NAOC Open IR
Short-period near-contact binary systems at the beginning of the overcontact phase
Qian, SB
2002-11-11
Source PublicationMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
ISSN0035-8711
Volume336Issue:4Pages:1247-1255
AbstractA detailed analysis of orbital period changes of seven near-contact binary stars (NCBs) (BL And, V473 Cas, XZ CMi, BV Eri, RU Eri, UU Lyn and GR Tau) with period less than 1 d has been performed and their respective O-C diagrams are formed and discussed. It is found that all systems analysed show secular period decreasing. For V473 Cas, the analysis of the period change was performed based on data collected by Moschner, Frank & Bastian. For XZ CMi, its period shows some complex changes, a possible cyclic oscillation is discovered to superpose on the secular decrease that can be explained either by the presence of a third body or by magnetic activity cycles of the components. Since the third-body assumption is consistent with the photometric solution of Rafert, XZ CMi may be a truly triple system. For BV Eri, the period decrease is only supported by weak evidence. All the seven systems are short-period NCBs with AF-type primary components where both components are filling or nearly filling the critical Roche lobe. As the period decreases, the separation between both components will be reducing and thus these systems will evolve into A-type overcontact binaries. The period decrease may be caused by mass transfer or/and by angular momentum loss via magnetic braking. Combined with the published data on the other systems of the same type, a possible statistical connection between orbital period P and its rate of decrease dP/dt is obtained: dP/dt = -5.3 x 10(-7) x P + 1.3 x 10(-7) d yr(-1). This correlation indicates that the smaller the orbital period P is, the smaller its rate of change dP/dt will be. The correlation found in this paper indicates that there may be a smooth transition from A- and F-type NCBs with period decreases to the A- and F-type overcontact binaries that have period increases, and in that sense one may postulate that the NCBs may be the progenitors of the A-type W UMa systems and will be oscillating around a marginal-contact state as predicted by thermal relaxation oscillation (TRO) theory.
Keywordbinaries : close stars : evolution stars : mass-loss
WOS KeywordURSAE MAJORIS SYSTEMS ; XZ CANIS-MINORIS ; UBV PHOTOMETRY ; BV ERIDANI ; GR TAURI ; EVOLUTION ; LIGHT ; MASS
Language英语
WOS Research AreaAstronomy & Astrophysics
WOS SubjectAstronomy & Astrophysics
WOS IDWOS:000178981200024
PublisherBLACKWELL PUBLISHING LTD
Citation statistics
Document Type期刊论文
Identifierhttp://ir.bao.ac.cn/handle/114a11/37434
Collection中国科学院国家天文台
Corresponding AuthorQian, SB
Affiliation1.Chinese Acad Sci, Natl Astron Observ, Yunnan Observ, Kunming 650011, Peoples R China
2.Chinese Acad Sci, ULOAC, United Lab Opt Astron, Beijing 100012, Peoples R China
Recommended Citation
GB/T 7714
Qian, SB. Short-period near-contact binary systems at the beginning of the overcontact phase[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2002,336(4):1247-1255.
APA Qian, SB.(2002).Short-period near-contact binary systems at the beginning of the overcontact phase.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,336(4),1247-1255.
MLA Qian, SB."Short-period near-contact binary systems at the beginning of the overcontact phase".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 336.4(2002):1247-1255.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Qian, SB]'s Articles
Baidu academic
Similar articles in Baidu academic
[Qian, SB]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Qian, SB]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.