Multiwavelength observations of the BL lacertae object PKS 2155-304 with XMM-Newton

	Multiwavelength observations of the BL lacertae object PKS 2155-304 with XMM-Newton
	Zhang, YH1 ; Bai JM(白金明)2 ; Zhang, SN 1; Treves, A 3; Maraschi, L 4; Celotti, A 5
刊名	ASTROPHYSICAL JOURNAL
	2006-11-10
卷号	651 期号:2 页码:782-790
关键词	BL Lacertae objects : individual (PKS 2155-304) galaxies : active methods : data analysis ultraviolet : galaxies X-rays : galaxies
ISSN号	0004-637X
通讯作者	Zhang, YH (reprint author), Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China.
产权排序	第二完成单位
英文摘要	The optical/UV and X-ray instruments on board XMM-Newton provide an excellent opportunity to perform simultaneous observations of violently variable objects over a broad wavelength range. The UV- and X-ray-bright BL Lac object PKS 2155-304 has been observed repeatedly with XMM-Newton about twice per year. In this paper, we present a detailed analysis of the simultaneous multiwavelength variability of the source from optical to X-rays, based on the currently available XMM-Newton observations. These observations probed the intraday multiwavelength variability at optical/UV and X-ray wavelengths of the source. The UV variability amplitude is substantially smaller than the X-ray one, and the hardness ratios of the UV to X-rays correlates with the X-ray fluxes: the brighter the source, the flatter the UV/X-ray spectra. On 2000 May 30-31, the UV and X-ray light curves were weakly correlated, while the UV variations followed the X-ray ones with no detectable lags on 2000 November 19-21. On 2001 November 30, the source exhibited a major X-ray flare that was not detected in the optical. The intraday UV and X-ray variability presented here is not similar to the interday UV and X-ray variability obtained from the previous coordinated extensive multiwavelength campaigns on the source, indicating that different "modes'' of variability might be operating in PKS 2155-304 on different timescales or from epoch to epoch.
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 ; X-RAY VARIABILITY ; LOG-PARABOLIC SPECTRA ; ENERGY GAMMA-RAYS ; PKS 2155-304 ; PARTICLE-ACCELERATION ; EPIC-PN ; MARKARIAN 501 ; IUE CAMPAIGN ; EMISSION
收录类别	SCI
原文出处	http://iopscience.iop.org/0004-637X/651/2/782/
语种	英语
WOS记录号	WOS:000241825000016
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/4945]
专题	云南天文台_高能天体物理研究组
作者单位	1.Department of Physics and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084, China 2.National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, P.O. Box 110, Kunming, Yunnan 650011, China 3.Dipartimento di Scienze, Universit? degli Studi dell'Insubria, via Valleggio 11, I-22100 Como, Italy 4.Osservatorio Astronomico di Brera, via Brera 28, I-20121 Milan, Italy 5.International School for Advanced Studies, SISSA/ISAS, via Beirut 2-4, I-34014 Trieste, Italy
推荐引用方式 GB/T 7714	Zhang, YH,Bai JM,Zhang, SN,et al. Multiwavelength observations of the BL lacertae object PKS 2155-304 with XMM-Newton[J]. ASTROPHYSICAL JOURNAL,2006,651(2):782-790.
APA	Zhang, YH,Bai JM,Zhang, SN,Treves, A,Maraschi, L,&Celotti, A.(2006).Multiwavelength observations of the BL lacertae object PKS 2155-304 with XMM-Newton.ASTROPHYSICAL JOURNAL,651(2),782-790.
MLA	Zhang, YH,et al."Multiwavelength observations of the BL lacertae object PKS 2155-304 with XMM-Newton".ASTROPHYSICAL JOURNAL 651.2(2006):782-790.