摘要
利用紫金山天文台青海站的 13.7 m毫米波望远镜,对 Orion A分子云中的 OMC-3区域,进行了较高分辨率的13CO(J=1-0)和C18O(J=1-0)分子辐射的成图观测.给出了该分子云中13CO和 C18O云核分布的整体结构和平均物理参数.观测发现,该分子云的13CO和 C18O的云核中心分别与最年轻的天体-Class 0类源 MMSI, MMS4,MMS6和MMS7,MMS8;MMS9成协.此外,通过分析OMC-3整个区域的速度场结构,发现沿 C18O和13CO云核方向从南到北有一个~ 1.7km/s的速度场梯度,而分子云的红、蓝移团块则分别趋于云的北部和南部.并对OMC-3区的恒星形成特征进行了讨论.
CO (J = 1 - 0) and C18O (J = 1 - 0) emissions of the OMC-3 in the Orion A molecular cloud were mapped with the 13.7 m millimeter wave telescope of Purple Mountain Observatory using a higher spatial resolution. The overall structure of the cloud and the average physical parameters of all the 13CO (J = 1 - 0) and C18O (J = 1 - 0) cores are derived. We find that the cores are well associated with the youngest objects - class 0 sources: MMS1, MMS4, MMS6 with the 13CO core centers and MMS7, MMSS, MMS9 with the C18O core centers. The velocity structure is also analyzed for the whole OMC-3 region. There is a ~ 1.7 km/s velocity gradient from south to north connecting the 13CO (J = 1 - 0) and C18O (J = 1 - 0) cores. And the redshifted clumps are consistently to the north, and the blushifted clumps, to the south of OMC-3. Star formation in the region is also discussed.
基金
国家自然科学基金
中国科学院射电天文联合实验室资助