Herschel observations of B1-bS and B1-bN: two first hydrostatic core candidates in the Perseus star-forming cloud

Journal
Date Issued
2012
Author(s)
•
•
•
Strafella, F.
•
Di Francesco, J.
•
Sadavoy, S.
•
André, P.
•
•
Bernard, J. P.
•
•
Facchini, A.
•
Hennemann, M.
•
Hill, T.
•
Könyves, V.
•
•
Motte, F.
•
Nguyen-Luong, Q.
•
Peretto, N.
•
Pestalozzi, M.
•
Polychroni, D.
•
•
Saraceno, P.
•
Schneider, N.
•
•
•
Ward-Thompson, D.
•
White, G. J.
DOI
Abstract
We report far-infrared Herschel observations obtained between 70 μm and 500 μm of two star-forming dusty condensations, [HKM99] B1-bS and [HKM99] B1-bN, in the B1 region of the Perseus star-forming cloud. In the western part of the Perseus cloud, B1-bS is the only source detected in all six PACS and SPIRE photometric bands, but it is not visible in the Spitzer map at 24 μm. B1-bN is clearly detected between 100 μm and 250 μm. We have fitted the spectral energy distributions of these sources to derive their physical properties, and find that a simple greybody model fails to reproduce the observed spectral energy distributions. At least a two-component model is required, consisting of a central source surrounded by a dusty envelope. The properties derived from the fit, however, suggest that the central source is not a Class 0 object. We then conclude that while B1-bS and B1-bN appear to be more evolved than a pre-stellar core, the best-fit models suggest that their central objects are younger than a Class 0 source. Hence, they may be good candidates to be examples of the first hydrostatic core phase. The projected distance between B1-bS and B1-bN is a few Jeans lengths. If their physical separation is close to this value, this pair would allow studying the mutual interactions between two forming stars at a very early stage of their evolution.

Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Appendices are available in electronic form at http://www.aanda.org

Volume
547
Start page
A54
Uri
Url
Issn Identifier
0004-6361
Ads BibCode
2012A&A...547A..54P
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

043FHSC.pdf

Description
Pdf editoriale
Size

1.07 MB

Format

Adobe PDF

Checksum (MD5)

831f5718451d9a8ec94bbfc13f717c3f