A precise measurement of the orbital period parameters of Cygnus X-3
Yash Bhargava, A. R. Rao, K. P. Singh, Manojendu Choudhury, S. Bhattacharyya, S. Chandra, G. C. Dewangan, K. Mukerjee, G. C. Stewart, D. Bhattacharya, N. P. S. … 展开作者
Yash Bhargava, A. R. Rao, K. P. Singh, Manojendu Choudhury, S. Bhattacharyya, S. Chandra, G. C. Dewangan, K. Mukerjee, G. C. Stewart, D. Bhattacharya, N. P. S. Mithun, S. V. Vadawale
备注：
8 pages, 7 figures, Accepted for publication in ApJ
We present X-ray light curves of Cygnus X-3 as measured by the recently launched AstroSat satellite. The light curve folded over the binary period of 4.8 hours shows a remarkable stability over the past 45 years and we find that we can use this information to measure the zero point to better than 100 s. We revisit the historical binary phase measurements and examine the stability of the binary period over 45 years. We present a new binary ephemeris with the period and period derivative determined to an accuracy much better than previously reported. We do not find any evidence for a second derivative in the period variation. The precise binary period measurements, however, indicate a hint of short term episodic variations in periods. Interestingly, these short term period variations coincide with the period of enhanced jet activity exhibited by the source. We discuss the implications of these observations on the nature of the binary system.
XRISM High-Resolution X-ray Spectroscopy of Cygnus X-1 -- Orbital and Short-Term Variability of Iron Absorption
Tokyo University of Science（东京科学大学）；Rikkyo University（立教大学）；Lawrence Livermore National Laboratory（劳伦斯利弗莫尔国家实验室）；SRON Netherlands Institute for Space Research（荷兰空间研究所）；California Institute of Technology（加州理工学院）；University of Michigan（密歇根大学）；Massachusetts Institute of Technology（麻省理工学院）；Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA)（日本宇宙航空研究开发机构宇宙科学研究所）
From GeV to PeV: Orbital Modulation and Wind-Regulated Ultrahigh-energy Emission in Cygnus~X-3
School of Astronomy and Space Science, Nanjing University（南京大学天文与空间科学学院）；Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education（教育部现代天文学和天体物理学重点实验室（南京大学））；Tianfu Cosmic Ray Research Center（天府宇宙线研究中心）；State Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences（中国科学院高能物理研究所粒子天体物理国家重点实验室）
Chandra X-Ray Spectroscopy of the Focused Wind in the Cygnus X-1 System. II. The Nondip Spectrum in the Low/Hard State - Modulations with Orbital Phase
Energy-Resolved Limits on Orbital X-ray Polarization Modulation in Cygnus X-1
Washington University in St. Louis（华盛顿大学）；European Space Agency (ESA), European Space Research and Technology Centre (ESTEC)（欧洲空间局（ESA），欧洲空间研究与技术中心（ESTEC））
