Search Publications
Accretion torque reversals in GRO J1008-57 revealed by Insight-HXMT
Wang, W.; Huang, Y.; Wang, C. +92 more
GRO J1008-57, as a Be/X-ray transient pulsar, is considered to have the highest magnetic field in known neutron star X-ray binary systems. Observational data of the X-ray outbursts in GRO J1008-57 from 2017 to 2020 were collected by the Insight-HXMT satellite. In this work, the spin period of the neutron star in GRO J1008-57 was determined to be a…
Redshift evolution of X-ray spectral index of quasars observed by XMM-NEWTON/SDSS
Misra, R.; Hayman, Z. M.; Shehata, SH. M. +2 more
We study the X-ray spectral evolution of quasars with red-shift using a sample of 1280 quasars constructed by cross-referencing the XMM-Newton 3 XMM - DR 7 and the optical SDSS-DR14 catalogues. The sources were selected to have a minimum detected X-ray counts >600 and which were not affected by high background. The sample redshift distribution …
A Suzaku study of the low mass X-ray binary Aquila X-1 in the different states
Abdelbar, Ahmed M.; Beheary, M. M.; Abdelfatah, Ahmed S. +1 more
We present a Suzaku X-ray study for the neutron star low mass X-ray binary Aquila X-1. The observations of the system carried out during three times in 2011 from October 18 to October 24, where the repeated X-ray transient Aquila X-1 was in the rising phase of the outburst. During this period the source was successfully detected in its different s…
In-flight calibration of the Insight-Hard X-ray Modulation Telescope
Zhang, Shu; Li, Xiaobo; Tuo, Youli +19 more
We present the calibration of the Insight-Hard X-ray Modulation Telescope (Insight-HXMT) X-ray satellite, which can be used to perform timing and spectral studies of bright X-ray sources. Insight-HXMT carries three main payloads onboard: the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME) and the low Energy X-ray telescope…
Methodology and performance of the two-year galactic plane scanning survey of Insight-HXMT
Zhang, Shu; Zhang, Shuang-Nan; Liu, Yuan +7 more
The Galactic plane scanning survey is one of the main scientific objectives of the Hard X-ray Modulation Telescope (known as Insight-HXMT). During the two-year operation of Insight-HXMT, more than 1000 scanning observations have been performed and the whole Galactic plane (0∘ < l <360∘, -10∘ < b <10
Multi-wavelength observations of the BL Lac object Fermi J1544-0649: One year after its awakening
Kong, A. K. H.; Tam, P. H. T.; Mao, J. +15 more
We report observations of a transient source Fermi J1544-0649 from radio to γ-rays. Fermi J1544-0649 was discovered by the Fermi-LAT in May 2017. Follow-up Swift-XRT observations revealed three flaring episodes through March 2018, and the peak X-ray flux is about 103 higher than the ROSAT all-sky survey (RASS) flux upper limit. Optical …
Phase-resolved gamma-ray spectroscopy of the Crab pulsar observed by POLAR
Wu, Xin; Ge, Ming-Yu; Zhang, Shuang-Nan +14 more
The POLAR detector is a space based Gamma-Ray Burst (GRB) polarimeter sensitive in the 15-500 keV energy range. Apart from its main scientific goal as a Gamma-Ray Burst polarimeter it is also able to detect photons from pulsars in orbit. By using the six-months in-orbit observation data, significant pulsation from the PSR B0531+21 (Crab pulsar) wa…
Possible correlations between gamma-ray burst and its host galaxy offset
Liu, Yu; Wang, Fei-Fei; Zou, Yuan-Chuan +2 more
We collected the information of 304 gamma-ray bursts (GRBs) from the literature, and analyzed the correlations among the host galaxy offsets (the distance from the site of the GRB to the center of its host galaxy), T90,i (the duration T90 in rest-frame), TR45,i (the duration TR45 in rest-frame), Eγ,…
Interstellar gas and X-rays toward the Young supernova remnant RCW 86; pursuit of the origin of the thermal and non-thermal X-ray
Fukui, Y.; Mitsuishi, I.; Reynoso, E. M. +13 more
We have analyzed the atomic and molecular gas using the 21 cm HI and 2.6/1.3 mm CO emissions toward the young supernova remnant (SNR) RCW 86 in order to identify the interstellar medium with which the shock waves of the SNR interact. We have found an HI intensity depression in the velocity range between -46 and - 28 kms-1 toward the SNR…
Swift discoveries of new populations of extremely long duration high energy transient
Levan, A. J.
Recent observations with Swift have begun to uncover γ-ray transients whose total energies are comparable to those of gamma-ray bursts (GRB), but have a duration an order of magnitude or more longer than the bulk of the GRB population. Some are suggested to form a new population of ultra-long GRBs, with a mean duration around 104 s, whi…