Merello, M., Palmese, A., Del Grande, R., Polychroni, D., Rygl, K. L. J., Polenta, G., Barlow, M. J., Bernard, J.-P., Martin, P. G., Testi, L., Ali, B., André, P., Beltrán, M. T., Billot, N., Carey, S., Cesaroni, R., Compiègne, M., Eden, D., Fukui, Y., Garcia-Lario, P., Hoare, M. G., Huang, M., Joncas, G., Lim, T. L., Lord, S. D., Martinavarro-Armengol, S., Motte, F., Paladini, R., Paradis, D., Peretto, N., Robitaille, T., Schilke, P., Schneider, N., Schulz, B., Sibthorpe, B., Strafella, F., Thompson, M. A., Umana, G., Ward-Thompson, Derek, Wyrowski, F., Molinari, S., Schisano, E., Elia, D., Pestalozzi, M., Traficante, A., Pezzuto, S., Swinyard, B. M., Noriega-Crespo, A., Bally, J., Moore, T. J. T., Plume, R., Zavagno, A., di Giorgio, A. M., Liu, S. J., Pilbratt, G. L., Mottram, J. C., Russeil, D., Piazzo, L., Veneziani, M., Benedettini, M., Calzoletti, L., Faustini, F., Natoli, P., Piacentini, F., Merello, M., Palmese, A., Del Grande, R., Polychroni, D., Rygl, K. L. J., Polenta, G., Barlow, M. J., Bernard, J.-P., Martin, P. G., Testi, L., Ali, B., André, P., Beltrán, M. T., Billot, N., Carey, S., Cesaroni, R., Compiègne, M., Eden, D., Fukui, Y., Garcia-Lario, P., Hoare, M. G., Huang, M., Joncas, G., Lim, T. L., Lord, S. D., Martinavarro-Armengol, S., Motte, F., Paladini, R., Paradis, D., Peretto, N., Robitaille, T., Schilke, P., Schneider, N., Schulz, B., Sibthorpe, B., Strafella, F., Thompson, M. A., Umana, G., Ward-Thompson, Derek, and Wyrowski, F.

Abstract

Aims. We present the first public release of high-quality data products (DR1) from Hi-GAL, the Herschel infrared Galactic Plane Survey. Hi-GAL is the keystone of a suite of continuum Galactic plane surveys from the near-IR to the radio and covers five wavebands at 70, 160, 250, 350 and 500 µm, encompassing the peak of the spectral energy distribution of cold dust for 8 < T < 50 K. This first Hi-GAL data release covers the inner Milky Way in the longitude range 68◦ > t > −70◦ in a |b| ≤ 1◦ latitude strip. ∼ ∼ ∼ ∼ Methods. Photometric maps have been produced with the ROMAGAL pipeline, which optimally capitalizes on the excellent sensitivity and stability of the bolometer arrays of the Herschel PACS and SPIRE photometric cameras. It delivers images of exquisite quality and dynamical range, absolutely calibrated with Planck and IRAS, and recovers extended emission at all wavelengths and all spatial scales, from the point-spread function to the size of an entire 2◦ × 2◦ “tile” that is the unit observing block of the survey. The compact source catalogues were generated with the CuTEx algorithm, which was specifically developed to optimise source detection and extraction in the extreme conditions of intense and spatially varying background that are found in the Galactic plane in the thermal infrared. Results. Hi-GAL DR1 images are cirrus noise limited and reach the 1σ-rms predicted by the Herschel Time Estimators for parallel-mode obser- vations at 6011 s−1 scanning speed in relatively low cirrus emission regions. Hi-GAL DR1 images will be accessible through a dedicated web-based image cutout service. The DR1 Compact Source Catalogues are delivered as single-band photometric lists containing, in addition to source posi- tion, peak, and integrated flux and source sizes, a variety of parameters useful to assess the quality and reliability of the extracted sources. Caveats and hints to help in this assessment are provided. Flux completeness limits in all bands are determined

Published
2016

43. ATLASGAL-selected massive clumps in the inner Galaxy: II. Characterisation of different evolutionary stages and their SiO emission

Author

Csengeri, T., Leurini, S., Wyrowski, F., Urquhart, J.S., Menten, K.M., Walmsley, M., Bontemps, S., Wienen, M., Beuther, H., Motte, F., Nguyen-Luong, Q., Schilke, P., Schuller, F., Zavagno, A., Sanna, C., Csengeri, T., Leurini, S., Wyrowski, F., Urquhart, J.S., Menten, K.M., Walmsley, M., Bontemps, S., Wienen, M., Beuther, H., Motte, F., Nguyen-Luong, Q., Schilke, P., Schuller, F., Zavagno, A., and Sanna, C.

Abstract

Context. The processes leading to the birth of high-mass stars are poorly understood. The key first step to reveal their formation processes is characterising the clumps and cores from which they form. Aims. We define a representative sample of massive clumps in different evolutionary stages selected from the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL), from which we aim to establish a census of molecular tracers of their evolution. As a first step, we study the shock tracer, SiO, mainly associated with shocks from jets probing accretion processes. In low-mass young stellar objects (YSOs), outflow and jet activity decreases with time during the star formation processes. Recently, a similar scenario was suggested for massive clumps based on SiO observations. Here we analyse observations of the SiO (2?1) and (5?4) lines in a statistically significant sample to constrain the change of SiO abundance and the excitation conditions as a function of evolutionary stage of massive star-forming clumps. Methods. We performed an unbiased spectral line survey covering the 3-mm atmospheric window between 84?117 GHz with the IRAM 30 m telescope of a sample of 430 sources of the ATLASGAL survey, covering various evolutionary stages of massive clumps. A smaller sample of 128 clumps has been observed in the SiO (5?4) transition with the APEX telescope to complement the (2?1) line and probe the excitation conditions of the emitting gas. We derived detection rates to assess the star formation activity of the sample, and we estimated the column density and abundance using both an LTE approximation and non-LTE calculations for a smaller subsample, where both transitions have been observed. Results. We characterise the physical properties of the selected sources, which greatly supersedes the largest samples studied so far, and show that they are representative of different evolutionary stages. We report a high detection rate of >75% of the SiO (2?1) line and a >90% detection

Published
2016

44. Ionization compression impact on dense gas distribution and star formation, Probability density functions around H ii regions as seen by Herschel

Author

Nicolas Peretto, J. Di Francesco, T. Giannini, Vincent Minier, Timea Csengeri, A. Rivera-Ingraham, A. P. Marston, Pascal Tremblin, Q. Nguyen Luong, P. Didelon, L. D. Anderson, T. Hill, Annie Zavagno, Nicola Schneider, Doris Arzoumanian, Frédérique Motte, Sylvain Bontemps, Milena Benedettini, Kazi L.J. Rygl, D. Russeil, L. Spinoglio, Martin Hennemann, Glenn J. White, Ph. André, Edouard Audit, FORMATION STELLAIRE 2014, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), 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), 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), Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), foreign laboratories (FL), CERN [Genève], 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), Antarctic Research a European Network for Astrophysics (ARENA), Engineering Department, University of Cambridge [UK] (CAM), 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), 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 ), 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), 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), and 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)

Subjects
Equation of state, H II region, Initial mass function, ISM: structure, Stars: formation, FOS: Physical sciences, Probability density function, Context (language use), Different effects, Astrophysics, Flattening, Ionization of gases, Clouds, Impact ionization, H II regions, QC, Astrophysics::Galaxy Astrophysics, QB, Physics, Star formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Molecular cloud, Equations of state, Log-normal distribution, Methods:observational, Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Stars, Compression zones, Astrophysics - Astrophysics of Galaxies, Probability distributions, 13. Climate action, Space and Planetary Science, C (programming language), Astrophysics of Galaxies (astro-ph.GA), Gases, Distribution functions
Abstract

Ionization feedback should impact the probability distribution function (PDF) of the column density around the ionized gas. We aim to quantify this effect and discuss its potential link to the Core and Initial Mass Function (CMF/IMF). We used in a systematic way Herschel column density maps of several regions observed within the HOBYS key program: M16, the Rosette and Vela C molecular cloud, and the RCW 120 H ii region. We fitted the column density PDFs of all clouds with two lognormal distributions, since they present a double-peak or enlarged shape in the PDF. Our interpretation is that the lowest part of the column density distribution describes the turbulent molecular gas while the second peak corresponds to a compression zone induced by the expansion of the ionized gas into the turbulent molecular cloud. The condensations at the edge of the ionized gas have a steep compressed radial profile, sometimes recognizable in the flattening of the power-law tail. This could lead to an unambiguous criterion able to disentangle triggered from pre-existing star formation. In the context of the gravo-turbulent scenario for the origin of the CMF/IMF, the double peaked/enlarged shape of the PDF may impact the formation of objects at both the low-mass and the high-mass end of the CMF/IMF. In particular a broader PDF is required by the gravo-turbulent scenario to fit properly the IMF with a reasonable initial Mach number for the molecular cloud. Since other physical processes (e.g. the equation of state and the variations among the core properties) have already been suggested to broaden the PDF, the relative importance of the different effects remains an open question., Accepted in A&A

Published
2014
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46. Characterizing filaments in regions of high-mass star formation: High-resolution submilimeter imaging of the massive star-forming complex NGC 6334 with ArTéMiS

Author

André, Ph., primary, Revéret, V., additional, Könyves, V., additional, Arzoumanian, D., additional, Tigé, J., additional, Gallais, P., additional, Roussel, H., additional, Le Pennec, J., additional, Rodriguez, L., additional, Doumayrou, E., additional, Dubreuil, D., additional, Lortholary, M., additional, Martignac, J., additional, Talvard, M., additional, Delisle, C., additional, Visticot, F., additional, Dumaye, L., additional, De Breuck, C., additional, Shimajiri, Y., additional, Motte, F., additional, Bontemps, S., additional, Hennemann, M., additional, Zavagno, A., additional, Russeil, D., additional, Schneider, N., additional, Palmeirim, P., additional, Peretto, N., additional, Hill, T., additional, Minier, V., additional, Roy, A., additional, and Rygl, K. L. J., additional

Published
2016
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47. Hi-GAL, theHerschelinfrared Galactic Plane Survey: photometric maps and compact source catalogues

Author

Molinari, S., primary, Schisano, E., additional, Elia, D., additional, Pestalozzi, M., additional, Traficante, A., additional, Pezzuto, S., additional, Swinyard, B. M., additional, Noriega-Crespo, A., additional, Bally, J., additional, Moore, T. J. T., additional, Plume, R., additional, Zavagno, A., additional, di Giorgio, A. M., additional, Liu, S. J., additional, Pilbratt, G. L., additional, Mottram, J. C., additional, Russeil, D., additional, Piazzo, L., additional, Veneziani, M., additional, Benedettini, M., additional, Calzoletti, L., additional, Faustini, F., additional, Natoli, P., additional, Piacentini, F., additional, Merello, M., additional, Palmese, A., additional, Del Grande, R., additional, Polychroni, D., additional, Rygl, K. L. J., additional, Polenta, G., additional, Barlow, M. J., additional, Bernard, J.-P., additional, Martin, P. G., additional, Testi, L., additional, Ali, B., additional, André, P., additional, Beltrán, M. T., additional, Billot, N., additional, Carey, S., additional, Cesaroni, R., additional, Compiègne, M., additional, Eden, D., additional, Fukui, Y., additional, Garcia-Lario, P., additional, Hoare, M. G., additional, Huang, M., additional, Joncas, G., additional, Lim, T. L., additional, Lord, S. D., additional, Martinavarro-Armengol, S., additional, Motte, F., additional, Paladini, R., additional, Paradis, D., additional, Peretto, N., additional, Robitaille, T., additional, Schilke, P., additional, Schneider, N., additional, Schulz, B., additional, Sibthorpe, B., additional, Strafella, F., additional, Thompson, M. A., additional, Umana, G., additional, Ward-Thompson, D., additional, and Wyrowski, F., additional

Published
2016
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48. NGC 6334 and NGC 6357: Hαkinematics and the nature of the H II regions

Author

Russeil, D., primary, Tigé, J., additional, Adami, C., additional, Anderson, L. D., additional, Schneider, N., additional, Zavagno, A., additional, Samal, M. R., additional, Amram, P., additional, Guennou, L., additional, Le Coarer, E., additional, Walsh, A., additional, Longmore, S. N., additional, and Purcell, C., additional

Published
2016
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49. ATLASGAL-selected massive clumps in the inner Galaxy

Author

Csengeri, T., primary, Leurini, S., additional, Wyrowski, F., additional, Urquhart, J. S., additional, Menten, K. M., additional, Walmsley, M., additional, Bontemps, S., additional, Wienen, M., additional, Beuther, H., additional, Motte, F., additional, Nguyen-Luong, Q., additional, Schilke, P., additional, Schuller, F., additional, Zavagno, A., additional, and Sanna, C., additional

Published
2016
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50. From forced collapse to H ii region expansion in Mon R2: Envelope density structure and age determination withHerschel

Author

Didelon, P., Motte, F., Tremblin, P., Hill, T., Hony, S., Hennemann, M., Hennebelle, P., Anderson, L. D., Galliano, F., Schneider, N., Rayner, T., Rygl, K., Louvet, F., Zavagno, A., Könyves, V., Sauvage, M., André, Ph., Bontemps, S., Peretto, N., Griffin, M., González, M., Lebouteiller, V., Arzoumanian, D., Bernard, J.-P., Benedettini, M., Di Francesco, J., Men’shchikov, A., Minier, V., Nguyên Luong, Q., Palmeirim, P., Pezzuto, S., Rivera-Ingraham, A., Russeil, D., Ward-Thompson, Derek, White, G. J., Didelon, P., Motte, F., Tremblin, P., Hill, T., Hony, S., Hennemann, M., Hennebelle, P., Anderson, L. D., Galliano, F., Schneider, N., Rayner, T., Rygl, K., Louvet, F., Zavagno, A., Könyves, V., Sauvage, M., André, Ph., Bontemps, S., Peretto, N., Griffin, M., González, M., Lebouteiller, V., Arzoumanian, D., Bernard, J.-P., Benedettini, M., Di Francesco, J., Men’shchikov, A., Minier, V., Nguyên Luong, Q., Palmeirim, P., Pezzuto, S., Rivera-Ingraham, A., Russeil, D., Ward-Thompson, Derek, and White, G. J.

Abstract

Context. The surroundings of H ii regions can have a profound influence on their development, morphology, and evolution. This paper explores the effect of the environment on H ii regions in the MonR2 molecular cloud. Aims. We aim to investigate the density structure of envelopes surrounding H ii regions and to determine their collapse and ionisation expansion ages. The Mon R2 molecular cloud is an ideal target since it hosts an H ii region association, which has been imaged by the Herschel PACS and SPIRE cameras as part of the HOBYS key programme. Methods. Column density and temperature images derived from Herschel data were used together to model the structure of H ii bubbles and their surrounding envelopes. The resulting observational constraints were used to follow the development of the Mon R2 ionised regions with analytical calculations and numerical simulations. Results. The four hot bubbles associated with H ii regions are surrounded by dense, cold, and neutral gas envelopes, which are partly embedded in filaments. The envelope’s radial density profiles are reminiscent of those of low-mass protostellar envelopes. The inner parts of envelopes of all four H ii regions could be free-falling because they display shallow density profiles: ρ(r) ∝ r− q with . As for their outer parts, the two compact H ii regions show a ρ(r) ∝ r-2 profile, which is typical of the equilibrium structure of a singular isothermal sphere. In contrast, the central UCH ii region shows a steeper outer profile, ρ(r) ∝ r-2.5, that could be interpreted as material being forced to collapse, where an external agent overwhelms the internal pressure support. Conclusions. The size of the heated bubbles, the spectral type of the irradiating stars, and the mean initial neutral gas density are used to estimate the ionisation expansion time, texp ~ 0.1 Myr, for the dense UCH ii and compact H ii regions and ~ 0.35 Myr for the extended H ii region. Numerical simulations with and without gravity show that

Published
2015

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