Search Publications
A Study on White Dwarf Masses in Cataclysmic Variables Based on XMM-Newton and Suzaku Observations
Li, Xiang-Dong; Xu, Xiao-Jie; Yu, Zhuo-Li
The distribution of the mass of white dwarfs (WDs) is one of the fundamental questions in the field of cataclysmic variables (CVs). In this work, we make a systematical investigation on the WD masses in two subclass of CVs: intermediate polars (IPs) and non-magnetic CVs in the solar vicinity based on the flux ratios of Fe XXVI-Lyα to Fe XXV-Heα em…
Broad-band spectroscopy of the transient X-ray binary pulsar KS 1947+300 during 2013 giant outburst: Detection of pulsating soft X-ray excess component
Naik, Sachindra; Jaisawal, Gaurava K.; Epili, Prahlad
We present the results obtained from detailed timing and spectral studies of the Be/X-ray binary pulsar KS 1947+300 during its 2013 giant outburst. We used data from Suzaku observations of the pulsar at two epochs, i.e. on 2013 October 22 (close to the peak of the outburst) and 2013 November 22. X-ray pulsations at ∼18.81 s were clearly detected i…
The orbital phase resolved spectroscopy of X-ray binary 4U 1822-371 with Suzaku
Ji, Li; Nowak, Michael A.; Schulz, Norbert S. +3 more
4U 1822-371 is a typical edge-on eclipsing low mass X-ray binary and the prototype of accretion disk coronal sources. We report on the results of a spectral analysis over the energy range 0.5-45 keV observed by Suzaku in 2006. We extract spectra from five orbital phases. The spectra can be equally well described by various previously proposed mode…
Suzaku observation of Be/X-ray binary pulsar EXO 2030+375
Naik, Sachindra; Jaisawal, Gaurava K.
We study the timing and spectral properties of Be/X-ray binary pulsar EXO 2030+375 using a Suzaku observation taken on 2012 May 23, during a less intense Type I outburst. Pulsations were clearly detected in the X-ray light curves at a barycentric period of 41.2852 s, which suggest that the pulsar is spinning-up. The pulse profiles were found to be…
Understanding the X-ray spectrum of anomalous X-ray pulsars and soft gamma-ray repeaters
Liu, Yuan; Guo, Yan-Jun; Tong, Hao +3 more
Hard X-rays above 10 keV are detected from several anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs), and different models have been proposed to explain the physical origin within the frame of either a magnetar model or a fallback disk system. Using data from Suzaku and INTEGRAL, we study the soft and hard X-ray spectra of four AX…
Temporal variations and spectral properties of the Be/X-ray pulsar GRO J1008—57 studied by INTEGRAL
Wang, Wei
The spin period variations and hard X-ray spectral properties of the Be/X-ray pulsar GRO J1008—57 are studied with INTEGRAL observations during two outbursts in 2004 June and 2009 March. The pulsation periods of ~ 93.66 s in 2004 and ~ 93.73 s in 2009 are determined. Pulse profiles of GRO J1008—57 during outbursts are strongly energy dependent wit…
X-ray spectroscopy of clusters of galaxies
Ota, Naomi
Clusters of galaxies are the most massive objects in the Universe and precise knowledge of their mass structure is important to understand the history of structure formation and constrain still unknown types of dark contents of the Universe. X-ray spectroscopy of galaxy clusters provides rich information about the physical state of hot intracluste…
Multifrequency emission analysis of TeV blazars H 2356-309 and 1ES 1218+304
Zhang, Li; Tang, Yun-Yong; Dai, Zu-Cheng
The multiband nonthermal emissions in radio, X-ray, and very high-energy (VHE) γ-ray bands from two distant blazars, H 2356-309 and 1ES 1218+304, have been detected, and, especially from recent observations with the Suzaku, MAGIC and VERITAS telescopes, clearly reveal nonthermal power-law spectra. We study the broadband nonthermal spectra of the t…