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617 results on '"Wesson, R"'

101. Warm water vapour in the sooty outflow from a luminous carbon star

Author

Decin, L., Agúndez, M., Barlow, M. J., Daniel, F., Cernicharo, J., Lombaert, R., De Beck, E., Royer, P., Vandenbussche, B., Wesson, R., Polehampton, E. T., Blommaert, J. A. D. L., De Meester, W., Exter, K., Feuchtgruber, H., Gear, W. K., Gomez, H. L., Groenewegen, M. A. T., Guélin, M., Hargrave, P. C., Huygen, R., Imhof, P., Ivison, R. J., Jean, C., Kahane, C., Kerschbaum, F., Leeks, S. J., Lim, T., Matsuura, M., Olofsson, G., Posch, T., Regibo, S., Savini, G., Sibthorpe, B., Swinyard, B. M., Yates, J. A., and Waelkens, C.

Published
2010
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102. MUSE spectroscopy of planetary nebulae with high abundance discrepancies.

Author

García-Rojas, J, Morisset, C, Jones, D, Wesson, R, Boffin, H M J, Monteiro, H, Corradi, R L M, and Rodríguez-Gil, P

Subjects
PLANETARY nebulae, INTEGRAL field spectroscopy, ELECTRON density, HEAVY elements, ELECTRON temperature, COLD regions
Abstract

We present MUSE deep integral-field unit spectroscopy of three planetary nebulae (PNe) with high-abundance discrepancy factors (ADF > 20): NGC 6778, M 1–42, and Hf 2–2. We have constructed flux maps for more than 40 emission lines, and use them to build extinction, electron temperature (T e), electron density (n e), and ionic abundances maps of a number of ionic species. The effects of the contribution of recombination to the auroral [N  ii ] and [O  ii ] lines on T e and the abundance maps of low-ionization species are evaluated using recombination diagnostics. As a result, low T e values and a downward gradient of T e are found toward the inner zones of each PN. Spatially, this nearly coincides with the increase of abundances of heavy elements measured using recombination lines in the inner regions of PNe, and strongly supports the presence of two distinct gas phases: a cold and metal-rich and a warm one with 'normal' metal content. We have simultaneously constructed, for the first time, the ADF maps of O+ and O2+ and found that they centrally peak for all three PNe under study. We show that the main issue when trying to compute realistic abundances from either ORLs or CELs is to estimate the relative contribution of each gas component to the H  i emission, and we present a method to evaluate it. It is also found that, for the studied high-ADF PNe, the amount of oxygen in the cold and warm regions is of the same order. [ABSTRACT FROM AUTHOR]

Published
2022
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106. IGAPS: the merged IPHAS and UVEX optical surveys of the northern Galactic plane⋆

Author

Monguió, M., Greimel, R., Drew, J.E., Barentsen, G., Groot, P.J., Irwin, M.J., Casares, J., Gänsicke, B.T., Carter, P.J., Corral-Santana, J.M., Gentile-Fusillo, N.P., Greiss, S., Haaften, L.M. van, Hollands, M., Jones, D., Kupfer, T., Manser, C.J., Murphy, D.N.A., McLeod, A.F., Oosting, T., Parker, Q.A., Pyrzas, S., Rodríguez-Gil, P., Roestel, J. van, Scaringi, S., Schellart, P., Toloza, O., Vaduvescu, O., Spaandonk, L. van, Verbeek, K., Wright, N.J., Eislöffel, J., Fabregat, J., Harris, A., Morris, R.A.H., Phillipps, S., Raddi, R., Sabin, L., Unruh, Y., Vink, J.S., Wesson, R., Cardwell, A., Burgos, A. de, Cochrane, R.K., Doostmohammadi, S., Mocnik, T., Stoev, H., Suárez-Andrés, L., Tudor, V., Wilson, T.G., Zegmott, T.J., Monguió, M., Greimel, R., Drew, J.E., Barentsen, G., Groot, P.J., Irwin, M.J., Casares, J., Gänsicke, B.T., Carter, P.J., Corral-Santana, J.M., Gentile-Fusillo, N.P., Greiss, S., Haaften, L.M. van, Hollands, M., Jones, D., Kupfer, T., Manser, C.J., Murphy, D.N.A., McLeod, A.F., Oosting, T., Parker, Q.A., Pyrzas, S., Rodríguez-Gil, P., Roestel, J. van, Scaringi, S., Schellart, P., Toloza, O., Vaduvescu, O., Spaandonk, L. van, Verbeek, K., Wright, N.J., Eislöffel, J., Fabregat, J., Harris, A., Morris, R.A.H., Phillipps, S., Raddi, R., Sabin, L., Unruh, Y., Vink, J.S., Wesson, R., Cardwell, A., Burgos, A. de, Cochrane, R.K., Doostmohammadi, S., Mocnik, T., Stoev, H., Suárez-Andrés, L., Tudor, V., Wilson, T.G., and Zegmott, T.J.

Abstract

Contains fulltext : 219287.pdf (publisher's version ) (Open Access)

Published
2020

107. The dust content of the Crab Nebula

Author

De Looze, I, primary, Barlow, M J, primary, Bandiera, R, primary, Bevan, A, primary, Bietenholz, M F, primary, Chawner, H, primary, Gomez, H L, primary, Matsuura, M, primary, Priestley, F, primary, and Wesson, R, primary

Published
2019
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109. H α fluxes and extinction distances for planetary nebulae in the IPHAS survey of the northern galactic plane.

Author

Dharmawardena, Thavisha E, Barlow, M J, Drew, J E, Seales, A, Sale, S E, Jones, D, Mampaso, A, Parker, Q A, Sabin, L, and Wesson, R

Subjects
PLANETARY nebulae, INTERPLANETARY dust, DISTANCES, INTERSTELLAR reddening, FLUX (Energy)
Abstract

We report H α filter photometry for 197 Northern hemisphere planetary nebulae (PNe) obtained using imaging data from the IPHAS survey. H α+[N  ii ] fluxes were measured for 46 confirmed or possible PNe discovered by the IPHAS survey and for 151 previously catalogued PNe that fell within the area of the northern Galactic Plane surveyed by IPHAS. After correcting for [N  ii ] emission admitted by the IPHAS H α filter, the resulting H α fluxes were combined with published radio free–free fluxes and H β fluxes, in order to estimate mean optical extinctions to 143 PNe using ratios involving their integrated Balmer line fluxes and their extinction-free radio fluxes. Distances to the PNe were then estimated using three different 3D interstellar dust extinction mapping methods, including the IPHAS-based h-mead algorithm of Sale (2014). These methods were used to plot dust extinction versus distance relationships for the lines of sight to the PNe; the intercepts with the derived dust optical extinctions allowed distances to the PNe to be inferred. For 17 of the PNe in our sample reliable Gaia DR2 distances were available and these have been compared with the distances derived using three different extinction mapping algorithms as well as with distances from the nebular radius versus H α surface brightness relation of Frew et al. (2016). That relation and the h-mead extinction mapping algorithm yielded the closest agreement with the Gaia DR2 distances. [ABSTRACT FROM AUTHOR]

Published
2021
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110. Sketch-Thru-Plan: A Multimodal Interface for Command and Control.

Author

COHEN, PHILIP R., KAISER, EDWARD C., BUCHANAN, M. CECELIA, LIND, SCOTT, CORRIGAN, MICHAEL J., and WESSON, R. MATTHEWS

Subjects
MULTIMODAL user interfaces, USER interfaces, COMPUTER interfaces, GRAPHICAL user interfaces, COMMAND & control systems, COMPUTER training
Abstract

The article offers a description of a fusion-based multimodal map system called Sketch-Thru-Plan (STP), that enables the rapid creation of operational plans with command and control (C2) software for military ground operations. Topics include the Deep Green program of DARPA (the U.S. Defense Advanced Research Projects Agency); user interfaces such as Graphical User Interface (GUI) and mobile interfaces that utilize speech, touch and handwriting; and the training requirements for various interface systems.

Published
2015
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111. Resolved Imaging of the AR Puppis Circumbinary Disk

Author

Ertel, S., primary, Kamath, D., additional, Hillen, M., additional, van Winckel, H., additional, Okumura, J., additional, Manick, R., additional, Boffin, H. M. J., additional, Milli, J., additional, Bertrang, G. H.-M., additional, Guzman-Ramirez, L., additional, Horner, J., additional, Marshall, J. P., additional, Scicluna, P., additional, Vaz, A., additional, Villaver, E., additional, Wesson, R., additional, and Xu, S., additional

Published
2019
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117. Initial clinical efficacy of 3-mm implants immediately placed into function in conditions of limited spacing.

Author

Reddy MS, O'Neal SJ, Haigh S, Aponte-Wesson R, and Geurs NC

Abstract

PURPOSE: The objective of this study was to determine changes in interdental papillae, alveolar bone loss, esthetics, and initial healing survival when 1-piece narrow-diameter implants were immediately loaded in sites with limited tooth-to-tooth spacing. MATERIALS AND METHODS: One-piece titanium alloy implants with a maximum diameter of 3.0 mm and a resorbable blast surface texture on a square-thread form were evaluated. Digital photographs were made at each clinical visit to assess soft tissue healing. Interproximal soft tissue fill of the embrasure was assessed with a modified Jemt index. Standardized radiographs were made at baseline (implant placement) and at 6 and 12 months postsurgery. Radiographic bone height was measured from a consistent landmark on the implant. A 1-sided t test was used to determine statistical differences of bone height. RESULTS: Thirty-one implants were placed in 17 subjects. One implant had clinical mobility and was removed, for an overall survival rate of 96.7%. Mean bone height on the day of placement and restoration was 2.33 + 0.73 mm above the first thread. Mean bone height was 1.75 +/- 0.78 mm at 6 months postrestoration and 1.63 +/- 0.81 mm at 12 months postrestoration. There was a statistically significant loss of bone support over the initial 6 months (0.58 mm; P < .01), with no significant progression thereafter (0.12 mm; NS). Complete fill of papillae was found in 92% of maxillary lateral incisor sites and 60% of mandibular incisor sites. CONCLUSION: The use of 1-piece narrow-diameter immediately loaded implants appears to be an effective prosthetic treatment for areas of limited space. [ABSTRACT FROM AUTHOR]

Published
2008

126. Mm-wave and far-IR Molecular line survey of OH 231.8+4.2: Hard-boiled rotten eggs

Author

Sánchez Contreras, C., Velilla, L., Alcolea, J., Quintana-Lacaci, G., Cernicharo, J., Agundez, M., Teyssier, D., Bujarrabal, V., Castro-Carrizo, A., Daniel, F., Fonfria, J. P., Garcia-Lario, P., Goicoechea, J. R., Herpin, F., Michael Barlow, Cherchneff, I., Comito, C., Cordiner, M., Decin, L., Halfen, D. T., Justtanont, K., Latter, W., Malloci, G., Matsuura, M., Menten, K., Mulas, G., Muller, H. S. P., Pardo, J. R., Pearson, J., Swinyward, B., Tenenbaum, E., Wesson, R., Wyrowski, F., Ziurys, L., Pomies, Marie-Paule, Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), SSE 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), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL), FORMATION STELLAIRE 2014, Max Planck Institute for Radio Astronomy, Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], Department of Physics and Astronomy [UCL London], University College of London [London] (UCL), INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), 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), Max-Planck-Institut für Radioastronomie (MPIFR), Instituto de RadioAstronomía Milimétrica ( IRAM ), Centre National de la Recherche Scientifique ( CNRS ), Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid 28850, Spain, Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid, 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'Etude du Rayonnement et de la Matière en Astrophysique ( LERMA ), École normale supérieure - Paris ( ENS Paris ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université de Cergy Pontoise ( UCP ), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique ( CNRS ), École normale supérieure - Paris ( ENS Paris ), Ctr Astrobiol CSIC INTA, Lab Astofis Mol, Madrid 28850, Max Planck Inst Radioastron, D-53121 Bonn, Germany, Max Planck Inst Radioastronomy, Onsala Space Observatory ( OSO ), University College of London [London] ( UCL ), Osservatorio Astronomico di Cagliari, Ist Nazl Astrofis, Osservatorio Astronomico di Cagliari, 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 ), Max-Planck-Institut für Radioastronomie ( MPIFR ), 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), École normale supérieure - Paris (ENS Paris), 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
[ PHYS.ASTR.SR ] Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], stars: planetary nebulae, [PHYS.ASTR.SR] Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.SR] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], planetary nebulae: general, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [ SDU.ASTR.SR ] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR]
Abstract

International audience; Envelopes around evolved stars are extraordinarily efficient factories of complex molecules and dust particles that will eventually enrich the ISM. To date, most chemistry studies have focused on C-rich envelopes, expected to show the largest molecular variety and abundances. Recent observations suggest that O-rich shells may be as chemically diverse as their Carbon counterparts, however, no serious attempt has been made yet to perform a full frequency scan of such objects. In this conference, I will report the first results from our spectral line surveys with the IRAM 30m telescope (~80-345 GHz) and Herschel/HIFI (~479-1244 GHz) of the well known, O-rich pre-PN OH 231.8+4.2 (a.k.a. The Rotten Egg nebula after the high abundance of Hydrogen sulfide, H2S, in its envelope). This object displays fast (>400 km/s), bipolar outflows and a molecular richness unparalleled amongst O-rich AGB and post-AGB stars. These surveys have led to the detection of hundreds of lines from different species, many of them detected for the first time in O-rich CSEs, that clearly confirm OH231.8+4.2 as the ''The Rosetta-stone'' for studying non-equilibrium, shock-induced molecule formation processes in O-rich environments. HIFI data have been particularly crucial to trace the physico-chemical conditions in the warm, dense circumstellar layers, which are not proved by lower-energy/frequency transitions. At these high frequencies, H2O and S-containing species are, together with CO, the dominant contributors to the total line flux observed. The main product from these surveys, is a molecular inventory and unprecentedly detailed chemical study (in progress) of an O-rich molecular flow accelerated by fast shocks.

Published
2014

128. Herschel observations of PNe in the MESS key program

Author

Hoof, P. A. M., Barlow, M. J., Griet Van de Steene, Exter, K. M., Wesson, R., Ottensamer, R., Lim, T. L., Sibthorpe, B., Matsuura, M., Ueta, T., Winckel, H., Waelkens, C., and Mess Consortium, The

Subjects
Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

In this paper we give a progress report on the Herschel imaging and spectroscopic observations of planetary nebulae that are carried out as part of the MESS guaranteed time key program. We present and discuss imaging and temperature maps of NGC 6720, NGC 650, and NGC 6853, as well as PACS and SPIRE spectroscopy of NGC 7027., 4 pages, 5 figures, proceedings IAU Symposium 283 Planetary Nebulae: An Eye to the Future

Published
2011

131. Herschel imaging of the dust in the Helix nebula (NGC 7293)

Author

Van de Steene, G. C., van Hoof, P. A. M., Exter, K. M., Barlow, M. J., Cernicharo, J., Etxaluze, M., Gear, W. K., Goicoechea, J. R., Gomez, H. L., Groenewegen, M. A. T., Hargrave, P. C., Ivison, R. J., Leeks, S. J., Lim, T. L., Matsuura, M., Olofsson, Göran, Polehampton, E. T., Swinyard, B. M., Ueta, T., Van Winckel, H., Waelkens, C., Wesson, R., Van de Steene, G. C., van Hoof, P. A. M., Exter, K. M., Barlow, M. J., Cernicharo, J., Etxaluze, M., Gear, W. K., Goicoechea, J. R., Gomez, H. L., Groenewegen, M. A. T., Hargrave, P. C., Ivison, R. J., Leeks, S. J., Lim, T. L., Matsuura, M., Olofsson, Göran, Polehampton, E. T., Swinyard, B. M., Ueta, T., Van Winckel, H., Waelkens, C., and Wesson, R.

Abstract

Aims. In our series of papers presenting the Herschel imaging of evolved planetary nebulae, we present images of the dust distribution in the Helix nebula (NGC 7293). Methods. Images at 70, 160, 250, 350, and 500 mu m were obtained with the PACS and SPIRE instruments on board the Herschel satellite. Results. The broadband maps show the dust distribution over the main Helix nebula to be u npy and predominantly present in the barrel wall. We determined the spectral energy distribution of the main nebula in a consistent way using Herschel. IRAS. and Planck flux values, The emissivity index of beta = 0.99 +/- 0.09, in combination with the carbon rich molecular chemistry of the nebula, indicates that the dust consists mainly of amorphous carbon. The dust excess emission from the central star disk is detected at 70 pm and the flux measurement agrees with previous measurement. We present the temperature and dust column density maps. The total dust mass across the Helix nebula (without its halo) is determined to be 3.5 x 10(-3) M-circle dot at a distance of 216 pc. The temperature map shows dust temperatures between 22 K and 42 K, which is similar to the kinetic temperature of the molecular gas, confirming that the dust and gas co exist in high density clumps. Archived images are used to compare the location of the dust emission in the far infrared (Herschel) with the ionized (GALEX and H-beta) and molecular (H-2) component. The different emission components are consistent with the Helix consisting of a thick walled barrel-like structure inclined to the line of sight. The radiation field decreases rapidly through the barrel wall., AuthorCount:22

Published
2015
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132. Witnessing the emergence of a carbon star

Author

Guzman-Ramirez, L, Lagadec, Eric, Wesson, R, Zijlstra, Albert A, Muller, A, Jones, D, Boffin, H. M. J., Sloan, G C, Redman, M.P., Smette, Alain, Karakas, Amanda, Nyman, Lars-Åke, Guzman-Ramirez, L, Lagadec, Eric, Wesson, R, Zijlstra, Albert A, Muller, A, Jones, D, Boffin, H. M. J., Sloan, G C, Redman, M.P., Smette, Alain, Karakas, Amanda, and Nyman, Lars-Åke

Abstract

During the late stages of their evolution, Sun-like stars bring the products of nuclear burning to the surface. Most of the carbon in the Universe is believed to originate from stars with masses up to a few solar masses. Although there is a chemical dichotomy between oxygen-rich and carbon-rich evolved stars, the dredge-up itself has never been directly observed. In the last three decades, however, a few stars have been shown to display both carbon-and oxygen-rich material in their circumstellar envelopes. Two models have been proposed to explain this dual chemistry: one postulates that a recent dredge-up of carbon produced by nucleosynthesis inside the star during the Asymptotic Giant Branch changed the surface chemistry of the star. The other model postulates that oxygen-rich material exists in stable keplerian rotation around the central star. The two models make contradictory, testable, predictions on the location of the oxygen-rich material, either located further from the star than the carbon-rich gas, or very close to the star in a stable disc. Using the FaintObject InfraRed CAmera (FORCAST) instrument on board the Stratospheric Observatory for Infrared Astronomy (SOFIA) Telescope, we obtained images of the carbon-rich planetary nebula BD +30° 3639 which trace both carbon-rich polycyclic aromatic hydrocarbons and oxygen-rich silicate dust. With the superior spectral coverage of SOFIA, and using a 3D photoionization and dust radiative transfer model we prove that the O-rich material is distributed in a shell in the outer parts of the nebula, while the C-rich material is located in the inner parts of the nebula. These observations combined with the model, suggest a recent change in stellar surface composition for the double chemistry in this object. This is evidence for dredge-up occurring ~ 103 yr ago.

Published
2015

135. Imaging Planetary Nebulae with Herschel-PACS and SPIRE

Author

Hoof, P. A. M., Exter, K. M., Steene, G. C., Michael Barlow, Lim, T. L., Sibthorpe, B., Groenewegen, M. A. T., Ueta, T., Matsuura, M., Blommaert, J. A. D. L., Cohen, M., Meester, W., Gear, W. K., Gomez, H. L., Hargrave, P. C., Huygen, E., Ivison, R. J., Jean, C., Leeks, S. J., Olofsson, G., Polehampton, E. T., Regibo, S., Royer, P., Swinyard, B. M., Vandenbussche, B., Winckel, H., Waelkens, C., and Wesson, R.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics
Abstract

In this paper we will discuss the images of Planetary Nebulae that have recently been obtained with PACS and SPIRE on board the Herschel satellite. This comprises results for NGC 650 (the little Dumbbell nebula), NGC 6853 (the Dumbbell nebula), and NGC 7293 (the Helix nebula)., 4 pages, 3 figures; proceedings of the Asymmetrical Planetary Nebulae 5 conference

Published
2010

137. New OB star candidates in the Carina Arm around Westerlund 2 from VPHAS+

Author

Mohr-Smith, M., primary, Drew, J. E., additional, Barentsen, G., additional, Wright, N. J., additional, Napiwotzki, R., additional, Corradi, R. L. M., additional, Eislöffel, J., additional, Groot, P., additional, Kalari, V., additional, Parker, Q. A., additional, Raddi, R., additional, Sale, S. E., additional, Unruh, Y. C., additional, Vink, J. S., additional, and Wesson, R., additional

Published
2015
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138. Witnessing the emergence of a carbon star

Author

Guzman-Ramirez, L., primary, Lagadec, E., additional, Wesson, R., additional, Zijlstra, A. A., additional, Müller, A., additional, Jones, D., additional, Boffin, H. M. J., additional, Sloan, G. C., additional, Redman, M. P., additional, Smette, A., additional, Karakas, A. I., additional, and Nyman, Lars-Åke, additional

Published
2015
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139. Sketch-Thru-Plan

Author

Cohen, Philip R., primary, Kaiser, Edward C., additional, Buchanan, M. Cecelia, additional, Lind, Scott, additional, Corrigan, Michael J., additional, and Wesson, R. Matthews, additional

Published
2015
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140. The β Pictoris disk imaged by Herschel PACS and SPIRE [Letter]

Author

Vandenbussche, B., Sibthorpe, B., Acke, B., Pantin, E., Olofsson, G., Waelkens, C., Dominik, C., Barlow, M. J., Blommaert, J. A. D. L., Bouwman, J., Brandeker, A., Cohen, M., De Meester, W., Dent, W. R. F., Exter, K., Di Francesco, J., Fridlund, M., Gear, Walter Kieran, Glauser, A. M., Gomez, Haley Louise, Greaves, J. S., Hargrave, Peter Charles, Harvey, P. M., Henning, Th., Heras, A. M., Hogerheijde, M. R., Holland, W. S., Huygen, R., Ivison, R. J., Jean, C., Leeks, S. J., Lim, T. L., Liseau, R., Matthews, B. C., Naylor, D. A., Pilbratt, G. L., Polehampton, E. T., Regibo, S., Royer, P., Sicilia-Aguilar, A., Swinyard, B. M., Walker, H. J., and Wesson, R.

Subjects
QB
Abstract

We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star β Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 μm. The surface brightness profiles between 70 and 160 μm show no significant asymmetries along the disk, and are compatible with 90% of the emission between 70 and 160 μm originating in a region closer than 200 AU to the star. Although only marginally resolving the debris disk, the maps obtained in the SPIRE 250–500 μm filters provide full-disk photometry, completing the SED over a few octaves in wavelength that had been previously inaccessible. The small far-infrared spectral index (β = 0.34) indicates that the grain size distribution in the inner disk (

Published
2010

141. Silicon in the dust formation zone of IRC+10216 [Letter]

Author

Decin, L., Cernicharo, J., Barlow, M. J., Royer, P., Vandenbussche, B., Wesson, R., Polehampton, E. T., De Beck, E., Agúndez, M., Blommaert, J. A. D. L., Cohen, M., Daniel, F., De Meester, W., Exter, K., Feuchtgruber, H., Fonfría, J. P., Gear, Walter Kieran, Goicoechea, J. R., Gomez, Haley Louise, Groenewegen, M. A. T., Hargrave, Peter Charles, Huygen, R., Imhof, P., Ivison, R. J., Jean, C., Kerschbaum, F., Leeks, S. J., Lim, T., Matsuura, Mikako, Olofsson, G., Posch, T., Regibo, S., Savini, G., Sibthorpe, B., Swinyard, B. M., Tercero, B., Waelkens, C., Witherick, D. K., and Yates, J. A.

Subjects
QB
Abstract

The interstellar medium is enriched primarily by matter ejected from evolved low and intermediate mass stars. The outflows from these stars create a circumstellar envelope in which a rich gas-phase and dust-nucleation chemistry takes place. We observed the nearest carbon-rich evolved star, IRC +10216, using the PACS (55–210 μm) and SPIRE (194–672 μm) spectrometers on board Herschel. We find several tens of lines from SiS and SiO, including lines from the v = 1 vibrational level. For SiS these transitions range up to J = 124–123, corresponding to energies around 6700 K, while the highest detectable transition is J = 90–89 for SiO, which corresponds to an energy around 8400 K. Both species trace the dust formation zone of IRC +10216, and the broad energy ranges involved in their detected transitions permit us to derive the physical properties of the gas and the particular zone in which each species has been formed. This allows us to check the accuracy of chemical thermodynamical equilibrium models and the suggested depletion of SiS and SiO due to accretion onto dust grains.

Published
2010

142. In-flight calibration of the Herschel-SPIRE instrument [Letter]

Author

Swinyard, B. M., Ade, Peter A. R., Baluteau, J.-P., Aussel, H., Barlow, M. J., Bendo, G. J., Benielli, D., Bock, J., Brisbin, D., Conley, A., Conversi, L., Dowell, A., Dowell, D., Ferlet, M., Fulton, T., Glenn, J., Glauser, A., Griffin, D., Griffin, Matthew Joseph, Guest, S., Imhof, P., Isaak, Kate Gudrun, Jones, S., King, K., Leeks, S., Levenson, L., Lim, T. L., Lu, N., Makiwa, G., Naylor, D., Nguyen, H., Oliver, S., Panuzzo, P., Papageorgiou, Andreas, Pearson, C., Pohlen, Michael, Polehampton, E., Pouliquen, D., Rigopoulou, D., Ronayette, S., Roussel, H., Rykala, Adam John, Savini, G., Schulz, B., Schwartz, A., Shupe, D., Sibthorpe, B., Sidher, S., Smith, A. J., Spencer, Locke, Trichas, M., Triou, H., Valtchanov, I., Wesson, R., Woodcraft, A., Xu, C. K., Zemcov, M., and Zhang, L.

Subjects
Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics, QB
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 μm, and an imaging Fourier-transform spectrometer (FTS) covering 194–671 μm (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.

Published
2010

143. The �� Pictoris disk imaged by Herschel PACS and SPIRE

Author

Vandenbussche, B., Sibthorpe, B., Acke, B., Pantin, E., Olofsson, G., Waelkens, C., Dominik, C., Barlow, M. J., Blommaert, J. A. D. L., Bouwman, J., Brandeker, A., Cohen, M., DeMeester, W., Dent, W. R. F., Exter, K., Di Francesco, J., Fridlund, M., Gear, W. K., Glauser, A. M., Gomez, H. L., Greaves, J. S., Hargrave, P. C., Harvey, P. M., Henning, Th., Heras, A. M., Hogerheijde, M. R., Holland, W. S., Huygen, R., Ivison, R. J., Jean, C., Leeks, S. J., Lim, T. L., Liseau, R., Matthews, B. C., Naylor, D. A., Pilbratt, G. L., Polehampton, E. T., Regibo, S., Royer, P., Sicilia-Aguilar, A., Swinyard, B. M., Walker, H. J., and Wesson, R.

Subjects
FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star �� Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 ��m. The surface brightness profiles between 70 and 160 ��m show no significant asymmetries along the disk, and are compatible with 90% of the emission between 70 and 160 ��m originating in a region closer than 200 AU to the star. Although only marginally resolving the debris disk, the maps obtained in the SPIRE 250 - 500 ��m filters provide full-disk photometry, completing the SED over a few octaves in wavelength that had been previously inaccessible. The small far-infrared spectral index (�� = 0.34) indicates that the grain size distribution in the inner disk (, Accepted for publication in Astronomy&Astrophysics, Herschel First Results special issue

Published
2010
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144. Herschel images of NGC 6720: H2 formation on dust grains [Letter]

Author

van Hoof, P. A. M., Van de Steene, G. C., Barlow, M. J., Exter, K. M., Sibthorpe, B., Ueta, T., Peris, V., Groenewegen, M. A. T., Blommaert, J. A. D. L., Cohen, M., De Meester, W., Ferland, G. J., Gear, Walter Kieran, Gomez, Haley Louise, Hargrave, Peter Charles, Huygen, E., Ivison, R. J., Jean, C., Leeks, S. J., Lim, T. L., Olofsson, G., Polehampton, E. T., Regibo, S., Royer, P., Swinyard, B. M., Vandenbussche, B., Van Winckel, H., Waelkens, C., Walker, H. J., and Wesson, R.

Subjects
Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, QB
Abstract

Herschel PACS and SPIRE images have been obtained of NGC 6720 (the Ring nebula). This is an evolved planetary nebula with a central star that is currently on the cooling track, due to which the outer parts of the nebula are recombining. From the PACS and SPIRE images we conclude that there is a striking resemblance between the dust distribution and the H2 emission, which appears to be observational evidence that H2 forms on grain surfaces. We have developed a photoionization model of the nebula with the Cloudy code which we used to determine the physical conditions of the dust and investigate possible formation scenarios for the H2. We conclude that the most plausible scenario is that the H2 resides in high density knots which were formed after the recombination of the gas started when the central star entered the cooling track. Hydrodynamical instabilities due to the unusually low temperature of the recombining gas are proposed as a mechanism for forming the knots. H2 formation in the knots is expected to be substantial after the central star underwent a strong drop in luminosity about one to two thousand years ago, and may still be ongoing at this moment, depending on the density of the knots and the properties of the grains in the knots.

Published
2010

145. Detection of anhydrous hydrochloric acid, HCl, in IRC + 10216 with the Herschel SPIRE and PACS spectrometers [Letter]

Author

Cernicharo, J., Decin, L., Barlow, M. J., Agúndez, M., Royer, P., Vandenbussche, B., Wesson, R., Polehampton, E. T., De Beck, E., Blommaert, J. A. D. L., Daniel, F., De Meester, W., Exter, K. M., Feuchtgruber, H., Gear, Walter Kieran, Goicoechea, J. R., Gomez, Haley Louise, Groenewegen, M. A. T., Hargrave, Peter Charles, Huygen, R., Imhof, P., Ivison, R. J., Jean, C., Kerschbaum, F., Leeks, S. J., Lim, T. L., Matsuura, Mikako, Olofsson, G., Posch, T., Regibo, S., Savini, G., Sibthorpe, B., Swinyard, B. M., and Waelkens, C.

Subjects
QB
Abstract

We report on the detection of anhydrous hydrochloric acid (hydrogen chlorine, HCl) in the carbon-rich star IRC +10216 using the spectroscopic facilities onboard the Herschel satellite. Lines from J = 1–0 up to J = 7–6 have been detected. From the observed intensities, we conclude that HCl is produced in the innermost layers of the circumstellar envelope with an abundance relative to H2 of 5 × 10-8 and extends until the molecules reach its photodissociation zone. Upper limits to the column densities of AlH, MgH, CaH, CuH, KH, NaH, FeH, and other diatomic hydrides have also been obtained.

Published
2010

146. PACS and SPIRE spectroscopy of the red supergiant VY CMa [Letter]

Author

Royer, P., Decin, L., Wesson, R., Barlow, M. J., Polehampton, E. T., Matsuura, Mikako, Agúndez, M., Blommaert, J. A. D. L., Cernicharo, J., Cohen, M., Daniel, F., Degroote, P., De Meester, W., Exter, K., Feuchtgruber, H., Gear, Walter Kieran, Gomez, Haley Louise, Groenewegen, M. A. T., Hargrave, Peter Charles, Huygen, R., Imhof, P., Ivison, R. J., Jean, C., Kerschbaum, F., Leeks, S. J., Lim, T., Lombaert, R., Olofsson, G., Posch, T., Regibo, S., Savini, G., Sibthorpe, B., Swinyard, B. M., Vandenbussche, B., Waelkens, C., Witherick, D. K., and Yates, J. A.

Subjects
QB
Abstract

With a luminosity >105 and a mass-loss rate of ~2 × 10-4 yr-1, the red supergiant VY CMa truly is a spectacular object. Because of its extreme evolutionary state, it could explode as supernova any time. Studying its circumstellar material, into which the supernova blast will run, provides interesting constraints on supernova explosions and on the rich chemistry taking place in such complex circumstellar envelopes. We have obtained spectroscopy of VY CMa over the full wavelength range offered by the PACS and SPIRE instruments of Herschel, i.e. 55–672 micron. The observations show the spectral fingerprints of more than 900 spectral lines, of which more than half belong to water. In total, we have identified 13 different molecules and some of their isotopologues. A first analysis shows that water is abundantly present, with an ortho-to-para ratio as low as ~1.3:1, and that chemical non-equilibrium processes determine the abundance fractions in the inner envelope.

Published
2010

147. Herschel PACS and SPIRE imaging of CW Leonis [Letter]

Author

Ladjal, D., Barlow, M. J., Groenewegen, M. A. T., Ueta, T., Blommaert, J. A. D. L., Cohen, M., Decin, L., De Meester, W., Exter, K., Gear, Walter Kieran, Gomez, Haley Louise, Hargrave, Peter Charles, Huygen, R., Ivison, R. J., Jean, C., Kerschbaum, F., Leeks, S. J., Lim, T. L., Olofsson, G., Polehampton, E., Posch, T., Regibo, S., Royer, P., Sibthorpe, B., Swinyard, B. M., Vandenbussche, B., Waelkens, C., and Wesson, R.

Subjects
QB
Abstract

Herschel PACS and SPIRE images have been obtained over a 30' × 30' area around the well-known carbon star CW Leo (IRC +10 216). An extended structure is found in an incomplete arc of ~22' diameter, which is cospatial with the termination shock due to interaction with the interstellar medium (ISM) as defined by Sahai & Chronopoulos from ultraviolet GALEX images. Fluxes are derived in the 70, 160, 250, 350, and 550 μm bands in the region where the interaction with the ISM takes place, and this can be fitted with a modified black body with a temperature of 25 ± 3 K. Using the published proper motion and radial velocity for the star, we derive a heliocentric space motion of 25.1 km s-1. Using the PACS and SPIRE data and the analytical formula of the bow shock structure, we infer a de-projected standoff distance of the bow shock of R0 = (8.0 ± 0.3) × 1017 cm. We also derive a relative velocity of the star with respect to the ISM of (106.6 ± 8.7)/ km s-1, where nISM is the number density of the local ISM.

Published
2010

148. The dust mass in Cassiopeia A from a spatially resolved Herschel analysis.

Author

De Looze, I., Barlow, M. J., Swinyard, B. M., Rho, J., Gomez, H. L., Matsuura, M., and Wesson, R.

Subjects
COSMIC dust, SUPERNOVA remnants, ASTRONOMICAL observations, INTERSTELLAR medium, CASSIOPEIA (Constellation)
Abstract

Theoretical models predict that core-collapse supernovae (CCSNe) can be efficient dust producers (0.1-1.0 M☉), potentially accounting for most of the dust production in the early Universe. Observational evidence for this dust production efficiency is however currently limited to only a few CCSN remnants (e.g. SN 1987A, Crab nebula). In this paper, we revisit the dust mass produced in Cassiopeia A (Cas A), a ~330-yr old O-rich Galactic supernova remnant (SNR) embedded in a dense interstellar foreground and background. We present the first spatially resolved analysis of Cas A based on Spitzer and Herschel infrared and submillimetre data at a common resolution of ~0.6 arcmin for this 5 arcmin diameter remnant following a careful removal of contaminating line emission and synchrotron radiation. We fit the dust continuum from 17 to 500 μm with a four-component interstellar medium and supernova (SN) dust model.We find a concentration of cold dust in the unshocked ejecta of Cas A and derive a mass of 0.3-0.5M☉ of silicate grains freshly produced in the SNR, with a lower limit of ≥0.1- 0.2 M☉. For a mixture of 50 per cent of silicate-type grains and 50 per cent of carbonaceous grains, we derive a total SN dust mass between 0.4 and 0.6M☉. These dust mass estimates are higher than from most previous studies of Cas A and support the scenario of SN-dominated dust production at high redshifts. We furthermore derive an interstellar extinction map for the field around Cas A which towards Cas A gives average values of AV = 6-8 mag, up to a maximum of AV = 15 mag. [ABSTRACT FROM AUTHOR]

Published
2017
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149. Herschelimaging of the dust in the Helix nebula (NGC 7293)

Author

Van de Steene, G. C., primary, van Hoof, P. A. M., additional, Exter, K. M., additional, Barlow, M. J., additional, Cernicharo, J., additional, Etxaluze, M., additional, Gear, W. K., additional, Goicoechea, J. R., additional, Gomez, H. L., additional, Groenewegen, M. A. T., additional, Hargrave, P. C., additional, Ivison, R. J., additional, Leeks, S. J., additional, Lim, T. L., additional, Matsuura, M., additional, Olofsson, G., additional, Polehampton, E. T., additional, Swinyard, B. M., additional, Ueta, T., additional, Van Winckel, H., additional, Waelkens, C., additional, and Wesson, R., additional

Published
2015
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150. The VST Photometric Hα Survey of the Southern Galactic Plane and Bulge (VPHAS+)

Author

Drew, J.E., Gonzalez-Solares, E., Greimel, R., Irwin, M.J., Yoldas, A. Küpcü, Lewis, J., Barentsen, G., Eislöffel, J., Farnhill, H.J., Martin, W.E., Walsh, J.R., Walton, N.A., Mohr-Smith, M., Raddi, R., Sale, S.E., Wright, N.J., Groot, P.J., Barlow, M.J., Corradi, R.L.M., Drake, J.J., Fabregat, J., Frew, D.J., Gänsicke, B.T., Knigge, C., Mampaso, A., Morris, R.A.H., Naylor, T., Parker, Q.A., Phillipps, S., Ruhland, C., Steeghs, D., Unruh, Y.C., Vink, J.S., Wesson, R., Zijlstra, A.A., Drew, J.E., Gonzalez-Solares, E., Greimel, R., Irwin, M.J., Yoldas, A. Küpcü, Lewis, J., Barentsen, G., Eislöffel, J., Farnhill, H.J., Martin, W.E., Walsh, J.R., Walton, N.A., Mohr-Smith, M., Raddi, R., Sale, S.E., Wright, N.J., Groot, P.J., Barlow, M.J., Corradi, R.L.M., Drake, J.J., Fabregat, J., Frew, D.J., Gänsicke, B.T., Knigge, C., Mampaso, A., Morris, R.A.H., Naylor, T., Parker, Q.A., Phillipps, S., Ruhland, C., Steeghs, D., Unruh, Y.C., Vink, J.S., Wesson, R., and Zijlstra, A.A.

Abstract

Contains fulltext : 127903.pdf (preprint version ) (Open Access)

Published
2014

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