The BLAST Survey of the Vela Molecular Cloud: Dynamical Properties of the Dense Cores in Vela-D

Abstract

The Vela-D region, according to the nomenclature given by Murphy & May (1991), of the star forming complex known as the Vela Molecular Ridge (VMR), has been recently analyzed in details by Olmi et al. (2009), who studied the physical properties of 141 pre- and proto-stellar cold dust cores, detected by the ``Balloon-borne Large-Aperture Submillimeter Telescope'' (BLAST) during a much larger (55 sq. degree) Galactic Plane survey encompassing the whole VMR. This survey's primary goal was to identify the coldest, dense dust cores possibly associated with the earliest phases of star formation. In this work, the dynamical state of the Vela-D cores is analyzed. Comparison to dynamical masses of a sub-sample of the Vela-D cores estimated from the 13CO survey of Elia et al. (2007), is complicated by the fact that the 13CO linewidths are likely to trace the lower density intercore material, in addition to the dense gas associated with the compact cores observed by BLAST. In fact, the total internal pressure of these cores, if estimated using the 13CO linewidths, appears to be higher than the cloud ambient pressure. If this were the case, then self-gravity and surface pressure would be insufficient to bind these cores and an additional source of external confinement (e.g., magnetic field pressure) would be required. However, if one attempts to scale down the 13CO linewidths, according to the observations of high-density tracers in a small sample of sources, then most proto-stellar cores would result effectively gravitationally bound.

This paper has 12 pages and 6 figures. Accepted for publication by the Astrophysical Journal on July 19, 2010

References in corpus (12)

• Theory of Star Formation
• The Mass Distribution and Lifetime of Prestellar Cores in Perseus, Serpens, and Ophiuchus
• The Nature of the Dense Core Population in the Pipe Nebula: Thermal Cores Under Pressure
• Comparing Star Formation on Large Scales in the c2d Legacy Clouds: Bolocam 1.1 mm Dust Continuum Surveys of Serpens, Perseus, and Ophiuchus
• The Balloon-borne Large Aperture Submillimeter Telescope: BLAST
• BLAST: The Mass Function, Lifetimes, and Properties of Intermediate Mass Cores from a 50 Square Degree Submillimeter Galactic Survey in Vela (l = ~265)
• The nature of the dense core population in the Pipe Nebula: A survey of NH3, CCS, and HC5N molecular line emission
• The nature of the dense core population in the pipe nebula: core and cloud kinematics from C18O observations
• The BLAST Survey of the Vela Molecular Cloud: Physical Properties of the Dense Cores in Vela-D
• Mapping molecular emission in Vela Molecular Ridge Cloud D
• Star formation in the Vela Molecular Ridge. Large scale mapping of cloud D in the mm continuum
• Testing circumstellar disk lifetimes in young embedded clusters associated with the Vela Molecular Ridge

Cited by in corpus (6)

• The first Hi-GAL observations of the outer Galaxy: a look to star formation in the third Galactic quadrant in the longitude range 216.5 < l < 225.5
• Herschel-ATLAS: Statistical Properties of Galactic Cirrus in the GAMA-9 Hour Science Demonstration Phase Field
• Spitzer-IRAC survey of molecular jets in Vela-D
• Cluster aggregates surrounding Pismis 5 in the Vela Molecular Ridge
• A spectral line survey of the starless and proto-stellar cores detected by BLAST toward the Vela-D molecular cloud
• Experimental and Numerical Studies of the Collapse of Dense Clouds Induced by Herbig-Haro Stellar Jets