SUBARCSECOND IMAGING OF THE HIGH-MASS STAR-FORMING REGION ONSALA 1

被引：8

作者：

Su, Yu-Nung ^{[1
]}

Liu, Sheng-Yuan ^{[1
]}

Lim, Jeremy ^{[1
]}

机构：

[1] Acad Sinica, Inst Astron & Astrophys, Taipei 106, Taiwan

来源：

ASTROPHYSICAL JOURNAL | 2009年 / 698卷 / 02期

关键词：

H II regions; ISM: individual (Onsala 1); stars: formation; H-II REGIONS; MOLECULAR CLOUDS; OH MASERS; SUBMILLIMETER ARRAY; CONTINUUM EMISSION; WATER MASERS; OUTFLOW; CORES; DIFFERENTIATION; CLUSTERS;

D O I：

10.1088/0004-637X/698/2/1981

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report subarcsecond images of the high-mass star-forming region Onsala 1 (ON 1) made with the Submillimeter Array (SMA) at 0.85 mm and the Very Large Array (VLA) at 1.3 cm and 3.6 cm. ON 1 is one of the smallest ultracompact H II regions in the Galaxy and exhibits various star formation signposts. With our VLA and SMA observations, two new centimeter-wave sources and five submillimeter dust sources, respectively, within a field of similar to 5 '' (corresponding to a linear scale of 0.05 pc) are identified, indicating the multiplicity at the center of the ON 1 region. The dust and gas masses of these submillimeter sources are in the range of 0.8 to 6.4 M-circle dot. Among the five submillimeter dust sources, SMA2, with a dust and gas mass of 2.6 M-circle dot, demonstrates several star formation signatures, and hence likely represents an intermediate-mass (or even high-mass) star-forming core. Due to the low star formation efficiency of similar to 10%, we suggest that star formation in the ON 1 region will continue. For example, SMA4 and SMA5 are not associated with any star formation signatures and likely mark star formation cores at very early evolutionary stages.

引用

页码：1981 / 1988

页数：8

共 39 条

[1]

ANGLADA G, 1995, REV MEX AST ASTR, V1, P67

[2] Interstellar hydroxyl masers in the galaxy. I. The VLA survey [J].

Argon, AL ;

Reid, MJ ;

Menten, KM .

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2000, 129 (01) :159-227

[3] Massive star formation: nurture, not nature [J].

Bonnell, IA ;

Vine, SG ;

Bate, MR .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2004, 349 (02) :735-741

[4] H2O maser observations of candidate post-AGB stars and discovery of three high-velocity water sources [J].

Deacon, R. M. ;

Chapman, J. M. ;

Green, A. J. ;

Sevenster, M. N. .

ASTROPHYSICAL JOURNAL, 2007, 658 (02) :1096-1113

[5] Multifrequency, high-resolution radio recombination line observations of the massive star-forming region W49A [J].

DePree, CG ;

Mehringer, DM ;

Goss, WM .

ASTROPHYSICAL JOURNAL, 1997, 482 (01) :307-333

[6]

DOWNES D, 1979, ASTRON ASTROPHYS, V79, P233

[7] Proper motions of oh masers and magnetic fields in massive star-forming regions [J].

Fish, Vincent L. ;

Reid, Mark J. .

ASTROPHYSICAL JOURNAL, 2007, 670 (02) :1159-1172

[8] Expanded very large array observations of the 6035 mhz oh masers in on 1 [J].

Fish, Vincent L. .

ASTROPHYSICAL JOURNAL, 2007, 669 (02) :L81-L84

[9] Limits on radio continuum emission from a sample of candidate contracting starless cores [J].

Harvey, DWA ;

Wilner, DJ ;

Di Francesco, J ;

Lee, CW ;

Myers, PC ;

Williams, JP .

ASTRONOMICAL JOURNAL, 2002, 123 (06) :3325-3328

[10] The submillimeter array [J].

Ho, PTP ;

Moran, JM ;

Lo, KY .

ASTROPHYSICAL JOURNAL, 2004, 616 (01) :L1-L6

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