REVISING THE KINEMATICS OF 12 GHz CH3OH MASERS TOWARD W3(OH)

	REVISING THE KINEMATICS OF 12 GHz CH3OH MASERS TOWARD W3(OH)
	Moscadelli, L.1; Xu, Y.2 ; Chen, X.3
刊名	ASTROPHYSICAL JOURNAL
	2010-06-20
卷号	716 期号:2 页码:1356-1370
关键词	H II regions ISM: individual objects (W3(OH)) ISM: kinematics and dynamics masers techniques: interferometric
英文摘要	We derive accurate proper motions of the CH3OH 12 GHz masers toward the W3(OH) ultra-compact (UC) H II region, employing seven epochs of VLBA observations spanning a time interval of about 10 yr. The achieved velocity accuracy is of the order of 0.1 km s(-1), adequate to precisely measure the relative velocities of most of the 12 GHz masers in W3(OH), with amplitude varying in the range 0.3-3 km s(-1). Toward W3(OH), the most intense 12 GHz masers concentrate in a small area toward the north (the northern clump) of the UC H II region. We have compared the proper motions of the CH3OH 12 GHz masers with those (derived from literature data) of the OH 6035 MHz masers, emitting from the same region of the methanol masers. In the northern clump, the two maser emissions emerge from nearby (but likely distinct) cloudlets of masing gas with, in general, a rather smooth variation of line-of-sight and sky-projected velocities, which suggests some connection of the environments and kinematics traced by both maser types. The conical outflow model, previously proposed to account for the 12 GHz maser kinematics in the northern clump, does not reproduce the new, accurate measurements of 12 GHz maser proper motions and has to be rejected. We focus on the subset of 12 GHz masers of the northern clump belonging to the "linear structure at P.A. = 130 degrees-140 degrees," whose regular variation of LSR velocities with position presents evidence for some ordered motion. We show that the three-dimensional velocities of this " linear distribution" of 12 GHz masers can be well fitted considering a flat, rotating disk, seen almost edge-on.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	HIGH-SPECTRAL-RESOLUTION ; YOUNG STELLAR OBJECTS ; METHANOL MASERS ; OH MASERS ; PROPER MOTIONS ; DISC
收录类别	SCI
语种	英语
WOS记录号	WOS:000278459000037
内容类型	期刊论文
源URL	[http://119.78.226.72/handle/331011/26345]
专题	上海天文台_星系宇宙学重点实验室
作者单位	1.Osserv Astrofis Arcetri, INAF, I-50125 Florence, Italy 2.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China 3.Chinese Acad Sci, Shanghai Astron Observ, Shanghai 200030, Peoples R China
推荐引用方式 GB/T 7714	Moscadelli, L.,Xu, Y.,Chen, X.. REVISING THE KINEMATICS OF 12 GHz CH3OH MASERS TOWARD W3(OH)[J]. ASTROPHYSICAL JOURNAL,2010,716(2):1356-1370.
APA	Moscadelli, L.,Xu, Y.,&Chen, X..(2010).REVISING THE KINEMATICS OF 12 GHz CH3OH MASERS TOWARD W3(OH).ASTROPHYSICAL JOURNAL,716(2),1356-1370.
MLA	Moscadelli, L.,et al."REVISING THE KINEMATICS OF 12 GHz CH3OH MASERS TOWARD W3(OH)".ASTROPHYSICAL JOURNAL 716.2(2010):1356-1370.