An Observational Study of the Molecular Cloud Core Toward IRAS 23133+6050☆☆☆

Abstract This paper reports 13 CO, C 18 O, HCO + (J = 1−0) spectral observations toward IRAS 23133+6050 with the 13.7 m millimeter-wave telescope at Qinghai Station of PMO. Corresponding to the 13 CO, C 18 O, HCO + line emissions, the size of the observed molecular cloud core is 4.0 pc, 2.1 pc and 2.3 pc, the virial mass is 2.7 × 10 3 M ⊙ , 0.9 × 10 3 M ⊙ and 2.3 × 10 3 M ⊙ , and the volume density of H 2 is 2.7 × 10 3  cm −3 , 5.1 × 10 3  cm −3 and 4.6 × 10 3  cm −3 , respectively. Using the power-law function n ( r ) ∼ r − p , the spatial density distribution of the cloud core was analyzed, the obtained exponent p is respectively 1.75, 1.56 and 1.48 for the 13 CO, C 18 O and HCO + cores, and it is found that the density distribution becomes gradually flatter from the outer region to the inner region of the core. The HCO + abundance is 4.6 × 10 −10 , one order of magnitude less than the value for dark clouds, and slightly less than that for giant molecular clouds. The 13 CO/C 18 O relative abundance ratio is 12.2, comparable with the value 11.8 for dark clouds, and the value 9.0 ∼ 15.6 for giant molecular clouds. A 13 CO bipolar outflow is found in this region. The IRAS far-infrared luminosity and the virial masses give the luminosity-mass ratios 18.1, 51.1 and 21.2 from the three lines.