NEWLY IDENTIFIED EXTENDED GREEN OBJECTS (EGOs) FROM THE SPITZER GLIMPSE II SURVEY. II. MOLECULAR CLOUD ENVIRONMENTS

	NEWLY IDENTIFIED EXTENDED GREEN OBJECTS (EGOs) FROM THE SPITZER GLIMPSE II SURVEY. II. MOLECULAR CLOUD ENVIRONMENTS
	Chen, Xi 1,2; Gan, Cong-Gui 1,2; Ellingsen, Simon P.3; He, Jin-Hua 4; Shen, Zhi-Qiang 1,2; Titmarsh, Anita 3
刊名	ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
	2013-06-01
卷号	206 期号:2
关键词	infrared: ISM ISM: jets and outflows radio lines: ISM stars: formation
ISSN号	0067-0049
通讯作者	Chen,X
英文摘要	We have undertaken a survey of molecular lines in the 3 mm band toward 57 young stellar objects using the Australia Telescope National Facility Mopra 22 m radio telescope. The target sources were young stellar objects with active outflows (extended green objects (EGOs)) newly identified from the GLIMPSE II survey. We observe a high detection rate (50%) of broad line wing emission in the HNC and CS thermal lines, which combined with the high detection rate of class I methanol masers toward these sources (reported in Paper I) further demonstrates that the GLIMPSE II EGOs are associated with outflows. The physical and kinematic characteristics derived from the 3 mm molecular lines for these newly identified EGOs are consistent with these sources being massive young stellar objects with ongoing outflow activity and rapid accretion. These findings support our previous investigations of the mid-infrared properties of these sources and their association with other star formation tracers (e. g., infrared dark clouds, methanol masers and millimeter dust sources) presented in Paper I. The high detection rate (64%) of the hot core tracer CH3CN reveals that the majority of these new EGOs have evolved to the hot molecular core stage. Comparison of the observed molecular column densities with predictions from hot core chemistry models reveals that the newly identified EGOs from the GLIMPSE II survey are members of the youngest hot core population, with an evolutionary time scale of the order of 103 yr.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	MASSIVE STAR-FORMATION ; INFRARED DARK CLOUDS ; MULTIBEAM MASER CATALOG ; YOUNG STELLAR OBJECTS ; GHZ METHANOL MASERS ; HOT-CORE REGIONS ; FORMING REGIONS ; DENSE CORES ; CHEMICAL EVOLUTION ; CH3CN OBSERVATIONS
收录类别	SCI
语种	英语
WOS记录号	WOS:000325654800013
公开日期	2014-05-22
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/10103]
专题	紫金山天文台_期刊（老文献）
作者单位	1.Chinese Acad Sci, Shanghai Astron Observ, Key Lab Res Galaxies & Cosmol, Shanghai 200030, Peoples R China 2.Chinese Acad Sci, Key Lab Radio Astron, Nanjing, Jiangsu, Peoples R China 3.Univ Tasmania, Sch Math & Phys, Hobart, Tas, Australia 4.Chinese Acad Sci, Natl Astron Observ, Yunnan Astron Observ, Key Lab Struct & Evolut Celestial Objects, Kunming 650011, Yunnan Province, Peoples R China
推荐引用方式 GB/T 7714	Chen, Xi,Gan, Cong-Gui,Ellingsen, Simon P.,et al. NEWLY IDENTIFIED EXTENDED GREEN OBJECTS (EGOs) FROM THE SPITZER GLIMPSE II SURVEY. II. MOLECULAR CLOUD ENVIRONMENTS[J]. ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES,2013,206(2).
APA	Chen, Xi,Gan, Cong-Gui,Ellingsen, Simon P.,He, Jin-Hua,Shen, Zhi-Qiang,&Titmarsh, Anita.(2013).NEWLY IDENTIFIED EXTENDED GREEN OBJECTS (EGOs) FROM THE SPITZER GLIMPSE II SURVEY. II. MOLECULAR CLOUD ENVIRONMENTS.ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES,206(2).
MLA	Chen, Xi,et al."NEWLY IDENTIFIED EXTENDED GREEN OBJECTS (EGOs) FROM THE SPITZER GLIMPSE II SURVEY. II. MOLECULAR CLOUD ENVIRONMENTS".ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 206.2(2013).