A multi-wavelength census of star formation activity in the young embedded cluster around Serpens/G3-G6

被引:26
作者
Djupvik, A. A.
Andre, Ph.
Bontemps, S.
Motte, F.
Olofsson, G.
Galfalk, M.
Floren, H. -G.
机构
[1] Nord Opt Telescope, Santa Cruz de La Palma 38700, Spain
[2] CEA Saclay, Serv Astrophys, DAPNIA, DSM, F-91191 Gif Sur Yvette, France
[3] Observ Bordeaux, F-33270 Floirac, France
[4] Stockholm Observ, S-10691 Stockholm, Sweden
[5] Univ Paris 07, CNRS, UMR 7158, CEA,AIM, F-75221 Paris 05, France
基金
巴西圣保罗研究基金会;
关键词
stars : formation; stars : pre-main sequence; stars : luminosity function; mass function; ISM : jets and outflows; stars; low-mass; brown dwarfs;
D O I
10.1051/0004-6361:20065533
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Aims. The aim of this paper is to characterise the star formation activity in the poorly studied embedded cluster Serpens/G3-G6, located similar to 45' ( 3 pc) to the south of the Serpens Cloud Core, and to determine the luminosity and mass functions of its population of Young Stellar Objects ( YSOs). Methods. Multi-wavelength broadband photometry was obtained to sample the near and mid-IR spectral energy distributions to separate YSOs from field stars and classify the YSO evolutionary stage. ISOCAM mapping in the two filters LW2 ( 5-8.5 mu m) and LW3 ( 12-18 mu m) of a 19' x 16' field was combined with JHK(S) data from 2MASS, K-S data from Arnica/NOT, and L' data from SIRCA/NOT. Continuum emission at 1.3 mm ( IRAM) and 3.6 cm ( VLA) was mapped to study the cloud structure and the coldest/youngest sources. Deep narrow band imaging at the 2.12 mu m S ( 1) line of H-2 from NOTCam/NOT was obtained to search for signs of bipolar outflows. Results. We have strong evidence for a stellar population of 31 Class II sources, 5 flat-spectrum sources, 5 Class I sources, and two Class 0 sources. Our method does not sample the Class III sources. The cloud is composed of two main dense clumps aligned along a ridge over similar to 0.5 pc plus a starless core coinciding with absorption features seen in the ISOCAM maps. We find two S-shaped bipolar collimated flows embedded in the NE clump, and propose the two driving sources to be a Class 0 candidate ( MMS3) and a double Class I ( MMS2). For the Class II population we find a best age of similar to. 2 Myr and compatibility with recent Initial Mass Functions ( IMFs) by comparing the observed Class II luminosity function ( LF), which is complete to 0.08 L-circle dot, to various model LFs with different star formation scenarios and input IMFs.
引用
收藏
页码:789 / 803
页数:15
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