Two-component model for the interstellar scattering in direction to the Vela pulsar

	Two-component model for the interstellar scattering in direction to the Vela pulsar
	Zhou, AZ ; Esamdin, A ; Wu, XJ
刊名	ASTRONOMY & ASTROPHYSICS
	2005-08-01
卷号	438 期号:3 页码:909-914
关键词	stars : pulsars : individual : PSR B0833-45 radio continuum : stars ISM : structure scattering
通讯作者	Astronomy & Astrophysics
英文摘要	This paper discusses a rigorous treatment of the refractive scintillation of pulsar PSR B0833-45 caused by a two-component interstellar scattering medium. It is assumed that the interstellar scattering medium is composed of a thin screen ISM and an extended interstellar medium. We consider that the scattering of the thin screen concentrates in a thin layer presented by a delta function distribution and that the scattering density of the extended irregular medium satisfies the Gaussian distribution. We investigate and develop equations for the flux density structure function corresponding to this two-component ISM geometry in the scattering density distribution and compare our result with that of the Vela pulsar observations. We conclude that the refractive scintillation caused by this two-component ISM scattering gives a more satisfactory explanation for the observed flux density variation of the Vela pulsar than does the single extended medium model. The level of refractive scintillation is strongly sensitive to the distribution of scattering material along the line of sight. The logarithmic slope of the structure function is sensitive to thin screen location and is relatively insensitive to the scattering strength of the thin screen medium. Therefore, the proposed model can be applied to interpret the structure function of flux density observed in pulsar PSR B0833-45. The result suggests that the medium consists of a discontinuous distribution of plasma turbulence embedded in the Vela supernova remnant. Thus our work provides some insight into the distribution of the scattering along the line of sight to the Vela pulsar.
学科主题	射电天文学
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	LONG-TERM SCINTILLATION ; FLUX-DENSITY VARIATIONS ; INTENSITY VARIATIONS ; REFRACTIVE SCINTILLATION ; GALACTIC DISTRIBUTION ; SUPERNOVA REMNANT ; PLASMA-DENSITY ; FREE-ELECTRONS ; SPECTRUM ; DISTANCE
收录类别	SCI
语种	英语
WOS记录号	WOS:000230611600016
公开日期	2010-04-29
内容类型	期刊论文
源URL	[http://119.78.226.72//handle/331011/8029]
专题	上海天文台_VLBI研究室
作者单位	1.Chinese Acad Sci, Shanghai Astron Observ, Shanghai 200030, Peoples R China 2.Chinese Acad Sci, Urumqi Stn, Natl Astron Observ, Urumqi 830011, Peoples R China 3.Peking Univ, Dept Astron, Beijing 100871, Peoples R China
推荐引用方式 GB/T 7714	Zhou, AZ,Esamdin, A,Wu, XJ. Two-component model for the interstellar scattering in direction to the Vela pulsar[J]. ASTRONOMY & ASTROPHYSICS,2005,438(3):909-914.
APA	Zhou, AZ,Esamdin, A,&Wu, XJ.(2005).Two-component model for the interstellar scattering in direction to the Vela pulsar.ASTRONOMY & ASTROPHYSICS,438(3),909-914.
MLA	Zhou, AZ,et al."Two-component model for the interstellar scattering in direction to the Vela pulsar".ASTRONOMY & ASTROPHYSICS 438.3(2005):909-914.