AAS 207th Meeting, 8-12 January 2006
Session 163 Star Formation Grab Bag I
Oral, Wednesday, 2:00-3:30pm, January 11, 2006, Wilson A/B

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[163.03] A Multi-Wavelength Study of Molecular Clouds and Starless Cores

S.L. Schnee, A.A. Goodman (Harvard-Smithsonian CfA)

The physical properties of star-forming regions are best studied with a suite of measurements at a variety of wavelengths. My thesis is centered on combining several maps of the emission and/or extinction from dust with molecular line transition on scales as large as that of entire molecular clouds and as small as that of individual star-forming cores.

As part of the COMPLETE Survey of Star-Forming Regions we have made a new set of dust temperature and column density maps for the Perseus, Ophiuchus and Serpens molecular clouds. Using the newly recalibrated IRAS data (IRIS) and 2MASS maps, we have determined the conversion from 100 micron optical depth to visual extinction, and found that this conversion is significantly different between clouds. In addition, we show that using IRAS maps to determine the column density of dust results in significant errors for AV > 1 due to temperature variations along the line of sight. The observed scatter between column density derived from pairs of emission maps and column density derived from the NIR colors of background stars can be reproduced without the inclusion of emission from transiently heated dust grains and without including the effects of variable dust emission properties.

Using SCUBA and MAMBO maps of TMC-1C, a starless core in Taurus, we have mapped the dust temperature, column density, and emissivity spectral index at ~14 arcsecond resolution. The density profile is consistent with that of a Bonnor-Ebert sphere, and the temperature varies from 7 to 12 K. By combining the dust emission maps with molecular line maps we show that TMC-1C is out of virial equilibrium and contracting at a rate slower than the sound speed.

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