EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES

	EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES
	Lei, Ya-Juan1 ; Zhang, Hao-Tong1 ; Zhang, Cheng-Min1 ; Qu, Jin-Lu 2; Yuan, Hai-Long1 ; Dong, Yi-Qiao1 ; Zhao, Yong-Heng1 ; Wang, De-Hua 3; Yin, Hong-Xing 4; Zhang, Yan-Xia1
刊名	ASTRONOMICAL JOURNAL
	2013-09-01
卷号	146 期号:3
关键词	accretion, accretion disks binaries: close stars: individual (4U 1735-44) X-rays: binaries
英文摘要	We analyze the cross-correlation function between the soft and hard X-rays of atoll source 4U 1735-44 with RXTE data, and find anti-correlated soft and hard time lags of about a hecto-second. In the island state, the observations do not show any obvious correlations, and most observations of the banana branch show a positive correlation. However, anti-correlations are detected in the upper banana branch. These results are different from those of Z-sources (Cyg X-2, GX 5-1), where anti-correlations are detected in the horizontal branch and upper normal branch. In this case, the lag timescales of both this atoll and Z-sources are found to be similar, at a magnitude of several tens to hundreds of seconds. As a comparison, it is noted that anti-correlated lags lasting thousands of seconds have been reported from several black hole candidates in their intermediate states. In addition, for an observation containing four segments that show positive or anti-correlation, we analyze the spectral evolution with the hybrid model. In the observation, the anti-correlation is detected at the highest flux. The fitting results show that the Comptonized component is not the lowest at the highest flux, which suggests that the anti-correlation corresponds to the transition between the soft and hard states. Finally, we compare the corresponding results of atoll source 4U 1735-44 with those observed in Z-sources and black hole candidates, and the possible origins of the anti-correlated time lags are discussed.
收录类别	SCI
语种	英语
WOS记录号	WOS:000323302700017
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/5881]
专题	国家天文台_光学天文研究部
作者单位	1.Chinese Acad Sci, Natl Astron Observ, Key Lab Opt Astron, Beijing 100012, Peoples R China 2.Chinese Acad Sci, Inst High Energy Phys, Ctr Particle Astrophys, Beijing 100049, Peoples R China 3.Beijing Normal Univ, Dept Astron, Beijing 100875, Peoples R China 4.Shandong Univ, Sch Space Sci & Phys, Weihai 264209, Peoples R China
推荐引用方式 GB/T 7714	Lei, Ya-Juan,Zhang, Hao-Tong,Zhang, Cheng-Min,et al. EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES[J]. ASTRONOMICAL JOURNAL,2013,146(3).
APA	Lei, Ya-Juan.,Zhang, Hao-Tong.,Zhang, Cheng-Min.,Qu, Jin-Lu.,Yuan, Hai-Long.,...&Song, Li-Ming.(2013).EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES.ASTRONOMICAL JOURNAL,146(3).
MLA	Lei, Ya-Juan,et al."EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES".ASTRONOMICAL JOURNAL 146.3(2013).