NANTEN Observations of Dense Cores in the Corona Australis Molecular Cloud

Abstract

We carried out a C18O survey for dense molecular cores in the Corona Australis (CrA) molecular cloud with the NANTEN telescope. We observed 2.2 deg2 at a 2′ grid spacing with a 2′.7 beam, and 1980 positions were observed. We identified 8 C18O cores, whose typical line width, average column density, radius, mass, and average number density were 0.66 km s-1, 1.1×1022 cm-2, 0.13 pc, 18 M⊙ , and 1.4 × 104 cm-3, respectively. We found that Δ Vcomp, 〈 N(H2)〉, R, M, and n(H2) become larger along with an increase in the star-formation activity, whereas the ratio Mvir/M becomes smaller. A comparison of the present cores with those in Chamaeleon, Lupus, Ophiuchus, Taurus, and L 1333 indicates that star-forming cores tend to have a high column density, as well as a smaller Mvir/M ratio.