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arXiv · astro-ph/0609625

HOCO+ toward the Galactic Center

Shuji Deguchi·Atsushi Miyazaki·Young Chol Minh
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Abstract

We have identified a weak thermal line U42.767, which has been detected only in the directions toward Sgr A and Sgr B2, as the HOCO+ 2_{02}--1_{01} transition. Because of the proximity of this line to the SiO maser line at 42.821 GHz (J=1-0 v=2),it was observable simultaneously in the ~43 GHz SiO maser searches at Nobeyama. From the past data of SiO maser surveys of infrared objects in the Galactic center, we created a map of emission distribution of HOCO+ in the Sgr A molecular cloud as well as maps of the 29SiO J=1-0 v=0 thermal emission and H53alpha emission. The emission distribution of HOCO+ was quite similar to the distribution of 29SiO emission. It suggests that the enhancement of the HOCO+ abundance in the galactic center is induced by shock activities which release the CO2 molecules frozen on grains into gases.

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Shuji Deguchi, Atsushi Miyazaki, Young Chol Minh. 2006-09-22. HOCO+ toward the Galactic Center. https://doi.org/10.1093/pasj%2F58.6.979

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