Year: 2010
Type: article
Abstract: We present the first results from the science demonstration phase for the Hi-GAL survey, the Herschel key program that will map the inner Galactic plane of the Milky Way in 5 bands. We outline our data reduction strategy and present some science highlights on the two observed 2° × 2° tiles approximately centered at l = 30° and l = 59°. The two regions are extremely rich in intense and highly structured extended emission which shows a widespread organization in filaments. Source SEDs can be built for hundreds of objects in the two fields, and physical parameters can be extracted, for a good fraction of them where the distance could be estimated. The compact sources (which we will call cores' in the following) are found for the most part to be associated with the filaments, and the relationship to the local beam-averaged column density of the filament itself shows that a core seems to appear when a threshold around AV ~ 1 is exceeded for the regions in the l = 59° field; a AV value between 5 and 10 is found for the l = 30° field, likely due to the relatively higher distances of the sources. This outlines an exciting scenario where diffuse clouds first collapse into filaments, which later fragment to cores where the column density has reached a critical level. In spite of core L/M ratios being well in excess of a few for many sources, we find core surface densities between 0.03 and 0.5 g cm-2. Our results are in good agreement with recent MHD numerical simulations of filaments forming from large-scale converging flows.
Source: Astronomy and Astrophysics
Authors: S. Molinari, B. Swinyard, J. Bally, M. Barlow, J.-P. Bernard, P. Martin, T. Moore, A. Noriega-Crespo, R. Plume, L. Testi, A. Zavagno, A. Abergel, B. Ali, L. Anderson, P. André, J.-P. Baluteau, C. Battersby, M. T. Beltrán, M. Benedettini, N. Billot, J. Blommaert, S. Bontemps, F. Boulanger, J. Brand, C. Brunt, M. Burton, L. Calzoletti, S. Carey, P. Caselli, R. Cesaroni, J. Cernicharo, S. Chakrabarti, A. Chrysostomou, M. Cohen, M. Compiegne, P. de Bernardis, G. de Gasperis, A. M. di Giorgio, D. Elia, F. Faustini, N. Flagey, Y. Fukui, G. A. Fuller, K. Ganga, P. Garcia-Lario, J. Glenn, P. F. Goldsmith, M. Griffin, M. Hoare, M. Huang, D. Ikhenaode, C. Joblin, G. Joncas, M. Juvela, J. M. Kirk, G. Lagache, J. Z. Li, T. L. Lim, S. D. Lord, M. Marengo, D. J. Marshall, S. Masi, F. Massi, M. Matsuura, V. Minier, M.-A. Miville-Deschênes, L. A. Montier, L. Morgan, F. Motte, J. C. Mottram, T. G. Müller, P. Natoli, J. Neves, L. Olmi, R. Paladini, D. Paradis, H. Parsons, N. Peretto, M. Pestalozzi, S. Pezzuto, F. Piacentini, L. Piazzo, D. Polychroni, M. Pomarès, C. C. Popescu, W. T. Reach, I. Ristorcelli, J.-F. Robitaille, T. Robitaille, J. A. Rodón, A. Roy, P. Royer, D. Russeil, P. Saraceno, M. Sauvage, P. Schilke, E. Schisano, N. Schneider, F. Schuller, B. Schulz, B. Sibthorpe, H. A. Smith, M. D. Smith, L. Spinoglio, D. Stamatellos, F. Strafella, G. S. Stringfellow, E. Sturm, R. Taylor, M. A. Thompson, A. Traficante, R. J. Tuffs, G. Umana, L. Valenziano, R. Vavrek, M. Veneziani, S. Viti, C. Waelkens, D. Ward-Thompson, G. White, L. A. Wilcock, F. Wyrowski, H. W. Yorke, Q. Zhang
Institutions: National Institute for Astrophysics, Rutherford Appleton Laboratory, University of Colorado Boulder, University College London, Centre National de la Recherche Scientifique, Université Toulouse III - Paul Sabatier, Université de Toulouse, University of Toronto, Liverpool John Moores University, California Institute of Technology, University of Calgary, European Southern Observatory, Arcetri Astrophysical Observatory, Aix-Marseille Université, Université de Provence Aix-Marseille I, Université Paris-Sud, Institut d'Astrophysique Spatiale, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Astrophysique, Instrumentation et Modélisation, Université Paris Diderot, KU Leuven, Université de Bordeaux, Laboratoire d'Astrophysique de Bordeaux, Istituto di Radioastronomia di Bologna, University of Exeter, UNSW Sydney, Agenzia Spaziale Italiana, University of Leeds, Consejo Superior de Investigaciones Científicas, Centro de Astrobiología, University of California, Berkeley, University of Hawaii at Hilo, Canadian Institute for Theoretical Astrophysics, Sapienza University of Rome, University of Rome Tor Vergata, Nagoya University, University of Manchester, Laboratoire AstroParticule et Cosmologie, European Space Astronomy Centre, Jet Propulsion Laboratory, Cardiff University, Chinese Academy of Sciences, National Astronomical Observatories, Université Laval, University of Helsinki, Smithsonian Astrophysical Observatory, Center for Astrophysics Harvard & Smithsonian, Max Planck Institute for Extraterrestrial Physics, University of Hertfordshire, University of Lancashire, University of Cologne, University of Naples Federico II, University of Kent, University of Salento, Max Planck Institute for Nuclear Physics, Osservatorio Astrofisico di Catania, Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, The Open University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2156658280