Journal of Astronomy and Space Sciences

The Korean Space Science Society (한국우주과학회)
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Observations of the CH3OH 42-51 E Line Toward the Sgr B2 Region

  • Received : 2011.01.20
  • Accepted : 2011.02.11
  • Published : 2011.03.15
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Abstract

The $CH_3OH$ $4_2-5_1$ E transition was observed toward the Sgr B2 region, including the Principal Cloud and its surroundings. This methanol transition shows an extended emission along the 2'N cloud, which is believed to be colliding with the Principal Cloud and may trigger the massive star formation in this cloud. This extended methanol emission may also suggest that the 2'N cloud is under shocks. We derive total methanol column density $N(CH_3OH)\;=\;2.9{\pm}0.3{\times}10^{14}\;cm^{-2}$ toward the peak position of the extended emission. The fractional abundance of methanol is about 10.9, relative to the estimated total $H_2$ abundance, which is similar to the methanol abundances in quiet gas phase.

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References

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