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We present observations of the proposed double degenerate polar RX J1914+24. Our optical and infrared spectra show no emission lines. This, coupled with the lack of significant levels of polarisation provide difficulties for a double degenerate polar interpretation. Although we still regard the double degenerate polar model as feasible, we have explored alternative scenarios for RX~J1914+24. These include a double degenerate algol system, a neutron star-white dwarf pair and an electrically powered system. The latter model is particularly attractive since it naturally accounts for the lack of both emission lines and detectable polarisation in RX J1914+24. The observed X-ray luminosity is consistent with the predicted power output. If true, then RX J1914+24 would be the first known stellar binary system radiating largely by electrical energy.
We present XMM-Newton observations of the 569 sec period system RX J1914+24 (V407 Vul). This period is believed to represent the binary orbital period making it an ultra-compact binary system. By comparing the phase of the rise to maximum X-ray flux
The nature of the X-ray source RX J1914+24 has been the subject of much debate. It shows a prominent period of 569 sec in X-rays and the optical/infra-red: in most models this has been interpreted as the binary orbital period. We present our analysis
We have detected the optical counterpart of the proposed double degenerate polar RX J1914+24. The I band light curve is modulated on the 9.5 min period seen in X-rays. There is no evidence for any other periods. No significant modulation is seen in J
On 2017 March 11, the DLT40 Transient Discovery Survey discovered SN 2017cbv in NGC5643, a Type 2 Seyfert Galaxy in the Lupus Constellation. SN 2017cbv went on to become a bright Type Ia supernova, with a $V_{max}$ of 11.51 $pm$ 0.05 mag. We present
Contact binary systems (also known as W UMa systems) consist of a pair of hydrogen-burning dwarf stars orbiting each other so closely that they share a common envelope. Although they are relatively common, there is as yet no established consensus on