Dense gas and the nature of the outflows

CORC > 紫金山天文台 > 中国科学院紫金山天文台 > 分子云与恒星形成研究团组

	Dense gas and the nature of the outflows
	Sepulveda, I.1; Anglada, G.2; Estalella, R.1; Lopez, R.1; Girart, J. M.3; Yang, J.4
刊名	ASTRONOMY & ASTROPHYSICS
	2011-03-01
卷号	527 页码:A41
关键词	ISM: jets and outflows ISM: molecules stars: formation
ISSN号	0004-6361
英文摘要	We present the results of the observations of the (J, K) = (1, 1) and the (J, K) = (2, 2) inversion transitions of the NH3 molecule toward a large sample of 40 regions with molecular or optical outflows, using the 37 m radio telescope of the Haystack Observatory. We detected NH3 emission in 27 of the observed regions, which we mapped in 25 of them. Additionally, we searched for the 6(16)-5(23) H2O maser line toward six regions, detecting H2O maser emission in two of them, HH265 and AFGL 5173. We estimate the physical parameters of the regions mapped in NH3 and analyze for each particular region the distribution of high density gas and its relationship with the presence of young stellar objects. In particular, we identify the deflecting high-density clump of the HH270/110 jet. We were able to separate the NH3 emission from the L1641-S3 region into two overlapping clouds, one with signs of strong perturbation, probably associated with the driving source of the CO outflow, and a second, unperturbed clump, which is probably not associated with star formation. We systematically found that the position of the best candidate for the exciting source of the molecular outflow in each region is very close to an NH3 emission peak. From the global analysis of our data we find that in general the highest values of the line width are obtained for the regions with the highest values of mass and kinetic temperature. We also found a correlation between the nonthermal line width and the bolometric luminosity of the sources, and between the mass of the core and the bolometric luminosity. We confirm with a larger sample of regions the conclusion of Anglada et al. (1997) that the NH3 line emission is more intense toward molecular outflow sources than toward sources with optical outflow, suggesting a possible evolutionary scheme in which young stellar objects associated with molecular outflows progressively lose their neighboring high-density gas, weakening both the NH3 emission and the molecular outflow in the process, and making optical jets more easily detectable as the total amount of gas decreases.
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]	YOUNG STELLAR OBJECTS ; HERBIG-HARO OBJECTS ; STAR-FORMING REGIONS ; H-II REGIONS ; PROTOSTELLAR COLLAPSE CANDIDATES ; NOBEYAMA MILLIMETER ARRAY ; RADIO-CONTINUUM EMISSION ; NGC-7538 MOLECULAR CLOUD ; MAIN-SEQUENCE OBJECTS ; FAR-INFRARED SOURCES
收录类别	SCI
语种	英语
WOS记录号	WOS:000287484100056
公开日期	2012-08-07
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/4405]
专题	紫金山天文台_分子云与恒星形成研究团组
作者单位	1.Univ Barcelona, Inst Ciencies Cosmos, Dept Astron & Meteorol, E-08028 Barcelona, Catalunya, Spain 2.CSIC, Inst Astrofis Andalucia, E-18008 Granada, Spain 3.CSIC IEEC, Fac Ciencies, Inst Ciencies Espai, Bellaterra 08193, Catalunya, Spain 4.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China
推荐引用方式 GB/T 7714	Sepulveda, I.,Anglada, G.,Estalella, R.,et al. Dense gas and the nature of the outflows[J]. ASTRONOMY & ASTROPHYSICS,2011,527:A41.
APA	Sepulveda, I.,Anglada, G.,Estalella, R.,Lopez, R.,Girart, J. M.,&Yang, J..(2011).Dense gas and the nature of the outflows.ASTRONOMY & ASTROPHYSICS,527,A41.
MLA	Sepulveda, I.,et al."Dense gas and the nature of the outflows".ASTRONOMY & ASTROPHYSICS 527(2011):A41.