Coupling between the 45 Hz horizontal-branch oscillation and the normal-branch oscillation in Scorpius X-1

	Coupling between the 45 Hz horizontal-branch oscillation and the normal-branch oscillation in Scorpius X-1
	Yu, Wenfei
刊名	ASTROPHYSICAL JOURNAL
	2007-04-20
卷号	659 期号:2 页码:L145-L148
关键词	accretion stars : individual (Scorpius X-1) stars : neutron X-rays : stars accretion disks
英文摘要	The observations of the bright persistent neutron star low-mass X-ray binary (LMXB) Sco X-1 performed with the Rossi X-Ray Timing Explorer (RXTE) show a similar to 6 Hz normal-branch oscillation (NBO), a similar to 45 Hz horizontal-branch oscillation (HBO), and twin kilohertz quasi-periodic oscillations (kHz QPOs) on its normal branch simultaneously. We have found that the fractional amplitude of the HBO corresponding to the NBO phase of high flux is 1.1%, while that of the NBO phase of low flux is undetectable, with a 3 sigma upper limit of 0.4%, implying that the HBO strength varies with the NBO phase in a manner opposite that of the lower kHz QPO previously found, and suggests that the condition for the generation of the HBO is met when the NBO flux is high. The 6 Hz NBO in Sco X-1 connects the 45 Hz HBO and the twin kHz QPO together, showing a unique picture indicating a coupling between the QPOs, which has never been observed in other neutron star LMXBs. We discuss the implications for current models of the 45 Hz HBO, the 6 Hz NBO, and the twin kHz QPOs.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	QUASI-PERIODIC OSCILLATIONS ; X-RAY BINARIES ; ACCRETING BLACK-HOLES ; NEUTRON-STAR ; FREQUENCY ; DEPENDENCE ; FEATURES ; MODEL
收录类别	SCI
语种	英语
WOS记录号	WOS:000245775000016
内容类型	期刊论文
源URL	[http://119.78.226.72/handle/331011/19421]
专题	上海天文台_星系宇宙学重点实验室
作者单位	Shanghai Astron Observ, Shanghai 200030, Peoples R China
推荐引用方式 GB/T 7714	Yu, Wenfei. Coupling between the 45 Hz horizontal-branch oscillation and the normal-branch oscillation in Scorpius X-1[J]. ASTROPHYSICAL JOURNAL,2007,659(2):L145-L148.
APA	Yu, Wenfei.(2007).Coupling between the 45 Hz horizontal-branch oscillation and the normal-branch oscillation in Scorpius X-1.ASTROPHYSICAL JOURNAL,659(2),L145-L148.
MLA	Yu, Wenfei."Coupling between the 45 Hz horizontal-branch oscillation and the normal-branch oscillation in Scorpius X-1".ASTROPHYSICAL JOURNAL 659.2(2007):L145-L148.