ORIGIN OF THE X-RAYS AND POSSIBLE GeV-TeV EMISSION FROM THE WESTERN HOT SPOT OF PICTOR A

	ORIGIN OF THE X-RAYS AND POSSIBLE GeV-TeV EMISSION FROM THE WESTERN HOT SPOT OF PICTOR A
	Zhang J(张晋)1,2,3 ; Bai JM(白金明)1 ; Chen L(陈亮)1,3 ; Yang, Xian 1
刊名	ASTROPHYSICAL JOURNAL
	2009-08-10
卷号	701 期号:1 页码:423-427
关键词	galaxies: individual (Pictor A) gamma rays: theory radiation mechanisms: non-thermal X-rays: galaxies
ISSN号	0004-637X
通讯作者	Zhang, J (reprint author), Chinese Acad Sci, Natl Astron Observ, Yunnan Observ, POB 110, Kunming 650011, Yunnan, Peoples R China.
产权排序	第一完成单位
英文摘要	Pictor A is a nearby Fanaroff-Riley class II (FR II) radio galaxy with a bright hot spot, the western hot spot. Observation of high polarization in the optical emission of the hot spot indicates that the optical emission could be synchrotron radiation of relativistic electrons in the hot spot. These electrons may be able to produce high-energy gamma-ray photons through inverse Compton scattering. We use single-zone and multizone synchrotron + synchrotron self-Compton models to fit the observed spectral energy distribution (SED) from the radio to the X-ray band of the hot spot. Our results show that in the case of a much weaker magnetic field strength than the equipartition magnetic field, both the single-zone and multizone models can fit the SED, but the multizone model significantly improves the fit. The two models predict the hot spot as a GeV-TeV source, which might be marginally detectable with Fermi/LAT and H. E. S. S. The inverse Compton scattering of cosmic microwave background is also considered, but its contribution to GeV-TeV emission is negligible. Note that under the equipartition condition, the SED can also be fitted with the multizone model, but the predicted flux at >10(22) Hz is too weak to be detectable. The detection of TeV gamma-rays from this FR II radio galaxy, if confirmed, would establish a new subclass of extragalactic sources in this energy regime since most of the active galactic nuclei detected to date at TeV energies are high-energy-peaked BL Lac objects.
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]	ACTIVE GALACTIC NUCLEI ; RADIO GALAXY PICTOR ; PEAKED BL-LACERTAE ; MAGNETIC-FIELD STRENGTHS ; SELF-COMPTON MODEL ; GAMMA-RAYS ; SYNCHROTRON SPECTRA ; JET ; DISCOVERY ; BLAZARS
收录类别	SCI
原文出处	http://iopscience.iop.org/0004-637X/701/1/423/
语种	英语
WOS记录号	WOS:000268341800035
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/4979]
专题	云南天文台_高能天体物理研究组
作者单位	1.National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, P.O. Box 110, Kunming, Yunnan 650011, China 2.College of Physics and Electronic Engineering, Guangxi Teachers Education University, Nanning, Guangxi 530001, China 3.The Graduate School of Chinese Academy of Sciences, China
推荐引用方式 GB/T 7714	Zhang J,Bai JM,Chen L,et al. ORIGIN OF THE X-RAYS AND POSSIBLE GeV-TeV EMISSION FROM THE WESTERN HOT SPOT OF PICTOR A[J]. ASTROPHYSICAL JOURNAL,2009,701(1):423-427.
APA	Zhang J,Bai JM,Chen L,&Yang, Xian.(2009).ORIGIN OF THE X-RAYS AND POSSIBLE GeV-TeV EMISSION FROM THE WESTERN HOT SPOT OF PICTOR A.ASTROPHYSICAL JOURNAL,701(1),423-427.
MLA	Zhang J,et al."ORIGIN OF THE X-RAYS AND POSSIBLE GeV-TeV EMISSION FROM THE WESTERN HOT SPOT OF PICTOR A".ASTROPHYSICAL JOURNAL 701.1(2009):423-427.