COMPARATIVE-ANALYSIS OF THE FAR-INFRARED AND (CO)-C-13 (J=0-1) EMISSIONS OF THE TAURUS COMPLEX

IRAS images of the Taurus complex are presented. The map of the cold IR emission, emission with a low 60-100 mum color ratio, is dominated by a spectacular network of filament-like structures, with a typical width equal to approximately 1 pc, including almost all star-forming regions. Comparable in angular resolution with the IRAS data, the velocity-integrated (CO)-C-13 (J = 1-0) molecular map of the Taurus region obtained by Fukui & Mizuno (1991) at Nagoya (Japan) is strongly correlated with the cold component of the IR emission maps. We have analyzed the correlation inside small boxes whose size is 0.9 pc. The slope of regression line between the two emissions goes from 0.8 to 1.4 MJy sr-1 K-1 km-1 s. Moreover, slope gradients are visible within given structures. Independent conversions of the (CO)-C-13 (J = 1-0) and the cold component emissions into H-2 column densities show that the (CO)-C-13 and cold component emitting volumes are roughly comparable. This could explain the correlation and the limited range of values found for the regression line slope between the two emissions. The slope variations of a factor of approximately 2 with distances as small as our analysis box, i.e., 0.9 pc, should result from different physical properties of the dust or differences in (CO)-C-13 abundance, excitation, and radiation transfer conditions.