Dynamical Modeling of CXOGBS J175553.2-281633: A 10 Hour Long Orbital Period Cataclysmic Variable
Sebastian Gomez, Manuel A. P. Torres, Peter G. Jonker, Zuzanna Kostrzewa-Rutkowska, Theo F. J. van Grunsven, Andrzej Udalski, Robert I. Hynes, Craig O. Heinke, … 展开作者
Sebastian Gomez, Manuel A. P. Torres, Peter G. Jonker, Zuzanna Kostrzewa-Rutkowska, Theo F. J. van Grunsven, Andrzej Udalski, Robert I. Hynes, Craig O. Heinke, Thomas J. Maccarone, Ricardo Salinas, Jay Strader
We present modeling of the long-term optical light curve and radial velocity curve of the binary stellar system CXOGBS J175553.2-281633, first detected in X-rays in the \textit{Chandra} Galactic Bulge Survey. We analyzed 7 years of optical I-band photometry from OGLE and found long-term variations from year to year. These long-term variations can most likely be explained with by either variations in the luminosity of the accretion disk or a spotted secondary star. The phased light curve has a sinusoidal shape, which we interpret as being due to ellipsoidal modulations. We improve the orbital period to be $P = 10.34488 \pm 0.00006$ h with a time of inferior conjunction of the secondary star $T_0 = {\rm HJD\ } 2455260.8204 \pm 0.0008$. Moreover, we collected 37 spectra over 6 non-consecutive nights. The spectra show evidence for an evolved K7 secondary donor star, from which we obtain a semi-amplitude for the radial velocity curve of $K_2 = 161 \pm 6 $ km s$^{-1}$. Using the light curve synthesis code {\tt XRbinary}, we derive the most likely orbital inclination for the binary of $i = 63.0\pm0.7$ deg, a primary mass of $M_1 = 0.83 \pm 0.06$ M$_\odot$, consistent with a white dwarf accretor, and a secondary donor mass of $M_2 = 0.65 \pm 0.07$ M$_\odot$, consistent with the spectral classification. Therefore, we identify the source as a long orbital period cataclysmic variable star.
The optical photometric and spectroscopic periodicities of the cataclysmic variable SRGt 062340.2-265751
Leibniz-Institut für Astrophysik Potsdam (AIP)（波茨坦阿基米德天体物理研究所）；University of Potsdam（波茨坦大学）；South African Astronomical Observatory（南非天文台）；University of Cape Town（开普敦大学）；University of the Free State（自由州大学）；Durham University（杜伦大学）；Radboud University（拉德堡德大学）；Dartmouth College（达特茅斯学院）
Confirmation of SRGt 062340.2-265751 as a nova-like cataclysmic variable with a possible magnetic nature
Leibniz-Institut für Astrophysik Potsdam（波茨坦阿斯特罗物理莱布尼茨研究所）；Institut für Astronomie und Astrophysik Tübingen, Universität Tübingen（蒂宾根大学天文与天体物理研究所）；Potsdam University（波茨坦大学）；South African Astronomical Observatory（南非天文台）；University of Cape Town（开普敦大学）；University of the Free State（自由州大学）；Max-Planck-Institut für Extraterrestrische Physik（马克斯·普朗克地外物理研究所）；Durham University（杜伦大学）
Where do the Progenitors of Millisecond Pulsars come from?
对大量毫秒脉冲星（MSP）的观测表明，它们的轨道周期有很大的差异（从大约几小时到几个月）。在标准观点中，低质量X射线双星（LMXB）被认为是回收过程中某些MSP的祖先。我们提出了一个系统的研究，结合了不同类型的紧凑对象的二进制文件，如灾难性的变量（CV），LMXB和MSP。我们将它们一起绘制在所谓的Corbet图中。需要更大和不同的样本来更好地将结果约束为环境和地层的函数。一个比例图，显示了不同轨道周期的MSP分布以及它们的祖先依赖于双星中白矮星的吸积诱导坍缩（AIC）的方面。因此，大质量CV（M > 1.1 M \odot）对双星演化以及中子星及其磁场的形成和演化的物理过程起着至关重要的作用，并可能转变为具有不同轨道周期尺度的双星MSP;这种效应可以用AIC过程来解释。这种情况也表明，银河系盘中的一些孤立的MSP可以通过相同的通道形成，形成一些CV对Ia型超新星的单简并祖先的贡献。此外，我们已经通过使用更新的数据改进了统计分布和演变。这意味着在二进制系统中的紧凑对象的重要研究可以受益于Corbet图。
Periodic Radio and X-ray Emission from an Accreting White Dwarf Binary
The University of Sydney（悉尼大学）；Australia Telescope National Facility, CSIRO（澳大利亚望远镜国家设施，CSIRO）；ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav)（引力波发现卓越研究中心（OzGrav））；University of Wisconsin-Milwaukee（威斯康星大学密尔沃基分校）；Curtin University（科廷大学）；University of North Carolina, Chapel Hill（北卡罗来纳大学教堂山分校）
White dwarf + M dwarf Detached Binaries in Long Period Radio Transients: Observed Binary Parameters, Evolution, and Population Constraints
California Institute of Technology（加州理工学院）；Sydney Institute for Astronomy, School of Physics, The University of Sydney（悉尼大学物理学院天文研究所）；ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav)（ARC引力波发现卓越中心（OzGrav））；University of Oxford（牛津大学）；Curtin University（科廷大学）
