Related papers: Activity from Magnetar Candidate 4U 0142+61: Burst…
The NuSTAR hard X-ray telescope observed the transient Be/X-ray binary GS 0834-430 during its 2012 outburst - the first active state of this system observed in the past 19 years. We performed timing and spectral analysis, and measured the…
RXTE observations of the X-ray transient pulsar 2S 1417-62 between 1999 November and 2000 August with a total exposure of $\sim 394$ ksec were analyzed. Observations include a main outburst followed by a series of mini outbursts. Changes in…
XTE J1810-197 is the first transient Anomalous X-ray Pulsar ever discovered. Its highly variable X-ray flux allowed us to study the timing and spectral emission properties of a magnetar candidate over a flux range of about two orders of…
Significant research in compact stars is currently focused on two kinds of enigmatic sources: anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs). Although AXPs and SGRs are popularly thought to be magnetars, other models…
Accreting X-ray pulsars (XRPs) undergo luminous X-ray outbursts during which the spectral and timing behavior of the neutron star can be studied in detail. We analyze a $NuSTAR$ observation of the XRP XTE J1858+034 during its outburst in…
We report on data obtained with the Chandra, XMM-Newton, Suzaku and Swift X-ray observatories, following the 2006 outburst of the Anomalous X-ray Pulsar CXO J164710.2-455216. We find no evidence for the very large glitch and rapid…
We represent noise strength analysis of Anomalous X-Ray Pulsars (AXPs) 4U 0142+61, 1RXS J170849.9-400910, 1E 1841-045, 1E 2259+586 and Soft Gamma Repeaters (SGRs) SGR J1833-0832, SWIFT J1822.3-1606 and SWIFT J1834.9-0846 together with the…
Two flares with a duration of several hours are reported for the low-mass X-ray binary 4U 1636-53. The characteristics of these flares (i.e., decay time scales, spectral softening, fluences) are very similar to the very long type-I X-ray…
We present the first Suzaku observation of the new Soft Gamma Repeater SGR 0501+4516, performed on 2008 August 26, four days after the onset of bursting activity of this new member of the magnetar family. The soft X-ray persistent emission…
Thanks to INTEGRAL's long exposures of the Galactic Plane, the two brightest Soft Gamma-Ray Repeaters, SGR 1806-20 and SGR 1900+14, have been monitored and studied in detail for the first time at hard-X/soft gamma rays. This has produced a…
The population of clearly identified anomalous X-ray pulsars has recently grown to seven, however, one candidate anomalous X-ray pulsar (AXP) still eludes re-confirmation. Here, we present a set of seven Chandra ACIS-S observations of the…
We report the discovery of a highly coherent oscillation in a type-I X-ray burst observed from 4U 1916-053 by the Rossi X-ray Timing Explorer (RXTE). The oscillation was most strongly detected approx. 1 s after the burst onset at a…
Using data from the Large Area X-ray Proportional Counter (LAXPC) on the \textit{AstroSat} satellite, we observed the Type-1 thermonuclear X-ray bursts from the Low Mass X-ray Binary Neutron Star 4U 1323-62. The observations of 4U 1323-62…
Energetic bursts from strongly magnetized neutron stars, known as magnetars, are typically detected in clusters. Once an active episode begins, anywhere from a few to thousands of hard X-ray bursts can occur over durations ranging from days…
Two sensitive Chandra X-ray observations of the heavily-reddened galactic starburst cluster Westerlund 1 in May and June 2005 detected a previously unknown X-ray pulsar (CXO J164710.20-455217). Its slow 10.6 s pulsations, moderate X-ray…
The Soft Gamma Repeater SGR 1900+14 entered a remarkable phase of activity during the summer of 1998. This activity peaked on August 27, 1998 when a giant periodic gamma-ray flare resembling the famous March 5, 1979 event from SGR 0526-66…
Observational evidence has been accumulating that thermonuclear X-ray bursts ignited on the surface of neutron stars influence the surrounding accretion flow. Here, we exploit the excellent sensitivity of NuSTAR up to 79 keV to analyze the…
We report on a series of outbursts of the high mass X-ray binary XTE J1946+274 in 2010/2011 as observed with INTEGRAL, RXTE, and Swift. We discuss possible mechanisms resulting in the extraordinary outburst behavior of this source. The…
We report results obtained from the study of 12 thermonuclear X-ray bursts in 6 AstroSat observations of a neutron star X-ray binary and well-known X-ray burster, 4U 1636$-$536. Burst oscillations at $\sim$581 Hz are observed with…
After in quiescence for 49 years, 4U~1730--22 became active and had two outbursts in 2021 \& 2022; ten thermonuclear X-ray bursts were detected with Insight-HXMT. Among them, the faintest burst showed a double-peaked profile, placing the…