Limiting the accretion disc light in two mass transferring hot subdwarf binaries
Limiting the accretion disc light in two mass transferring hot subdwarf binaries
复制标题
限制两个质量传递热亚矮星双星中的吸积盘光
DOI：
10.1093/mnras/stac3492
复制
发表时间：
2022
影响因子：
4.8
通讯作者：
Piirola, Vilppu
中科院分区：
文献类型：
--
作者：
Deshmukh, Kunal;Kupfer, Thomas;Hakala, Pasi;Bauer, Evan B.;Berdyugin, Andrei;Bildsten, Lars;Marsh, Thomas R.;Mereghetti, Sandro;Piirola, Vilppu
我们报告了对两个罗氏叶填充热亚矮星双星的后续观测结果，预计白矮星伴星具有吸积盘。周期为39分钟的ZTF J213056.71+442046.5 （ZTF J2130）和周期为56分钟的ZTF J205515.98+465106.5 （ZTF J2055）都是被发现的亚矮星双星，它们的光曲线只能通过在它们的模型中包含吸积盘来解释。我们进行了详细的高分辨率光谱分析，使用Keck/ESI来搜索这两个物体可能的吸积特征。我们还使用北欧光学望远镜（NOT）对ZTF J2130进行了偏振分析。我们在两个天体中都没有发现吸积盘的任何特征，并对由于吸积盘引起的通量贡献和偏振度变化设定了上限。由于ZTF J2130的周期很短，只有39分钟，并且有超过6年的光度数据，我们进行了广泛的o - Ctiming分析，试图寻找引力波辐射引起的轨道衰减。没有这样的衰变被最终检测到，并且几年的数据与精确和一致的时间测量相结合被认为是必要的，以限制观测。
We report the results from follow-up observations of two Roche-lobe filling hot subdwarf binaries with white dwarf companions predicted to have accretion discs. ZTF J213056.71+442046.5 (ZTF J2130) with a 39-min period and ZTF J205515.98+465106.5 (ZTF J2055) with a 56-min period were both discovered as subdwarf binaries with light curves that could only be explained well by including an accretion disc in their models. We performed a detailed high-resolution spectral analysis, using Keck/ESI to search for possible accretion features for both objects. We also employed polarimetric analysis using the Nordic Optical Telescope (NOT) for ZTF J2130. We did not find any signatures of an accretion disc in either object, and placed upper limits on the flux contribution and variation in degree of polarization due to the disc. Owing to the short 39-min period and availability of photometric data over 6 yr for ZTF J2130, we conducted an extensiveO−Ctiming analysis in an attempt to look for orbital decay due to gravitational wave radiation. No such decay was detected conclusively, and a few more years of data paired with precise and consistent timing measurements were deemed necessary to constrainobservationally.