Related papers: Supersoft X-ray Sources. Basic Parameters
ROSAT spectra of 11 supersoft X-ray sources (RX J0439.8-6809, RX J0513.9-6951, RX J0527.8-6954, CAL 87, CAL 83, 1E 0035.4-7230, RX J0048.4-7332, 1E 0056.8-7154, RX J0019.8 +2156, RX J0925.7-4758, AG Draconis) are approximated with…
Supersoft X-ray sources are commonly believed to be stably burning white dwarfs. However, the observations of some supersoft sources show dramatic variability of their X-ray flux on timescales ranging from days to years. Here, we present…
Supersoft X-ray sources (SSSs) are accreting white dwarfs (WDs) with stable or recurrent thermonuclear burning on their surfaces. High-resolution X-ray spectra of such objects are rather complex, often consist of several components, and are…
The Super Soft Source RX J0925.7--4758 was observed by BeppoSAX LECS and MECS on January 25--26 1997. The source was clearly detected by the LECS but only marginally detected by the MECS. We apply detailed Non-Local Thermodynamic…
Super Soft X-ray Sources (SSS) are powered by nuclear burning on the surface of an accreting white dwarf, they are seen around 0.1-1 keV (thus in the soft X-ray regime), depending on effective temperature and the amount of intervening…
Supersoft X-ray sources (SSS) are thought to be accreting white dwarfs (WDs) in close binary systems, with thermonuclear burning on their surfaces. The SSS RX J0513.9-6951 in the Large Magellanic Cloud (LMC) exhibits cyclic variations…
The highly luminous (> 10^37 erg s^-1) supersoft X-ray sources (SSS) are believed to be Eddington limited accreting white dwarfs undergoing surface hydrogen burning. The current paradigm for SSS involves thermally unstable mass transfer…
We present further observational data of the supersoft X-ray source RX J0527.8-6954 exhibiting a continuous decline over the past 5 yrs. With no clear trend of a concordant temperature decrease this might suggest an evolutionary scenario…
About 200 X-ray sources from a sample of spectrally hard ROSAT PSPC sources, given in the catalog of Haberl & Pietsch (1999), and observed in a ~60 square degree field of the LMC during several archival pointed observations with a wide…
We introduce a procedure to identify very soft X-ray sources (VSSs) in external galaxies. Our immediate goal was to formulate a systematic procedure to identify luminous supersoft X-ray sources (SSSs), so as to allow comparisons among…
We present spectroscopy and photometry of the LMC supersoft binary system RX~J0513.9-6951. We derive a refined spectroscopic period of P$=0.761\pm0.004$~d, which is consistent with the value obtained from long term photometric monitoring…
We report observation results of the super-soft X-ray sources (SSS) CAL87 and RXJ0925.7-4758 with the X-ray CCD cameras (Solid-state Imaging Spectrometer; SIS) on-board the ASCA satellite. We have applied theoretical spectral models to…
We have conducted a systematic search for supersoft X-ray sources using the ROSAT all-sky survey data. With the optical identification of the selected sources being almost complete, we discuss the statistics of the various source classes…
A Chandra ACIS-S imaging observation of the nearby galaxy M81 (NGC 3031) reveals 9 luminous soft X-ray sources. The local environments, X-ray spectral properties, and X-ray light curves of the sources are presented and discussed in the…
The class of Super Soft Sources has been established after discoveries performed with the Einstein and the ROSAT satellite. Only sources contributing to the class of super-soft X-ray binaries are considered. The X-ray emission in these…
The absolute calibration of space-borne instruments in the soft X-ray regime rests strongly on model spectra of hot white dwarfs. We analyze the Chandra LETG+HRC-S observations of the white dwarfs HZ43 A and Sirius B and of the neutron star…
We present new results of our X-ray monitoring of the transient binary supersoft X-ray source RX J0513.9-6951 in the LMC and of our re-analysis of optical light curves obtained during the MACHO project. We have covered a complete X-ray…
Supersoft X-ray sources (SSS) have been identified as white dwarfs accreting from binary companions and undergoing nuclear-burning of the accreted material on their surface. Although expected to be a relatively numerous population from both…
We report on a BeppoSAX Concentrator Spectrometer observation of the super-soft source (SSS) CAL87. The X-ray emission in SSS is believed to arise from nuclear burning of accreted material on the surface of a white dwarf (WD). An absorbed…
Nova LMC 1995, previously detected during 1995-1998 with ROSAT, was observed again as a luminous supersoft X-ray source with XMM-Newton in December of 2000. This nova offers the possibility to observe the spectrum of a hot white dwarf,…