Other
Scientific paper
Dec 2001
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001aas...199.0402c&link_type=abstract
American Astronomical Society, 199th AAS Meeting, #04.02; Bulletin of the American Astronomical Society, Vol. 33, p.1306
Other
Scientific paper
We have carried out a survey of optically-selected dark clouds using the bolometer array SCUBA at 850 μ m on the JCMT\@. The survey covers a total of 0.5 square degrees and is unbiased with reference to size, star formation activity, or the presence of infrared emission. Several new protostars and starless cores have been discovered; the protostars are confirmed through the detection of their accompanying outflows in CO(2--1) emission. The survey is believed to be complete for Class 0 and Class I protostars, and yields two important results regarding the lifetimes of these phases. First, the ratio of Class 0 to Class I protostars in the sample is roughly unity, very different from the 1:10 ratio that has been observed for the ρ Ophiuchi star-forming region. Assuming star formation to be a homogeneous process in the dark clouds this implies that the Class 0 lifetime is similar to the Class I phase, which from infrared surveys has been established to be ~ 2 x 105 yr, and suggests there is no rapid initial accretion phase in these objects. Second, the number of starless cores is approximately twice that of the total number of protostars, indicating a starless core lifetime of ~ 8 x 105 yr. A comparison of these statistical lifetimes with those measured for other star-forming regions indicates that the details of the star formation process is highly dependent on the local environment. Furthermore, and most importantly, this survey implies that the starless cores are very short-lived and survive only one or two free-fall times, which in turn implies that their evolution cannot be controlled by magnetic processes.
Chandler Claire J.
Richer John S.
Visser Anja E.
No associations
LandOfFree
Star Formation in Lynds Dark Clouds does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Star Formation in Lynds Dark Clouds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Star Formation in Lynds Dark Clouds will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1228188