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arXiv · 0802.4132

Molecular Line Observations of the SiO Maser Source IRAS 19312+1950

Jun-ichi Nakashima·Shuji Deguchi·Hiroshi Imai·Athol Kemball
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Abstract

IRAS 19312+1950 is a unique SiO maser source, exhibiting a rich set of molecular radio lines, although SiO maser sources are usually identified as oxygen-rich evolved stars, in which chemistry is relatively simple comparing with carbon-rich environments. The rich chemistry of IRAS 19312+1950 has raised a problem in circumstellar chemistry if this object is really an oxygen-rich evolved star, but its evolutional status is still controversial. In this paper, we briefly review the previous observations of IRAS 19312+1950, as well as presenting preliminary results of recent VLBI observations in maser lines.

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Jun-ichi Nakashima, Shuji Deguchi, Hiroshi Imai, Athol Kemball. 2008-02-28. Molecular Line Observations of the SiO Maser Source IRAS 19312+1950. https://doi.org/10.1017/s1743921308021467

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