Related papers: X-ray Orbital Modulations in Intermediate Polars

We report results from long-term (approximately 1240 days) X-ray (0.3-8.0 keV) monitoring of the ultraluminous X-ray source NGC 5408 X-1 with the Swift/X-Ray Telescope. Here we expand on earlier work by Strohmayer (2009) who used only a…

We discover a pronounced dependence of the strength of the X-ray orbital modulation and the hardness in Cyg X-1 in the hard state on its superorbital phase. Our results can be well modelled as a combination of two effects: the precession of…

We investigate the spatial distribution of X-ray emitting plasma in a sample of young Orion Nebula Cluster stars by modulation of their X-ray light-curves due to stellar rotation. The study, part of the Chandra Orion Ultradeep Project…

RXTE observations confirm that the X-ray lightcurve of V2400 Oph is pulsed at the beat cycle, as expected in a discless intermediate polar. There are no X-ray modulations at the orbital or spin cycles, but optical line profiles vary with…

Thanks to long-term X-ray monitoring, a number of interacting binaries are now known to show X-ray periodicities on timescales of tens to hundreds of binary orbits. In some systems, precession of a warped accretion disc is the leading model…

Variation of mass supply rate from the companion can be smeared out by viscous processes inside an accretion disk. By the time the flow reaches the inner edge, the variation in X-rays needs not reflect the true variation of the rate at the…

We present data from long ROSAT HRI observations of the intermediate polars YY Dra and V709 Cas which show that V709 Cas, like YY Dra, exhibits a double-peaked X-ray pulse profile. Neither system shows evidence for X-ray beat period or…

Accreting X-ray pulsars (XRPs) are presumably ideal targets for polarization measurements, as their high magnetic field strength is expected to polarize the emission up to a polarization degree of ~80%. However, such expectations are being…

We present a multi-wavelength timing study of the eclipsing low mass X-ray binary EXO 0748-676 (UY Vol) using XMM-Newton when the source was in a hard spectral state. The orbital optical and X-ray light curves show a fairly large amount of…

As the only eclipsing asynchronous polar, V1432 Aql provides an excellent laboratory to study the interaction between the accreted matter and the magnetic field. Here, we report an analysis of the X-ray data from the contemporaneous…

We investigate the effects of tidally induced asymmetric disc structure on accretion onto the white dwarf in intermediate polars. Using numerical simulation, we show that it is possible for tidally induced spiral waves to propagate…

We present the timing analysis of the intermediate polar TX Col in the X-ray band using the observations made by Chandra, Swift, and Suzaku during the years 2000, 2007, and 2009, respectively. The spin, orbital, and beat periods derived…

We report on the first pointed X-ray observations with XMM-Newton and RXTE satellites of the X-ray source RXJ0757.0+6306=HT Cam. We detect a strong 515s X-ray modulation confirming the optical photometric period found in 1998, which…

It was pointed out by Paczynski (1987) that the X-ray luminosity of accreting neutron stars is very sensitive to the physical properties of the accretion flow close to the innermost stable circular orbit. The X-ray radiation is dominated by…

Millisecond x-ray pulsars have weak magnetic dipole moments of $\sim 10^{16}$\,T\,m$^3$ compared to ordinary X-ray pulsars with dipole moments of $10^{20}$\,T\,m$^3$. For this reason a surrounding accretion disc can extend closer to the…

We present the results of a long-term observation campaign of the extragalactic wind-accreting black-hole X-ray binary LMC X-1, using the Proportional Counter Array on the Rossi X-Ray Timing Explorer (RXTE). The observations show that LMC…

Precessing accretion discs have long been suggested as explanations for the long periods observed in a variety of X-ray binaries, most notably Her X-1/HZ Her. We show that an instability of the disc's response to the radiation reaction…

We present the results of a detailed study of the high mass X-ray binary 2S 0114+650 made with the pointed instruments onboard the Rossi X-ray Timing Explorer. The spectral and temporal behaviour of this source was examined over the pulse,…

Results from spectroscopic observations of the Intermediate Polar (IP) EX Hya in quiescence during 1991 and 2001 are presented. Spin-modulated radial velocities consistent with an outer disc origin were detected for the first time in an IP.…

We present results from a campaign of simultaneous X-ray and optical observations of X1254-690 conducted using the Rossi X-ray Timing Explorer and the CTIO 1.5m telescope. We find that the usually-observed deep X-ray dipping is not seen…