相关论文: Simultaneous NICER and NuSTAR Observations of the …
The detection of coherent X-ray pulsations at ~314 Hz (3.2 ms) classifies MAXI J1957+032 as a fast-rotating, accreting neutron star. We present the temporal and spectral analysis performed using NICER observations collected during the…
We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei, NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray spectra allow detailed modeling of the Compton reflection…
We report the detection of a long X-ray burst triggered on MJD 60171.65 from the ultra-compact binary 4U 1850$-$087 by the Monitor of All-sky X-ray Image and Neutron Star Interior Composition Explorer (NICER). We analyse the NICER data…
We present results from a deep, coordinated $XMM$-$Newton$+$NuSTAR$ observation of the Seyfert 2 galaxy IRAS 00521-7054. The $NuSTAR$ data provide the first detection of this source in high-energy X-rays ($E > 10$ keV), and the broadband…
Accretion disks and coronae around massive black holes have been studied extensively, and they are known to be coupled. Over a period of 30 years, however, the X-ray (coronal) flux of Mrk 817 increased by a factor of 40 while its UV (disk)…
The X-ray burster 4U1850-087, located in the globular cluster NGC6712, is an ultracompact binary likely harbouring a degenerate companion.The source has been observed with INTEGRAL several times, during the monitoring of the Galactic plane,…
We report the broadband spectro-temporal study of the poorly studied accreting neutron star (NS) low mass X-ray binary (LMXB) 4U 1724-30 using data from Soft X-ray Telescope (SXT) and Large Area X-ray Proportional Counters (LAXPC)…
We study the appearance of the neutron star - accretion disk system as seen by a distant observer in the UV/X-ray domain. The observed intensity spectra are computed assuming non-spherical geometry of the whole system, in which outgoing…
We report on the X-ray monitoring programme (covering slightly more than 11 days) carried out jointly by XMM-Newton and NuSTAR on the intermediate Seyfert galaxy Mrk 915. The light curves extracted in different energy ranges show a…
We report the discovery of several optical burst-like events from the low-mass X-ray binary MS1603.6+2600 (UW CrB). The events last for a few tens of seconds, exhibit a very fast rise and slow decay, and involve optical brightening of a…
We study X-ray and soft gamma-ray spectra from the hard state of the accreting black-hole binary MAXI J1820+070. We perform analysis of joint spectra from HXMT, NuSTAR and INTEGRAL. We find an overall agreement between the spectra from all…
It is thought that ultraluminous X-ray sources (ULXs) are mainly powered by super-Eddington accreting neutron stars or black holes as shown by recent discovery of X-ray pulsations and relativistic winds. This work presents a follow up study…
The supernova impostor SN 2010da located in the nearby galaxy NGC 300, later identified as a likely supergiant B[e] high-mass X-ray binary, was simultaneously observed by NuSTAR and XMM-Newton between 2016 December 16 and 20, over a total…
We present the analysis of four NuSTAR observations of the luminous infrared galaxy merger NGC 6240, hosting a close pair of highly obscured active galactic nuclei (AGN). Over a period of about two years, the source exhibits hard X-ray…
A mysterious absorption feature at approximately 3.8 keV has been identified in the NICER spectrum of the low-mass X-ray binary system 4U 1820-30. We interpret this feature as a gravitationally redshifted iron absorption line. This…
We study the mass transfer rates and disk stability conditions of ultracompact X-ray binaries (UCXBs) using empirical time-averaged X-ray luminosities from Paper I (Cartwright et al. 2013) and compiled information from the literature. The…
The recent discovery of periodic pulsations from several members of the ultraluminous X-ray source (ULX) family in nearby galaxies as well as in our own galaxy unveiled the nature of the accreting compact object. Neutron stars rather than…
We present the detection of 51 thermonuclear X-ray bursts observed from 4U 1636-536 by the Neutron Star Interior Composition Explorer (NICER) over the course of a three year monitoring campaign. We performed time resolved spectroscopy for…
We perform a comprehensive study of thermonuclear bursts from the neutron star low-mass X-ray binary 4U 1702-429 detected with NICER and XMM-Newton. The thermonuclear burst detected with NICER shows clear evidence of a photospheric radius…
Based on new Chandra X-ray telescope data, we present empirical evidence of plasma Compton cooling during a flare in the non pulsating massive X-ray binary 4U1700-37. This behaviour might be explained by quasispherical accretion onto a…