Aims. To determine the credentials of nine candidate intermediate polars in order to confirm whether or not they are magnetic cataclysmic variables. Methods. Frequency analysis of RXTE and XMM data was used to search for temporal variations which c
ould be associated with the spin period of the magnetic white dwarf. X-ray spectral analysis was carried out to characterise the emission and absorption properties of each target. Results. The hard X-ray light curve of V2069 Cyg shows a pulse period of 743.2 s, and its spectrum is fit by an absorbed bremsstrahlung model with an iron line, confirming this to be a genuine intermediate polar. The hard X-ray light curve of the previously confirmed intermediate polar IGR J00234+6141 is shown to be consistent with the previous low energy X-ray detection of a 563.5 s pulse period. The likely polar IGR J14536-5522 shows no coherent modulation at the previously identified period of 3.1 hr, but does exhibit a clear signal at periods likely to be harmonically related to it. Whilst our RXTE observations of RX J0153.3+7447, Swift J061223.0+701243.9, V436 Car and DD Cir are largely too faint to give any definitive results, the observation of IGR J16167-4957 and V2487 Oph show some characteristics of intermediate polars and these objects remain good candidates. Conclusions. We confirmed one new hard X-ray selected intermediate polar from our sample, V2069 Cyg.
The WASP (Wide Angle Search for Planets) project is an exoplanet transit survey that has been automatically taking wide field images since 2004. Two instruments, one in La Palma and the other in South Africa, continually monitor the night sky, buildi
ng up light curves of millions of unique objects. These light curves are used to search for the characteristics of exoplanetary transits. This first public data release (DR1) of the WASP archive makes available all the light curve data and images from 2004 up to 2008 in both the Northern and Southern hemispheres. A web interface (www.wasp.le.ac.uk/public/) to the data allows easy access over the Internet. The data set contains 3 631 972 raw images and 17 970 937 light curves. In total the light curves have 119 930 299 362 data points available between them.
Context. The origin, evolution, and ultimate fate of magnetic cataclysmic variables are poorly understood. It is largely the nature of the magnetic fields in these systems that leads to this poor understanding. Fundamental properties, such as the fie
ld strength and the axis alignment, are unknown in a majority of these systems. Aims. We undertake to put all the previous circular polarization measurements into context and systematically survey intermediate polars for signs of circular polarization, hence to get an indication of their true magnetic field strengths and try to understand the evolution of magnetic cataclysmic variables. Methods. We used the TurPol instrument at the Nordic Optical Telescope to obtain simultaneous UBVRI photo-polarimetric observations of a set of intermediate polars, during the epoch 2006 July 31 - August 2. Results. Of this set of eight systems two (1RXS J213344.1+510725 and 1RXS J173021.5-055933) were found to show significant levels of circular polarization, varying with spin phase. Five others (V2306 Cyg, AO Psc, DQ Her, FO Aqr, and V1223 Sgr) show some evidence for circular polarization and variation of this with spin phase, whilst AE Aqr shows little evidence for polarized emission. We also report the first simultaneous UBVRI photometry of the newly identified intermediate polar 1RXS J173021.5-055933. Conclusions. Circular polarization may be ubiquitous in intermediate polars, albeit at a low level of one or two percent or less. It is stronger at longer wavelengths in the visible spectrum. Our results lend further support to the possible link between the presence of soft X-ray components and the detectability of circular polarization in intermediate polars.
