论文标题
对金牛座分子云中CH2DOH朝向无星和prestellar核心的调查
A Survey of CH2DOH Towards Starless and Prestellar Cores in the Taurus Molecular Cloud
论文作者
论文摘要
最近的观察结果表明，有机分子普遍存在无星和prestellar核心。在无星阶段，这些分子的剥离尚未得到充分研究。仅在几个经过充分研究，密集和进化的prestell核心（例如L1544，l183）中观察到了对单人列出的甲醇（ch $ _2 $ doh）的已发表观察结果。由于据信在这种冷阶段的气相甲醇的形成是通过从冰上谷物表面解吸而发生的，因此观察Ch $ _2 $ doh的观察可能是对粉尘粒冰分中氘级分的探测。我们对金牛座分子云的B10区域中的12个无星和prestellar核心进行了系统的调查。在[Ch $ _2 $ doh]/[Ch $ _3 $ OH]中检测到十二个内核中的9个核心，范围从$ <0.04 $到$ 0.23^{+0.12} _ { - 0.06} $，中间值为$ 0.11 $。与检测到的来源相比，未检测到的来源往往具有更大的病毒参数和更大的甲醇线宽。这项调查的结果表明，在无星相期间，有机分子（例如甲醇）的氘分馏可能比以前认为的更容易检测到。
Recent observations indicate that organic molecules are prevalent towards starless and prestellar cores. Deuteration of these molecules has not been well-studied during the starless phase. Published observations of singly-deuterated methanol, CH$_2$DOH, have only been observed in a couple of well-studied, dense and evolved prestellar cores (e.g. L1544, L183). Since the formation of gas-phase methanol during this cold phase is believed to occur via desorption from the icy grain surfaces, observations of CH$_2$DOH may be useful as a probe of the deuterium fraction in the ice mantles of dust grains. We present a systematic survey of CH$_2$DOH towards 12 starless and prestellar cores in the B10 region of the Taurus Molecular Cloud. Nine of the twelve cores are detected with [CH$_2$DOH]/[CH$_3$OH] ranging from $< 0.04$ to $0.23^{+0.12}_{-0.06}$ with a median value of $0.11$. Sources not detected tend to have larger virial parameters and larger methanol linewidths than detected sources. The results of this survey indicate that deuterium fractionation of organic molecules, such as methanol, during the starless phase may be more easily detectable than previously thought.
