Study on the Physical and Chemical Properties of a Thermally Inhibited Dense Structure in W51 IRS2

Journal of Chuxiong Normal University ›› 2024, Vol. 39 ›› Issue (3): 16-21.

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Study on the Physical and Chemical Properties of a Thermally Inhibited Dense Structure in W51 IRS2

TANG Mengyao^1,2, RUAN Meng², CHEN Xingpeng², YANG Hudie², LI Liandeng²

1. Institute of Astrophysics, Chuxiong Normal University, Chuxiong, Yunnan Province 675000;
2. School of Physics and Electronic Science, Chuxiong Normal University, Chuxiong, Yunnan Province 675000

Received:2023-11-13 Online:2024-05-20 Published:2024-06-05

Abstract

Abstract: This work analyzes and processes high-resolution (0.028'') observation data of the W51 IRS2 region, a massive star-forming region, obtained by the ALMA. For the first time, an unfragmented, ultra-dense clump-like structure called CE1 was observed, with a mass greater than 13 solar masses and a density higher than 107. Vibrational (v8=1) and rotational (v=0) transitions of CH₃CN molecule were detected in a total of 16 spectral transitions, and the parameters of CH₃CN were calculated. From Jeans analysis, it was found that the temperature inside CE 1 should be higher than 400 K, and no obvious star formation activity was observed inside. All the research results suggest that CE 1 is highly possible an “embryo” in a very early evolutionary stage of massive star formation.

Key words: massive star formation, interstellar medium, molecular spectrum

CLC Number:

P152

TANG Mengyao, RUAN Meng, CHEN Xingpeng, YANG Hudie, LI Liandeng. Study on the Physical and Chemical Properties of a Thermally Inhibited Dense Structure in W51 IRS2[J]. Journal of Chuxiong Normal University, 2024, 39(3): 16-21.

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Study on the Physical and Chemical Properties of a Thermally Inhibited Dense Structure in W51 IRS2

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