IRAS 23133+6050云核的观测研究  

The Observations and Researches of Molecular Cloud Core Associated with IRAS 23133+6050

作　　者：王敏[1] 杨戟[1] 耿韬[1] 朱留斌[1] 

机构地区：[1]中国科学院紫金山天文台,南京210008

出　　处：《天文学报》2007年第3期289-301,共13页Acta Astronomica Sinica

基　　金：国家自然科学基金(编号10133020和10373025)资助

摘　　要：利用紫金山天文台青海观测站13.7 m毫米波望远镜对IRAS 23133+6050云核进行^(13)CO、C^(18)O、HCO+(J=1-0)谱线观测.^(13)CO、C^(18)O、HCO+分子谱线辐射所对应的云核直径分别为4.0pc、2.1 pc、2.3 pc,质量分别为2.7×10~3M_⊙、0.9×10~3M_⊙、2.3×10~3M_⊙,气体平均密度分别为2.7×10~3 cm^(-3)、5.1×10~3 cm^(-3)、4.6×10~3cm^(-3).用幂律模型n(r)～^(-P)的形式分析了云核的密度分布,得到的指数p分别为1.75、1.56、1.48.分析发现,密度结构谱指数从云核的外部向内部逐渐变平坦.观测得到HCO^+丰度为4.6×10^(-10),比暗云低一个数量级以上,比巨分子云也略低,而^(13)CO、C^(18)O的相对丰度比X_(13/18)为12.2,这与暗云11.8和巨分子云9.0～15.6的情况一致.该区域发现存在^(13)CO双极外流.由IRAS远红外光度和维里质量得到的光度质量比,分别为18.1,51.1、21.2.This paper reports ^13CO, C^180, HCO^＋（J=1-0） line observations toward IRAS 23133＋6050 with the 13.7 m millimeter-wave telescope at Qinghai Station of PMO. The sizes of the cores corresponding to ^13CO, C^18O, HCO^＋ line emissions are 4.0pc, 2.1pc, 2.3pc; the virial masses are 2.7×10^3M⊙, 0.9×10^3M⊙, 2.3×10^3M⊙; the volume densities of H2 are 2.7×10^3 cm^-3, 5.1×10^3 cm^-3, 4.6×10^3 cm^-3. Using a power-law function of n（r）～r^-p, the spatial density structure of the core has been studied. The indices are 1.75, 1.56, 1.48 for ^13CO, C^18O, HCO^＋. The indices become flat gradually from the outside to the inner core. The abundance of HCO^＋ is 4.6×10^-10, 1 magnitude less than the value of DMCs, slightly less than the value of GMCs. The abundance ratio of ^13CO/C^18O is 12.2, comparable with the value of 11.8 for DMCs, and 9.0～15.6 for GMCs. A bipolar ^13CO molecular outflow is found toward this area. The abundance of HCO^＋ in the area of outflow is not higher than other area. The ratios of the IRAS FIR luminosity to virial mass are 18.1, 51.1 and 21.2 respectively.

关 键 词：恒星 形成 星际介质 谱线 星际介质 丰度 

分 类 号：P144[天文地球—天体物理]