Star formation in small globules - Bart Bok was correct

Journal Article · Sat Dec 01 04:00:00 EST 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/185891· OSTI ID:6261448

Yun, J L; Clemens, D P ^[1]

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1. Boston Univ., MA (USA)

A large sample of optically selected, small molecular clouds (Bok globules) has been probed using IRAS coadded images to search for associated young stellar objects. The IRAS images were examined for point sources located within the boundaries of the optical and infrared extents of 248 clouds. A total of 57 of the globules (23 percent of the sample) show evidence for associated point sources. From a comparison of the 12- and 25-micron fluxes of these objects, a distribution of spectral indices consistent with the presence of circumstellar dust is found. Similar analysis of other point sources within the IRAS images, but far from the globule boundaries, shows only normal stellar spectral indices. All young stars more massive than 0.7 solar masses were likely found. However, extrapolation of a Miller-Scalo (1979) initial mass function to the hydrogen-burning limit indicates that only about 20 percent of the total number of stars were found. It is therefore likely that almost every Bok globule harbors a young star. The inferred star formation efficiency is about 6 percent, again based on the Miller-Scalo initial mass function. Interestingly, this is the best test in 43 years of the conjecture made by Bok, that dust globules could represent the earliest stage of star formation. His conjecture was correct. 19 refs.

• OSTI ID: 6261448
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 365; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COORDINATES
COSMIC GASES
DETECTION
ELECTROMAGNETIC RADIATION
FLUIDS
GASES
HYDROGEN BURNING
IMAGES
INFRARED RADIATION
INTERSTELLAR SPACE
LUMINOSITY
MASS
NEBULAE
OPTICAL PROPERTIES
PHOTOMETRY
PHYSICAL PROPERTIES
POINT SOURCES
PROTOSTARS
RADIATION SOURCES
RADIATIONS
SATELLITES
SPACE
STAR BURNING
STAR EVOLUTION