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arXiv · 1309.7061

The Environment around the Young Massive Star Cluster RSGC 1 and HESS J1837-069

Yutaka Fujita·Hiroyuki Nakanishi·Erik Muller·Naoto Kobayashi·Masao Saito·Chikako Yasui·Hiroki Kikuchi·Keigo Yoshinaga
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Abstract

We report on Mopra observations toward the young massive star cluster RSGC 1, adjoined by, and possibly associated with the gamma-ray source HESS J1837-069. We measure the CO (J=1-0) distribution around the cluster and gamma-ray source, and find that the cluster is slightly higher than the velocity ranges associated with the Crux-Scutum arm. We reveal the cluster is associated with much less molecular gas compared with other young massive clusters in the Galaxy, Westerlund 1 (Wd 1) and 2 (Wd 2), which also radiate gamma-rays. We find no other structures that would otherwise indicate the action of supernova remnants, and due to the lack of material which may form gamma-rays by hadronic interaction, we conclude that the gamma-rays detected from HESS J1837-069 are not created through proton-proton interactions, and may more plausibly originate from the pulsar that was recently found near RSGC 1.

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Yutaka Fujita, Hiroyuki Nakanishi, Erik Muller, Naoto Kobayashi, Masao Saito, Chikako Yasui, Hiroki Kikuchi, Keigo Yoshinaga. 2013-09-26. The Environment around the Young Massive Star Cluster RSGC 1 and HESS J1837-069. https://doi.org/10.1093/pasj%2Fpst020

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