Related papers: Evidence for accretion rate change during type I X…
We report High Energy Transient Explorer 2 (HETE-2) Wide Field X-ray Monitor/French Gamma Telescope observations of XRF030723 along with observations of the XRF afterglow made using the 6.5m Magellan Clay telescope and the Chandra X-ray…
Outbursts of young stellar objects occur when the mass accretion rate suddenly increases. However, such outbursts are difficult to detect for deeply embedded protostars due to their thick envelope and the rarity of outbursts. The near-IR…
We investigate the effect of the hot CNO cycle breakout reaction 15O(alpha,gamma)19Ne on the occurrence of type I X-ray bursts on accreting neutron stars. For f_rp <~ 0.1, where f_rp is a dimensionless factor by which we multiply the…
Type-I X-ray bursts observed from neutron stars originate from intermittent unstable thermonuclear burning of accreted matter on these stars. Such bursts, particularly those reaching the Eddington luminosity and having a temporary…
Evidence abounds that young stellar objects undergo luminous bursts of intense accretion that are short compared to the time it takes to form a star. It remains unclear how much these events contribute to the main-sequence masses of the…
AA Tau was observed for about 5h per XMM orbit (2 days) over 8 successive orbits, which covers two optical eclipse periods (8.2 days). The XMM optical/UV monitor simultaneously provided UV photometry with a ~15 min sampling rate. Some…
We analyze the frequency evolution of millisecond oscillations observed during type I X-ray bursts with the Rossi X-ray Timing Explorer in order to establish the stability of the mechanism underlying the oscillations. Our sample contains 68…
We use archival data from the Rossi X-Ray Timing Explorer to examine 125 type I X-ray bursts from the 9 weakly magnetic accreting neutron stars where millisecond oscillations have been detected during some bursts. We find that oscillations…
We report the analysis of the first superburst from a transiently accreting neutron star system with the All-Sky Monitor (ASM) on the Rossi X-ray Timing Explorer. The superburst occurred 55 days after the onset of an accretion outburst in…
Hotspots on the surface of accreting neutron stars have been directly observed via pulsations in the lightcurves of X-ray pulsars. They are thought to occur due to magnetic channelling of the accreted fuel to the neutron star magnetic…
Accreting millisecond pulsars (AMSPs) are excellent laboratories to study reflection spectra and their features from an accretion disk truncated by a rapidly rotating magnetosphere near the neutron star surface. These systems also exhibit…
Many distinct classes of high-energy variability have been observed in astrophysical sources, on a range of timescales. The widest range (spanning microseconds-decades) is found in accreting, stellar-mass compact objects, including neutron…
We calculate steady-state models of radiation-driven super-Eddington winds and static expanded envelopes of neutron stars caused by high luminosities in type I X-ray bursts. We use flux-limited diffusion to model the transition from…
A long flux enhancement, with an exponential decay time of 86 min, is detected in 4U 1735-44 with the BeppoSAX Wide Field Cameras. We argue that this is a type-I X-ray burst, making it the longest such burst ever observed. Current theories…
We describe the evolutionary progression of an outburst of the Rapid Burster. Four outbursts have been observed with the Rossi X-Ray Timing Explorer between February 1996 and May 1998, and our observations are consistent with a standard…
4U 1626-67 is an accretion powered X-ray pulsar that shows remarkably stable X-ray luminosity above hours timescale and gradual intensity variation on a few years timescale. Here we report a significant increase in the X-ray intensity in…
It has been known for nearly three decades that the energy spectra of thermonuclear X-ray bursts are often well-fit by Planck functions with temperatures so high that they imply a super-Eddington radiative flux at the emitting surface, even…
We present a compilation of observed recurrence times ($t_{\rm rec}$) and infer the corresponding local mass-accretion rates ($\dot m$) for type I X-ray bursts, milliHertz quasi-periodic oscillating sources and recurrent novae eruptions. We…
We present a physical framework that can account for most of the observed spectral properties of the prompt gamma-ray burst emission. This includes the variety of spectral shapes, shape evolutions, and spectral correlations between flux and…
GX 3$+$1, an atoll type neutron star low-mass X-ray binary, was observed four times by Soft X-ray Telescope and The Large Area X-ray Proportional Counters on-board \textit{AstroSat} between October 5, 2017 and August 9, 2018. The…