MASSIVE QUIESCENT CORES IN ORION. V. THE INTERNAL STRUCTURES AND PHYSICAL AND CHEMICAL PROPERTIES OF TWO EXTREMELY DENSE CORES

CORC > 紫金山天文台 > 中国科学院紫金山天文台 > 暗物质和空间天文实验室

	MASSIVE QUIESCENT CORES IN ORION. V. THE INTERNAL STRUCTURES AND PHYSICAL AND CHEMICAL PROPERTIES OF TWO EXTREMELY DENSE CORES
	Ren, Zhiyuan 1,2; Li, Di 1,2,3; Chapman, N.3,4
刊名	ASTROPHYSICAL JOURNAL
	2014-06-20
卷号	788 期号:2
关键词	ISM: abundances ISM: clouds ISM: individual objects (Orion) ISM: kinematics and dynamics ISM: molecules stars: formation stars: pre-main sequence
英文摘要	We present a high-resolution (similar to 1.'' 5) observational study of two massive dust-gas cores, ORI8nw_2 and ORI2_6, in the Orion molecular cloud using the Combined Array for Research in Millimeter-wave Astronomy. In each region the 3.2 mm continuum emission exhibits a dense and compact dust core at the center with 1-3 solar masses. The cores have number densities exceeding 109 cm(-3), which are among the highest volume densities observed in star-forming cores. In both regions the N2H+ shows clumpy structures that are spatially displaced from the densest gas. In OIR8nw_2 in particular, the N2H+ shows a noticeable filament structure with a central cavity shell. The calculation for the dynamical state shows that this core can be potentially supported by the magnetic field against its gravitational instability, but the fragmentation might still occur and produce the observed N2H+ clumps if the gas density exceeds 5 x 10(7) cm(-3) and this value is available within the observed density range. Also, the extremely high density at the core center suggests super-Jeans condition and the possibility for further fragmentation. For the chemical properties, the N2H+-to-HCO+ abundance ratios are shown to be different than those observed in infrared dark clouds. A combined analysis with the other Orion cores and the chemical model suggests that the different abundance ratios can be explained by the low CO abundances in our cores. To further reveal the evolution of such dense cores, higher resolution and sensitivity are required.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	MOLECULAR CLOUD CORES ; HERBIG-HARO FLOWS ; STAR-FORMATION ; MAGNETIC-FIELDS ; A CLOUD ; REGION ; LINE ; EMISSION ; OUTFLOWS ; CLUSTER
收录类别	SCI
语种	英语
WOS记录号	WOS:000337466200075
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/15647]
专题	紫金山天文台_暗物质和空间天文实验室
作者单位	1.Chinese Acad Sci, Natl Astron Observ, Beijing, Peoples R China 2.Chinese Acad Sci, Key Lab Radio Astron, Beijing, Peoples R China 3.Space Sci Inst, Boulder, CO USA 4.CIERA, Dept Phys & Astron, Evanston, IL 60208 USA
推荐引用方式 GB/T 7714	Ren, Zhiyuan,Li, Di,Chapman, N.. MASSIVE QUIESCENT CORES IN ORION. V. THE INTERNAL STRUCTURES AND PHYSICAL AND CHEMICAL PROPERTIES OF TWO EXTREMELY DENSE CORES[J]. ASTROPHYSICAL JOURNAL,2014,788(2).
APA	Ren, Zhiyuan,Li, Di,&Chapman, N..(2014).MASSIVE QUIESCENT CORES IN ORION. V. THE INTERNAL STRUCTURES AND PHYSICAL AND CHEMICAL PROPERTIES OF TWO EXTREMELY DENSE CORES.ASTROPHYSICAL JOURNAL,788(2).
MLA	Ren, Zhiyuan,et al."MASSIVE QUIESCENT CORES IN ORION. V. THE INTERNAL STRUCTURES AND PHYSICAL AND CHEMICAL PROPERTIES OF TWO EXTREMELY DENSE CORES".ASTROPHYSICAL JOURNAL 788.2(2014).