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arXiv · 1105.0081

Detection of Two Carbon-Chain-Rich Cores; CB130-3 and L673-SMM4

Tomoya Hirota·Takeshi Sakai·Nami Sakai·Satoshi Yamamoto
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Abstract

We have found two dense cores, CB130-3 and L673-SMM4, where the carbon-chain molecules are extremely abundant relative to NH$_{3}$, during a survey observation of radio emission lines of CCS, HC$_{3}$N, HC$_{5}$N, and NH$_{3}$ toward dark cloud cores. Judging from the low NH$_{3}$/CCS ratios, they are possible candidates for "Carbon-Chain--Producing Regions (CCPRs)" recognized as chemically young dark cloud cores. The deuterium fractionation ratios DNC/HN$^{13}$C in CB130-3 and L673-SMM4 are found to be 1.28$^{+0.27}_{-0.05}$ and 1.96$^{+0.32}_{-0.01}$, respectively, which are comparable to or slightly higher than those in CCPRs found previously. We suggest that the dense cores of CB130-3 and L673-SMM4 are analogous to CCPRs but their chemical evolutionary phase would be slightly older than those of the dense cores in the Taurus region.

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Tomoya Hirota, Takeshi Sakai, Nami Sakai, Satoshi Yamamoto. 2011-04-30. Detection of Two Carbon-Chain-Rich Cores; CB130-3 and L673-SMM4. https://doi.org/10.1088/0004-637x/736/1/4

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