文章基本信息

标题：Optical Studies of 15 Hard X-Ray Selected Cataclysmic Binaries
本地全文：下载
作者：Jules P. Halpern ; John R. Thorstensen ; Patricia Cho 等
期刊名称：The Astronomical journal
印刷版ISSN：0004-6256
电子版ISSN：1538-3881
出版年度：2018
卷号：155
期号：6
页码：1-24
DOI：10.3847/1538-3881/aabfd0
语种：English
出版社：American Institute of Physics
摘要：We conducted time-resolved optical spectroscopy and/or time-series photometry of 15 cataclysmic binaries that were discovered in hard X-ray surveys by the Swift Burst Alert Telescope and the International Gamma-Ray Astrophysics Laboratory, with the goal of measuring their orbital periods and searching for spin periods. Four of the objects in this study are new optical identifications: Swift J0535.2+2830, Swift J2006.4+3645, IGR J21095 +4322, and Swift J2116.5+5336. Coherent pulsations are detected from three objects for the first time, Swift J0535.2+2830 (1523 s), 2PBC J1911.4+1412 (747 s), and 1SWXRT J230642.7+550817 (464 s), indicating that they are intermediate polars (IPs). We find two new eclipsing systems in time-series photometry: 2PBC J0658.0 −1746, a polar with a period of 2.38hr, and Swift J2116.5+5336, a disk system that has an eclipse period of 6.56hr. Exact or approximate spectroscopic orbital periods are found for six additional targets. Of note is the long 4.637-day orbit for Swift J0623.9−0939, which is revealed by the radial velocities of the photospheric absorption lines of the secondary star. We also discover a 12.76hr orbital period for RX J2015.6+3711, which confirms that the previously detected 2.00hr X-ray period from this star is the spin period of an IP, as inferred by Coti Zelati et al. These results support the conclusion that hard X-ray selection favors magnetic CVs, with IPs outnumbering polars.
关键词：novae;cataclysmic variables;X-rays: binaries