MAPPING STUDY OF 71 PLANCK COLD CLUMPS IN THE TAURUS, PERSEUS, AND CALIFORNIA COMPLEXES

Abstract

A mapping study of 71 Planck cold clumps was made with 12CO(1-0), 13CO(1-0), and C18O(1-0) lines at the 13.7 m telescope of Purple Mountain Observatory. For all the clumps, 12CO(1-0) and 13CO(1-0) emissions were detected, while for 55 of them, C18O(1-0) emissions were detected. Of the 71 Clumps, 34 are in the Taurus Complex, 24 in the California Complex, and 13 are in the Perseus Complex. In the 76 velocity components, 38 cores are found in 27 clumps; 19 of these cores are in the Taurus Complex, 16 in the California Complex, and 3 in the Perseus Complex. We acquired V lsr, TA and FWHM of lines. Physical parameters including T ex, , σTherm, σNT, and σ3D were calculated. Generally, the cores are of T ex = 2-16 K, cm–2, and σ3D = 0.2-1.0 km s–1. In the Taurus Complex, the cores are less dense on average and have smaller σTherm than the cores in the Perseus and California Complexes. Two of the three cores in the Perseus Complex are revealed to have larger T ex, , and σ3D than the mean values in the other two regions. Most of the cores have σNT larger than σTherm, suggesting a dominance of turbulence in our cores. The majority of the cores have M vir/M LTE 1, which indicates these cores are not bound and will disperse. By comparing our results with the dust properties revealed by the Planck Early Release Cold Cores Catalog, we investigated the coupling of gas and dust components. We found that most of the cores have dust temperatures higher than their gas temperatures. The stellar objects associated with our sources were checked and 90% of the cores were found to be starless.