Embedded young stellar object candidates in the active star-forming complex w51: Mass function and spatial distribution

Miju Kang, John H Bieging, Matthew S. Povich, Youngung Lee

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

We present 737 candidate young stellar objects (YSOs) near the W51 giant molecular cloud over an area of 1.°25 × 1.°00 selected from Spitzer Space Telescope data. We use spectral energy distribution fits to identify YSOs and distinguish them from main-sequence (MS) or red giant stars, asymptotic giant branch stars, and background galaxies. Based on extinction of each YSO, we separate a total of 437 YSOs associated with the W51 region from the possible foreground sources. We identify 69 highly embedded Stage 0/I candidate YSOs in our field with masses >5 M Ȯ (corresponding to mid- to early-B MS spectral types), 46 of which are located in the central active star-forming regions of W51A and W51B. From the YSOs associated with W51, we find evidence for mass segregation showing that the most massive YSOs are concentrated on the W51 H II region complex. We find a variation in the spatial distribution of the mass function (MF) of YSOs in the mass range between 5 M Ȯ and 18 M Ȯ. The derived slopes of the MF are -1.26 and -2.36 in the active star-forming region and the outer region, respectively. The variation of the MF for YSOs embedded in the molecular cloud implies that the distribution of stellar masses in clusters depends on the local conditions in the parent molecular cloud.

Original languageEnglish (US)
Pages (from-to)83-93
Number of pages11
JournalAstrophysical Journal
Volume706
Issue number1
DOIs
StatePublished - 2009

Fingerprint

spatial distribution
distribution functions
stars
molecular clouds
red giant stars
Space Infrared Telescope Facility
asymptotic giant branch stars
H II regions
spectral energy distribution
stellar mass
young
extinction
slopes
galaxies
energy

Keywords

  • Hii regions
  • Infrared: ISM
  • ISM: individual (W51)
  • Stars: formation

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Embedded young stellar object candidates in the active star-forming complex w51 : Mass function and spatial distribution. / Kang, Miju; Bieging, John H; Povich, Matthew S.; Lee, Youngung.

In: Astrophysical Journal, Vol. 706, No. 1, 2009, p. 83-93.

Research output: Contribution to journalArticle

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