Orbital period analysis of eclipsing dwarf novae: U Geminorum

doi:10.1007/s10509-009-9982-0

YNAO OpenIR > 双星与变星研究组

	Orbital period analysis of eclipsing dwarf novae: U Geminorum
	Dai ZB(戴智斌); Qian SB(钱声帮); Dai, ZB (reprint author), Chinese Acad Sci, Natl Astron Observ, Yunnan Observ, POB 110, Kunming 650011, Peoples R China.
发表期刊	ASTROPHYSICS AND SPACE SCIENCE
	2009-05
卷号	321 期号:2 页码:91-100
DOI	10.1007/s10509-009-9982-0
产权排序	第1完成单位
收录类别	SCI
关键词	Stars: Cataclysmic Variables Stars: Binaries: Eclipsing Stars: Individual u Geminorum
摘要	A new orbital period analysis for U Geminorum is made by means of the standard O-C technique based on 187 times of light minima including the three newest CCD data from our observation. Although there are large scatter near 70,000 cycles in its O-C diagram, there is strong evidence (>99.9% confidence level) to show the secular increase of orbital period with a rate (P) over dot = 7.8(1) x 10(-12) s(-1). Using the physical parameters recently derived by Echevarr a et al. (Astron. J. 134: 262, 2007), the range of mass transfer rate for U Geminorum is estimated as from-3.5(5) x 10(-9) M(circle dot) yr(-1) to-1.30(6) x 10(-8) M(circle dot) yr(-1). Moreover, the data before 60,000 cycles shows the obvious quasi-period variations. The least square estimation of a similar to 17.4 yr quasi-periodic variation superimposed on secular orbital period increase is derived. Considering the possibility that solar-type magnetic activity cycles in the secondary star of U Geminorum may produce the quasi-period variations of the orbital period, Applegate's mechanism is discussed and the results indicate such mechanism has difficulty explaining the quasi-period variation for U Geminorum. Hence, we attempted to apply the light-travel time effect to interpret the quasi-period variation and found the perturbation of similar to 17.4 yr quasi-period may result from a brown dwarf. If the orbital inclination is assumed as i similar to 15 degrees, corresponding to the upper limit of mass of a brown dwarf, then its orbital radii is similar to 7.7 AU.
项目资助者	Yunnan Natural Science Foundation [2005A0059M] ; Chinese Natural Science [10573032, 10573013, 10433030]
语种	英语
学科领域	Astronomy & Astrophysics
文章类型	Article
ISSN	0004-640X
URL	查看原文
归档日期	2009-06-02
WOS记录号	WOS:000265440200002
WOS研究方向	Astronomy & Astrophysics
WOS类目	Astronomy & Astrophysics
关键词[WOS]	CATACLYSMIC VARIABLES ; ADDITIONAL TIMES ; T AURIGAE ; EX HYDRAE ; BINARIES ; COMPONENTS ; OUTBURST ; MINIMA ; GEM
引用统计	被引频次：11[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.ynao.ac.cn/handle/114a53/5824
专题	双星与变星研究组
通讯作者	Dai, ZB (reprint author), Chinese Acad Sci, Natl Astron Observ, Yunnan Observ, POB 110, Kunming 650011, Peoples R China.
推荐引用方式 GB/T 7714	Dai ZB,Qian SB,Dai, ZB . Orbital period analysis of eclipsing dwarf novae: U Geminorum[J]. ASTROPHYSICS AND SPACE SCIENCE,2009,321(2):91-100.
APA	戴智斌,钱声帮,&Dai, ZB .(2009).Orbital period analysis of eclipsing dwarf novae: U Geminorum.ASTROPHYSICS AND SPACE SCIENCE,321(2),91-100.
MLA	戴智斌,et al."Orbital period analysis of eclipsing dwarf novae: U Geminorum".ASTROPHYSICS AND SPACE SCIENCE 321.2(2009):91-100.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
Orbital period analy（558KB）	期刊论文	作者接受稿	开放获取	CC BY-NC-SA	浏览请求全文