arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1201.0696astro-ph.GA
收藏

TMC1碳同位素分馏和贫化

Carbon isotope fractionation and depletion in TMC1

H. S. Liszt, L. M. Ziurys

备注：
Accepted for publication in The Astrophysical Journal (mail journal)
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

12 C/13 C同位素丰度异常长期以来一直被预测为CO以外的分子的气相化学，最近在金牛座分子云中观察到几个含有一个以上碳原子的物种，即CCH，CCS，CCCS和HC $_3$ N。在这里，我们的工作，以确定这些同位素异常是否实际上是由于预测的13 C+离子在富氧的光屏蔽致密气体中的耗尽，或从一些其他更特殊的机制或机制。我们用ARO 12 m望远镜在金牛座的三个位置（TMC 1、L1527和氨峰）观测到HNC、CS和\HH CS的碳、硫和氮同位素的$λ$ 3 mm发射。我们在观测中没有发现12 C/13 C异常的证据。虽然C+池可能在13 C中耗尽，但13 C并没有在CO之外的一般碳池中耗尽，CO可能主要以C^0的形式存在。所观察到的同位素丰度异常是那些发现它们的物种所特有的。

英文摘要：

12C/13C isotopologue abundance anomalies have long been predicted for gas-phase chemistry in molecules other than CO and have recently been observed in the Taurus molecular cloud in several species hosting more than one carbon atom, i.e. CCH, CCS, CCCS and HC$_3$N. Here we work to ascertain whether these isotopologic anomalies actually result from the predicted depletion of the 13C+ ion in an oxygen-rich optically-shielded dense gas, or from some other more particular mechanism or mechanisms. We observed $λ$3mm emission from carbon, sulfur and nitrogen-bearing isotopologues of HNC, CS and \HH CS at three positions in Taurus(TMC1, L1527 and the ammonia peak) using the ARO 12m telescope. We saw no evidence of 12C/13C anomalies in our observations. Although the pool of C+ is likely to be depleted in 13C 13C is not depleted in the general pool of carbon outside CO, which probably exists mostly in the form of C^0. The observed isotopologic abundance anomalies are peculiar to those species in which they are found.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑