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arXiv · 1610.03942

Discovery of a Hot Corino in the Bok Globule B335

Muneaki Imai·Nami Sakai·Yoko Oya·Ana López-Sepulcre·Yoshimasa Watanabe·Cecilia Ceccarelli·Bertrand Lefloch·Emmanuel Caux·Charlotte Vastel·Claudine Kahane·Takeshi Sakai·Tomoya Hirota·Yuri Aikawa·Satoshi Yamamoto
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Abstract

We report the first evidence of a hot corino in a Bok globule. This is based on the ALMA observations in the 1.2 mm band toward the low-mass Class 0 protostar IRAS 19347+0727 in B335. Saturated complex organic molecules (COMs), CH$_3$CHO, HCOOCH$_3$, and NH$_2$CHO, are detected in a compact region within a few 10 au around the protostar. Additionally, CH$_3$OCH$_3$, C$_2$H$_5$OH, C$_2$H$_5$CN, and CH$_3$COCH$_3$ are tentatively detected. Carbon-chain related molecules, CCH and c-C$_3$H$_2$, are also found in this source, whose distributions are extended over a few 100 au scale. On the other hand, sulfur-bearing molecules CS, SO, and SO$_2$, have both compact and extended components. Fractional abundances of the COMs relative to H$_2$ are found to be comparable to those in known hot-corino sources. Though the COMs lines are as broad as 5-8 km s$^{-1}$, they do not show obvious rotation motion in the present observation. Thus, the COMs mainly exist in a structure whose distribution is much smaller than the synthesized beam (0."58 x 0."52).

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Muneaki Imai, Nami Sakai, Yoko Oya, Ana López-Sepulcre, Yoshimasa Watanabe, Cecilia Ceccarelli, Bertrand Lefloch, Emmanuel Caux, Charlotte Vastel, Claudine Kahane, Takeshi Sakai, Tomoya Hirota, Yuri Aikawa, Satoshi Yamamoto. 2016-10-13. Discovery of a Hot Corino in the Bok Globule B335. https://doi.org/10.3847/2041-8205%2F830%2F2%2Fl37

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