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

Autor: Pierre Didelon, L. D. Anderson, Sergio Molinari, Doris Arzoumanian, Stefano Pezzuto, Nicola Schneider, Jason M. Kirk, Q. Nguyen Luong, Vincent Minier, G. Leuleu, J. Di Francesco, F. Louvet, Pierrick Martin, M. Benedettini, K. L. J. Rygl, Annie Zavagno, D. Russeil, T. Rayner, J. Bardagi, D. Polychroni, T. Nony, Ph. André, M. Figueira, Tracey Hill, J.-P. Bernard, P. Persi, Davide Elia, Vera Konyves, A. Rivera-Ingraham, G. J. White, H. Roussel, Luigi Spinoglio, J. Tigé, Sylvain Bontemps, M. Hennemann, Frédérique Motte
Přispěvatelé: Sciences pour l'environnement (SPE), Université Pascal Paoli (UPP)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (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), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), FORMATION STELLAIRE 2017, 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), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), Centro de Matemática e Aplicações Fundamentais (CMAF), Universidade de Lisboa = University of Lisbon (ULISBOA), Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Faculty of Informatics [Lugano], Università della Svizzera italiana = University of Italian Switzerland (USI), School of Physics and Astronomy [Cardiff], Cardiff University, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Antarctic Research a European Network for Astrophysics (ARENA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Engineering Department, University of Cambridge [UK] (CAM), Centre National de la Recherche Scientifique (CNRS)-Université Pascal Paoli (UPP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidade de Lisboa (ULISBOA), Consiglio Nazionale delle Ricerche (CNR), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), ITA, GBR, FRA, CAN
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Astronomy and Astrophysics-A&A
Astronomy and Astrophysics-A&A, 2017, 602, pp.A77. ⟨10.1051/0004-6361/201628989⟩
Astronomy and Astrophysics-A&A, EDP Sciences, 2017, 602, pp.A77. ⟨10.1051/0004-6361/201628989⟩
ISSN: 0004-6361
DOI: 10.1051/0004-6361/201628989⟩
Popis: Aims: To constrain models of high-mass star formation, the Herschel-HOBYS key program aims at discovering massive dense cores (MDCs) able to host the high-mass analogs of low-mass prestellar cores, which have been searched for over the past decade. We here focus on NGC 6334, one of the best-studied HOBYS molecular cloud complexes. Methods: We used Herschel/PACS and SPIRE 70-500 μm images of the NGC 6334 complex complemented with (sub)millimeter and mid-infrared data. We built a complete procedure to extract 0.1 pc dense cores with the getsources software, which simultaneously measures their far-infrared to millimeter fluxes. We carefully estimated the temperatures and masses of these dense cores from their spectral energy distributions (SEDs). We also identified the densest pc-scale cloud structures of NGC 6334, one 2 pc × 1 pc ridge and two 0.8 pc × 0.8 pc hubs, with volume-averaged densities of 105 cm-3. Results: A cross-correlation with high-mass star formation signposts suggests a mass threshold of 75 M☉ for MDCs in NGC 6334. MDCs have temperatures of 9.5-40 K, masses of 75-1000 M☉, and densities of 1 × 105-7 × 107 cm-3. Their mid-infrared emission is used to separate 6 IR-bright and 10 IR-quiet protostellar MDCs while their 70 μm emission strength, with respect to fitted SEDs, helps identify 16 starless MDC candidates. The ability of the latter to host high-mass prestellar cores is investigated here and remains questionable. An increase in mass and density from the starless to the IR-quiet and IR-bright phases suggests that the protostars and MDCs simultaneously grow in mass. The statistical lifetimes of the high-mass prestellar and protostellar core phases, estimated to be 1-7 × 104 yr and at most 3 × 105 yr respectively, suggest a dynamical scenario of high-mass star formation. Conclusions: The present study provides good mass estimates for a statistically significant sample, covering the earliest phases of high-mass star formation. High-mass prestellar cores may not exist in NGC 6334, favoring a scenario presented here, which simultaneously forms clouds, ridges, MDCs, and high-mass protostars. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. Catalogs built from Tables A.1-A.12, are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/602/A77
Databáze: OpenAIRE
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