An investigation of binary stars in the Pleiades with high contrast and spatial resolution

Please use this identifier to cite or link to this item: https://ir.lib.ncu.edu.tw/handle/987654321/100672

Title:	An investigation of binary stars in the Pleiades with high contrast and spatial resolution
Authors:	陳文屏;Richichi, A.;Chen, W. P.;Cusano, F.;Fors, O.;Moerchen, M.;Komonjinda, S.
Contributors:	理學院天文研究所
Keywords:	binaries: general;occultations;stars: fundamental parameters;techniques: high angular resolution
Date:	2012-01-01
Issue Date:	2026-04-21 14:10:18 (UTC+8)
Publisher:	EDP Sciences
Abstract:	摘要： Context. It is widely recognized that binarity is a very common feature during star formation; however, different regions and clusters display significantly different binary fractions. This appears to be related to the initial density of the star forming region. The Pleiades cluster has been shown to have a binary fraction similar to that of field stars in the solar neighborhood. Aims. We have taken advantage of a passage of the Moon over the Pleiades cluster, to investigate at high angular resolution two small but similar and consistent samples of cluster members and field stars. Methods. We have employed the technique of lunar occultations (LO). Although LO in the Pleiades have been reported several times in the past, we have for the first time employed the superior performance of the VLT, achieving about 1 milliarcsecond (mas) resolution and detecting sources as faint as K ≈ 12 mag. Results. We have recorded 17 LO light curves of stars recognized as cluster members, and 17 of field stars. The average magnitude was K ≈ 8.5 mag and the average limiting resolution ≈0.″002, for both samples. We detect 5 binaries among the cluster members, and 2 among the sample of field stars. Three systems are new detections, while two were previously only suspected to be binaries. The projected separations are in the range 0.″017 to 0.″642 and the brightness ratios in the range 1 to 90. One more star is suspected to have a companion. Conclusions. Although the fraction of binary detections appears higher among the members than among the non-members, the two samples are too small to draw firm conclusions. Our observations show that, in spite of extensive investigations carried out previously in the Pleiades cluster, the binarity census is not yet complete. We have detected significant orbital motion in four binary systems, which stand up as candidates for dynamical mass estimations. 出版者： EDP Sciences 出版日期： 2012-05-01 出處： Astronomy and astrophysics (Berlin), 2012-05, Vol.541, p.A96 資源來源： EDP Sciences 識別號： ISSN: 0004-6361 識別號： ISSN: 1432-0746 識別號： EISSN: 1432-0746 識別號： DOI: 10.1051/0004-6361/201219041
Appears in Collections:	[Graduate Institute of Astronomy] journal & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	12	View/Open

社群 sharing

Loading...