A λ 3 mm Line Survey toward the Circumstellar Envelope of the Carbon-rich AGB Star IRC+10216 (CW Leo)

Autor: Juan Tuo, Xiaohu Li, Jixian Sun, Tom J. Millar, Yong Zhang, Jianjie Qiu, Donghui Quan, Jarken Esimbek, Jianjun Zhou, Yu Gao, Qiang Chang, Lin Xiao, Yanan Feng, Zhenzhen Miao, Rong Ma, Ryszard Szczerba, Xuan Fang
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: The Astrophysical Journal Supplement Series, Vol 271, Iss 2, p 45 (2024)
Druh dokumentu: article
ISSN: 1538-4365
0067-0049
DOI: 10.3847/1538-4365/ad2460
Popis: We present an unbiased λ 3 mm spectral line survey (between 84.5 and 115.8 GHz), conducted by the Purple Mountain Observatory 13.7 m radio telescope, together with updated modeling results, toward the carbon-rich asymptotic giant branch star IRC+10216 (CW Leo). A total of 75 spectral lines (96 transitions) are detected, and identified to arise from 19 molecules: C _2 H, l -C _3 H, C _4 H, CN, C _3 N, HC _3 N, HC _5 N, HCN, HNC, CH _3 CN, MgNC, CO, c -C _3 H _2 , SiC _2 , SiO, SiS, CS, C _2 S, C _3 S, and their isotopologues. Among them, one molecular emission line (H ^13 CCCN J = 13–12) is discovered in IRC+10216 for the first time. The excitation temperature, column density, and fractional abundance of the detected species are deduced by assuming they are in local thermodynamic equilibrium. In addition, the isotopic ratios of [ ^12 C]/[ ^13 C], [ ^32 S]/[ ^34 S], [ ^28 Si]/[ ^29 Si], and [ ^12 C ^34 S]/[ ^13 C ^32 S] are obtained and found to be consistent with previous studies. Finally, we summarize all of the 106 species detected in IRC+10216 to date with their observed and modeled column densities for the convenience of future studies.
Databáze: Directory of Open Access Journals