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arXiv · 1909.00528

Survey Observation of CH$_3$NH$_2$ and Its Formation Process

Taiki Suzuki·Liton Majumdar·Kazuki Tokuda·Harumi Minamoto·Masatoshi Ohishi·Masao Saito·Tomoya Hirota·Hideko Nomura·Yoko Oya
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Abstract

We present the observational result of a glycine precursor, methylamine (CH$_3$NH$_2$), together with methanol (CH$_3$OH) and methanimine (CH$_2$NH) towards high-mass star-forming regions, NGC6334I, G10.47+0.03, G31.41+0.3, and W51~e1/e2 using ALMA. The molecular abundances toward these sources were derived using the rotational diagram method and compared with our state-of-the-art chemical model. We found that the observed ratio of "CH$_3$NH$_2$/CH$_3$OH" is in between 0.11 and 2.2. We also found that the observed "CH$_3$NH$_2$/CH$_3$OH" ratio agrees well with our chemical model by considering the formation of CH$_3$NH$_2$ on the grain surface via hydrogenation process to HCN. This result clearly shows the importance of hydrogenation processes to form CH$_3$NH$_2$. NGC63343I MM3, where CH$_3$NH$_2$ was not detected in this study and showed "CH$_3$NH$_2$/CH$_3$OH" ratio of less than 0.02, is clearly distinguished from the other cores.

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Taiki Suzuki, Liton Majumdar, Kazuki Tokuda, Harumi Minamoto, Masatoshi Ohishi, Masao Saito, Tomoya Hirota, Hideko Nomura, Yoko Oya. 2019-09-02. Survey Observation of CH$_3$NH$_2$ and Its Formation Process. https://arxiv.org/abs/1909.00528

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