Discovery of H2O, CH3OH, and OH Masers in the Extreme Outer Galaxy
文献类型:期刊论文
作者 | Sun, Yan1,2; Xu, Ye1,2; Chen, Xi3,4; Fang, Min5; Henkel, Christian6,7; Yang, Ji1,2; Menten, Karl M.6; Chen, Xue-Peng1,2; Jiang, Zhi-Bo1,2 |
刊名 | ASTROPHYSICAL JOURNAL |
出版日期 | 2018-12-20 |
卷号 | 869期号:2页码:13 |
ISSN号 | 0004-637X |
关键词 | ISM: molecules masers radio lines: ISM stars: formation |
DOI | 10.3847/1538-4357/aaee86 |
通讯作者 | Sun, Yan(yansun@pmo.ac.cn) |
英文摘要 | We present the results of a single dish interstellar maser survey toward similar to 200 molecular clouds. (MCs) in the extreme outer Galaxy. (EOG) possibly lying in the Outer Scutum- Centaurus. (OSC) arm. The observations resulted in the detections of two new 22.2 GHz water masers, two new 6.7 GHz class II methanol masers, and one new 4765 MHz excited-state OH maser. These new detections include one high Galactic latitude. (b > 2 degrees) methanol maser, one farthest Galactic methanol maser, and one farthest Galactic OH maser from the Sun. The velocities of the masers and the CO emission are in agreement with each other, which strongly indicates an association between the maser and the EOG cloud. The presence of the masers provides reliable evidence for ongoing massive star-forming activity in the OSC arm. The EOG clouds with detected interstellar masers are all associated with young stellar objects. Masers are primarily detected toward the brighter and more massive MCs. Because of the large distances involved, the "faint" masers with luminosity below 10(-6) L-circle dot are not accessible by our current observations. The low number of masers in the EOG regions supports the scenario of decreasing metallicity and decreasing star formation rate/efficiency at large Galactocentric radii. Our new maser detections are valuable targets for future VLBI parallax and proper motion measurements. |
WOS关键词 | STAR-FORMING REGIONS ; II METHANOL MASERS ; ULTRACOMPACT HII-REGIONS ; MOLECULAR CLOUDS ; WATER MASERS ; IRAS SOURCES ; ABUNDANCE GRADIENTS ; ARCETRI CATALOG ; OPTICAL DISK ; MILKY-WAY |
WOS研究方向 | Astronomy & Astrophysics |
语种 | 英语 |
出版者 | IOP PUBLISHING LTD |
WOS记录号 | WOS:000454219200004 |
源URL | [http://libir.pmo.ac.cn/handle/332002/20493] |
专题 | 中国科学院紫金山天文台 |
通讯作者 | Sun, Yan |
作者单位 | 1.Chinese Acad Sci, Purple Mt Observ, Nanjing 210034, Jiangsu, Peoples R China 2.Chinese Acad Sci, Key Lab Radio Astron, Nanjing 210034, Jiangsu, Peoples R China 3.GuangZhou Univ, Ctr Astrophys, Guangzhou 510006, Guangdong, Peoples R China 4.Chinese Acad Sci, Shanghai Astron Observ, Shanghai 200030, Peoples R China 5.Univ Arizona, Dept Astron, 933 North Cherry Ave, Tucson, AZ 85721 USA 6.Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany 7.King Abdulaziz Univ, Dept Astron, POB 80203, Jeddah 21589, Saudi Arabia |
推荐引用方式 GB/T 7714 | Sun, Yan,Xu, Ye,Chen, Xi,et al. Discovery of H2O, CH3OH, and OH Masers in the Extreme Outer Galaxy[J]. ASTROPHYSICAL JOURNAL,2018,869(2):13. |
APA | Sun, Yan.,Xu, Ye.,Chen, Xi.,Fang, Min.,Henkel, Christian.,...&Jiang, Zhi-Bo.(2018).Discovery of H2O, CH3OH, and OH Masers in the Extreme Outer Galaxy.ASTROPHYSICAL JOURNAL,869(2),13. |
MLA | Sun, Yan,et al."Discovery of H2O, CH3OH, and OH Masers in the Extreme Outer Galaxy".ASTROPHYSICAL JOURNAL 869.2(2018):13. |
入库方式: OAI收割
来源:紫金山天文台
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