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arXiv · 1409.7143

ALMA Observations of the IRDC Clump G34.43+00.24 MM3: 278 GHz Class I Methanol Masers

Takahiro Yanagida·Takeshi Sakai·Tomoya Hirota·Nami Sakai·Jonathan B. Foster·Patricio Sanhueza·James M. Jackson·Kenji Furuya·Yuri Aikawa·Satoshi Yamamoto
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Abstract

We have observed a molecular clump (MM3) associated with the infrared dark cloud G34.43+00.24 in the CH3OH J_K=9_{-1}--8_0 E, 5_0-4_0 E, and 5_{-1}-4_{-1} E lines at sub-arcsecond resolution by using the Atacama Large Millimeter/submillimeter Array. By comparing the CH3OH J_K=9_{-1}-8_0 E emission with the CH3OH 5_0-4_0 E and 5_{-1}-4_{-1} E emission, we have found that the CH3OH J_K=9_{-1}-8_0 E emission is masing. We have clearly shown that the CH3OH J_K=9_{-1}-8_0 masers arise from the post shocked gas in the interacting regions between the outflows and ambient dense gas. Toward the strongest peak of the CH3OH maser emission, SiO J=6-5 emission is very weak. This indicates that the CH3OH maser emission traces relatively old shocks or weak shocks.

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Takahiro Yanagida, Takeshi Sakai, Tomoya Hirota, Nami Sakai, Jonathan B. Foster, Patricio Sanhueza, James M. Jackson, Kenji Furuya, Yuri Aikawa, Satoshi Yamamoto. 2014-09-25. ALMA Observations of the IRDC Clump G34.43+00.24 MM3: 278 GHz Class I Methanol Masers. https://doi.org/10.1088/2041-8205/794/1/l10

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