EDP Sciences
Free access
Issue A&A
Volume 474, Number 3, November II 2007
Page(s) 883 - 890
Section Interstellar and circumstellar matter
DOI http://dx.doi.org/10.1051/0004-6361:20077197



A&A 474, 883-890 (2007)
DOI: 10.1051/0004-6361:20077197

A massive protostellar core with an infalling envelope

S. M. Birkmann1, O. Krause1, M. Hennemann1, Th. Henning1, J. Steinacker1, 2, and D. Lemke1

1  Max-Planck-Institut für Astronomie (MPIA), Königstuhl 17, 69117 Heidelberg, Germany
    e-mail: [birkmann;krause;hennemann;henning;stein;lemke]@mpia.de
2  Zentrum für Astronomie der Universität Heidelberg (ZAH), Mönchhofstr. 12-14, 69120 Heidelberg, Germany

(Received 30 January 2007 / Accepted 18 August 2007)

Abstract
Context.Due to the short timescales involved and observational difficulties, our knowledge of the earliest phases of massive star formation remains incomplete.
Aims.We aim to explore the physical conditions during the initial phases of high-mass star formation and to detect a genuine massive (mass M > 8 $M_\odot$) protostar at an early evolutionary stage.
Methods.We have launched a multi-wavelength study of young and massive star-forming regions that were identified by the ISOPHOT Serendipity Survey (ISOSS) performed with the ISO space telescope. The follow-up observations include ground-based near-infrared imaging and (sub)mm continuum and molecular line measurements (both single-dish and interferometric), as well as mid- to far-infrared measurements with the Spitzer Space Telescope. The combined spectrophotometric data are used to determine source temperatures T and masses M.
Results. ISOSS J23053+5953 is a massive (M ~ 900 $M_\odot$, luminosity L ~ 2100 $L_\odot$) and cold (T ~ 17 K) star-forming region with two protostellar/protocluster candidates (T $\la$ 20 K and T ~ 17.5 K, M ~ 200 $M_\odot$ each). The low temperatures are strongly confined by the spectrophotometric Spitzer data in the FIR. Interferometric observations reveal that the colder core (SMM2) has a mass of M = 26 $M_\odot$ within a region of 8700 $\times$ 5600 AU and drives an outflow. It also shows signs of infall in both single-dish and interferometric measurements, and its luminosity can be explained by accretion. We also detect a large-scale jet that is traced by H2 emission.
Conclusions.The cold mm-core ISOSS J23053+5953 SMM2 is a promising candidate for a high-mass protostar in an early evolutionary stage and one of the few objects showing both infall signatures and jets as a sign of accretion.


Key words: ISM: individual objects: ISOSS J23053+5953 -- stars: formation -- ISM: jets and outflows -- infrared: ISM -- ISM: kinematics and dynamics



© ESO 2007

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.

Editor-in-Chief: T. Forveille
Letters Editor-in-Chief: J. Alves
Managing Editor: C. Bertout

ISSN: 0004-6361 ; e-ISSN: 1432-0746
Frequency: 12 volumes per year
Published by: EDP Sciences

Mirror sites: CDS | EDP Sciences
  RSS feeds
© The European Southern Observatory (ESO)