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View article: XMM-Newton observations of eleven intermediate polars and possible candidates
XMM-Newton observations of eleven intermediate polars and possible candidates Open
Aims. We aim to identify new intermediate polars (IPs) in XMM-Newton observations from a list of promising candidates. By selecting targets not previously known to be X-ray bright, we aim to uncover evidence for an X-ray underluminous IP s…
View article: Identification of 3XMM J000511.8+634018 as a new polar at <i>P</i><sub>orb</sub> = 133.5 min – is it inside or outside the period gap?
Identification of 3XMM J000511.8+634018 as a new polar at <i>P</i><sub>orb</sub> = 133.5 min – is it inside or outside the period gap? Open
Aims. We aimed to identify the variable X-ray source 3XMM J000511.8+634018, which was serendipitously discovered through routine inspections while the 3XMM catalogue was compiled. Methods. We analysed the archival XMM-Newton observation of…
View article: <scp>MACHO</scp> 311.37557.169: A <scp>VY</scp> Scl star
<span>MACHO</span> 311.37557.169: A <span>VY</span> Scl star Open
Optical surveys, such as the MACHO project, often uncover variable stars whose classification requires follow‐up observations by other instruments. We performed X‐ray spectroscopy and photometry of the unusual variable star MACHO 311.37557…
View article: V902 Monocerotis: A likely disc-accreting intermediate polar
V902 Monocerotis: A likely disc-accreting intermediate polar Open
\nAims. We aim to confirm whether the eclipsing cataclysmic variable (CV) V902 Mon is an intermediate polar (IP), to characterise its X-ray spectrum and flux, and to refine its orbital ephemeris and spin period.\nMethods. We performed spec…
View article: X-ray and optical observations of polars
X-ray and optical observations of polars Open
The soft excess is a spectral feature shown by many polar cataclysmic variables, resembling a very luminous blackbody in soft X-rays. It is thought to arise from the accretion of discrete blobs of gas onto the WD, and was found in all pola…
View article: Neutron star cooling and the rp process in thermonuclear X-ray bursts
Neutron star cooling and the rp process in thermonuclear X-ray bursts Open
When the upper layer of an accreting neutron star experiences a thermonuclear runaway of helium and hydrogen, it exhibits an X-ray burst of a few keV with a cool-down phase of typically 1 min. When there is a surplus of hydrogen, hydrogen …
View article: Radiation drag on the accretion disc in type-I X-ray bursts
Radiation drag on the accretion disc in type-I X-ray bursts Open
Type I X-ray bursts on accreting neutron stars offer a means to probe the interior of these stars by providing information about the conditions at its surface, via the measurement of radius and surface gravitational redshift. Our understan…
View article: X-ray and optical observations of four polars
X-ray and optical observations of four polars Open
We aim to study the temporal and spectral behaviour of four polar CVs from the infrared to X-ray regimes, refine our knowledge of the physical parameters of these systems at different accretion rates, and to search for a possible excess of…