OH Evolution in Molecular Clouds
OH Evolution in Molecular Clouds
复制标题
分子云中的 OH 演化
DOI：
10.3847/1538-4365/abca94
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发表时间：
2020-10
期刊：
影响因子：
--
通讯作者：
Heiles Carl
中科院分区：
文献类型：
--
作者：
Tang Ningyu;Li Di;Yue Nannan;Zuo Pei;Liu Tie;Luo Gan;Chen Longfei;Qin Sheng-Li;Wu Yuefang;Heiles Carl
我们用阿雷西博望远镜对141个不同环境下的分子云进行了OH 18 cm测量，其中包括33个光学暗云，98个普朗克银河冷团（PGCC）和10个斯皮策暗云。OH主线和卫星线的强度比偏离局部热平衡是共同的。在小于3 mG时，OH 1667 MHz谱线强度与可见光消光系数呈线性关系，采用蒙特卡罗模拟得到的激发温度（1σ不确定度），将谱线强度转换为OH柱密度。OH丰度X（OH）相对于H_2的比值与~（13）CO强度呈线性关系。此外，OH和13 CO的非热速度色散密切相关。这些结果暗示了OH和13 CO之间紧密的化学演化和空间占位。柱密度与OH和H i窄自吸收（HINSA）的非热速度色散之间没有明显的相关性，表明OH和HINSA之间的化学演化和空间体积占有不同。利用HINSA分析的年龄信息，发现OH丰度X（OH）随云龄线性增加，这与以前的模拟结果一致。14个OH组分没有相应的CO排放被检测到，这意味着OH示踪的“CO暗”分子气体的有效性。
We have conducted a OH 18 cm survey toward 141 molecular clouds in various environments, including 33 optical dark clouds, 98 Planck Galactic cold clumps (PGCCs), and 10 Spitzer dark clouds with the Arecibo telescope. The deviations from local thermal equilibrium are common for intensity ratios of both OH main lines and satellite lines. Line intensity of OH 1667 MHz is found to correlate linearly with visual extinction when is less than 3 mag. It was converted into OH column density by adopting the excitation temperature derived from Monte Carlo simulations with 1σ uncertainty. The relationship between OH abundance X(OH) relative to H2 and is found to follow an empirical formula, Linear correlation is found between OH and 13CO intensity. Besides, nonthermal velocity dispersions of OH and 13CO are closely correlated. These results imply tight chemical evolution and spatial occupation between OH and 13CO. No obvious correlation is found between column density and nonthermal velocity dispersion of OH and H i narrow self-absorption (HINSA), indicating different chemical evolution and spatial volume occupation between OH and HINSA. Using the age information of HINSA analysis, OH abundance X(OH) is found to increase linearly with cloud age, which is consistent with previous simulations. Fourteen OH components without corresponding CO emission were detected, implying the effectiveness of OH in tracing the “CO-dark” molecular gas.
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影响因子：
3.5
作者：
C. Heiles;P. Perillat;M. Nolan;D. Lorimer;R. Bhat;T. Ghosh;E. Howell;M. Lewis;K. O’Neil;C. Salter;S. Stanimirović
通讯作者：
C. Heiles;P. Perillat;M. Nolan;D. Lorimer;R. Bhat;T. Ghosh;E. Howell;M. Lewis;K. O’Neil;C. Salter;S. Stanimirović
影响因子：
6.5
作者：
M. Rugel;H. Beuther;S. Bihr;Yuting Wang;Juergen Ott;A. Brunthaler;Andrew Walsh;S. Glover;P. Goldsmith;L. Anderson;Nicola Schneider;K. Menten;S. Ragan;J. Urquhart;R. Klessen;J. D. Soler;N. Roy;J. Kainulainen;T. Henning;F. Bigiel;Rory J. E. Smith;F. Wyrowski;S. Longmore
通讯作者：
M. Rugel;H. Beuther;S. Bihr;Yuting Wang;Juergen Ott;A. Brunthaler;Andrew Walsh;S. Glover;P. Goldsmith;L. Anderson;Nicola Schneider;K. Menten;S. Ragan;J. Urquhart;R. Klessen;J. D. Soler;N. Roy;J. Kainulainen;T. Henning;F. Bigiel;Rory J. E. Smith;F. Wyrowski;S. Longmore
DOI：
10.3847/1538-4357/ab3a4b
发表时间：
2019-08
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Michael P. Busch;R. Allen;P. Engelke;D. E. Hogg;D. Neufeld;M. Wolfire
通讯作者：
Michael P. Busch;R. Allen;P. Engelke;D. E. Hogg;D. Neufeld;M. Wolfire
影响因子：
8.7
作者：
E. Dishoeck;J. Black
通讯作者：
E. Dishoeck;J. Black
DOI：
10.1111/j.1365-2966.2010.17105.x
发表时间：
2010-10-01
影响因子：
4.8
作者：
Barriault, L.;Joncas, G.;Martin, P. G.
通讯作者：
Martin, P. G.