摘要
利用ＶＬＡ的观测，我们在猎户座分子云区，发现了１１个小质量分子云浓核。它们的平均有效半径为０．０３ｐｃ，平均质量为３．５Ｍ⊙，分布在呈丝状母云南北走向的轴线上。在浓核区３＇的范围内，测到有５ｋｍｓ－１ｐｃ－１的速度梯度，一个可能的解释是这个核区的慢速转旋。根据我们的ＮＨ３（１，１）的观测资料，并与尘埃的毫米波连续辐射和红外辐射比较，我们认为这个区域的大部浓核是还没有星核的年轻分子云核，正处于热动能与自引力的平衡阶段。
Eleven low-mass cores are found in the Orion Molecular Cloud 2 from VLA observations of the line emission of NH3(1,1). They are perhaps clumps prior to gravitational collapse with average radius of 0.03pc and mass of 3.5 M⊙, distributed along the central axes of filaments in the NS direction. We find a velocity gradient of～5 km s-1 pc-1 in the declination direction within a 3'region. Based on our NH3(1,1) observations and compared with dust continuum emission at millimeter wavelength as well as in the infrared,we suggest that most of these dense cores are probably protosteller condensations,not yet containing stellar cores, but are self-gravitating systems in thermodynamical equilibrium.
基金
攀登计划资助
