相关论文: XMM-Newton observations of the asynchronous polar …
Context. The energy balance of cataclysmic variables with strong magnetic fields is a central subject in understanding accretion processes on magnetic white dwarfs. With XMM-Newton, we perform a spectroscopic and photometric study of soft…
Context. On the basis of XMM-Newton observations, we investigate the energy balance of selected magnetic cataclysmic variables, which have shown an extreme soft-to-hard X-ray flux ratio in the ROSAT All-Sky Survey. Aims. We intend to…
We report on X-ray spectroscopic observations with XMM/Newton of the ultracompact, double white dwarf binary, GP Com. With the Reflection Grating Spectrometers (RGS) we detect the Lyman alpha and beta lines of hydrogen-like nitrogen (N VII)…
We present an analysis of the X-ray spectra of two strongly magnetic cataclysmic variables, DP Leo and WW Hor, made using XMM-Newton. Both systems were in intermediate levels of accretion. Hard optically thin X-ray emission from the shocked…
We review the X-ray spectral properties of magnetic cataclysmic binaries derived from observations obtained during the last decade with the large X-ray observatories XMM-Newton, Chandra and Suzaku. We focus on the signatures of the…
We present phase-resolved XMM_Newton data of three short period polars: V347 Pav, GG Leo and EU UMa. All three systems show one dominant accretion region which is seen for approximately half of the orbital cycle. GG Leo shows a strong dip…
We have made a series of snap-shot observations of 37 polars using XMM-Newton. We found that 16 of these systems were in a low, or much reduced, accretion state. Of those, 6 were not detected in X-rays. This suggests that in any survey of…
XMM-Newton was used to observe two eclipsing, magnetic cataclysmic variables, DP Leo and WW Hor, continuously for three orbital cycles each. Both systems were in an intermediate state of accretion. For WW Hor we also obtained optical light…
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…
RS Cae is the third target in our series of XMM-Newton observations of soft X-ray-dominated polars. Our observational campaign aims to better understand and describe the multiwavelength data, the physical properties of the system…
We make a systematic analysis of the XMM-Newton X-ray spectra of intermediate polars (IPs) and find that, contrary to the traditional picture, most show a soft blackbody component. We compare the results with those from AM Her stars and…
High-energy data of accreting white dwarfs give access to the regime of the primary accretion-induced energy release and the different proposed accretion scenarios. We perform XMM-Newton observations of polars selected due to their ROSAT…
We report follow-up XMM-Newton and optical observations of three new polars found in the Sloan Digital Sky Survey. Simple modeling of the X-ray spectra, and consideration of the details of the X-ray and optical lightcurves corroborate the…
White dwarf symbiotic binaries are detected in X-rays with luminosities in the range of 10$^{30}$ to 10$^{34}$ lumcgs. Their X-ray emission arises either from the accretion disk boundary layer, from a region where the winds from both…
The intermediate polar PQ Geminorum shows a complex pulsation, caused by a spinning white dwarf, which varies markedly with wavelength. We report XMM-Newton observations, including the soft and hard X-ray bands and the first UV lightcurves…
We report on XMM-Newton observations of the galactic supersoft X-ray source RX J0925.7-4758. The RGS spectrum exhibits a wealth of spectral features from iron and oxygen. XMM-Newton data confirm the finding of previous Chandra HETGS/MEG…
A cataclysmic variable is a binary system consisting of a white dwarf that accretes material from a secondary object via the Roche-lobe mechanism. In the case of long enough observation, a detailed temporal analysis can be performed,…
Using XMM-Newton we have obtained the first X-ray observation covering a complete orbit of the longest period polar, V1309 Ori. The X-ray light curve is dominated by a short, bright phase interval with EPIC pn count rates reaching up to 15…
We present results from the XMM observations of the dwarf nova YZ Cnc in a quiescent state. We have performed a detailed time series analysis of the resulting light curves. Unusually, we do not detect any orbital modulation in the UV, with…
We present the results of XMM-Newton observations of four AM CVn systems -- AM CVn, CR Boo, HP Lib and GP Com. Their light curves show very different characteristics. The X-ray light curves show no coherent pulsations, suggesting the…