Related papers: EXO 2030+375 Restarts in Reverse
The bursting pulsar, GRO J1744-28, went again in outburst after $\sim$18 years of quiescence in mid-January 2014. We studied the broad-band, persistent, X-ray spectrum using X-ray data from a XMM-Newton observation, performed almost at the…
We report the results of an analysis of data obtained with the INTEGRAL, Swift and RXTE observatories during the 2010 April and September outbursts of the X-ray pulsar RX J0440.9+4431. The temporal and spectral properties of the pulsar in a…
After 34 years, the black-hole candidate EXO 1846-031 went into outburst again in 2019. We investigate its spectral properties in the hard intermediate and the soft states with NuSTAR and Insight-HXMT. A reflection component has been…
LS I +61 303 is an exceptionally rare example of a high mass X-ray binary (HMXB) that also exhibits MeV-TeV emission, making it one of only a handful of "gamma-ray binaries". Here we present H-alpha spectra that show strong variability…
We present a comprehensive analysis of 2RXP J130159.6-635806, a persistent low-luminosity Be/X-ray pulsar, focusing on its transition to a spin equilibrium state and the discovery of a bimodal luminosity distribution revealing possibly a…
Cen X-3 is an archetypical X-ray pulsar with strong flux variations and alternating torque reversals, both of which are similar to those of recently discovered pulsating ultra-luminous X-ray sources. We study a low state of Cen X-3 occurred…
The black hole candidate XTE J2012+381 underwent an outburst at the end of 2022. We analyzed 105 NICER observations and 2 NuSTAR observations of the source during the outburst. The NuSTAR observations of the $M \sim10M_\odot$ black hole…
We report strong evidence for a ~304-day periodicity in the spin history of the accretion-powered pulsar GX1+4 that is most probably associated with the orbital period of the system. We have used data from the Burst and Transient Source…
We present spectral and timing analysis of NuSTAR observations of RX J0520.5$-$6932 in the 3-79 keV band collected during its outburst in January 2014. The target was observed on two epochs and we report the detection of a cyclotron…
The Bursting Pulsar, GRO J1744-28, has been observed with the Rossi X-ray Timing Explorer (RXTE) regularly since the launch of the satellite in December 1995. This accretion driven pulsar has undergone two outbursts which have been…
Accreting X-ray pulsars provide us with laboratories for the study of extreme gravitational and magnetic fields, hence accurate descriptions of their observational properties contribute to our understanding of this group of objects. We aim…
X-ray emission from the supermassive binary system Eta Carinae declines sharply around periastron. This X-ray minimum has two distinct phases - the lowest flux phase in the first ~3 weeks and a brighter phase thereafter. In 2009, the…
Frequency glitches have been observed so far only in radio pulsars and anomalous X-ray pulsars. Here we present evidence of a glitch in a neutron star accreting from a Be companion. The transient KS 1947+300 reappeared in 2000 October as a…
We present the optical spectroscopic observations of X Per from 1999 to 2013 with the 2.16m telescope at Xinglong Station and the 2.4m telescope at Lijiang station, National Astronomical Observatories of China. Combining with the public…
We present MAXI and NuSTAR observations of the Be X-ray binary, MAXI J0655-013, in outburst. NuSTAR observed the source once early in the outburst, when spectral analysis yields a bolometric (0.1--100 keV), unabsorbed source luminosity of…
We report the detection of pulsations at 552 Hz in the rising phase of two type-I (thermonuclear) X-ray bursts observed from the accreting neutron star EXO 0748-676 in 2007 January and December, by the Rossi X-ray Timing Explorer. The…
We present the first broadband spectral and timing study of the Be/X-ray pulsar XTE J0111.2$-$7317 (SXP31.0) during the first major outburst since its discovery in 1998. This giant type II outburst, observed between April and September…
We tested the ejector-propeller model of the Be/X-ray binary LSI+61303 (V 615 Cas, GT 0236+620) by using the parameters predicted by the model in the calculations of the X-ray and radio variability. The results are: (1) in terms of the…
We carried out I, R, V and B photometric observations of the neutron star X-ray binary RXTE J2123-058 shortly after the end of the X-ray outburst in mid-1998. We adopt the low mass binary model to interpret our observations. After folding…
(Abridged) We present results of several X-ray observations of the X-ray binary 4U 1954+31 performed with the satellites BeppoSAX, EXOSAT, ROSAT, RXTE, and Swift. We also studied the RXTE ASM data over a period of more than 10 years. Light…