AR SCO: THE FIRST WHITE DWARF PULSAR

A recent detection of pulsations with the 1.97 min period, modulated by thebinary period of 3.56 hr, in the radioIRopticalUV synchrotron emission fromthe white dwarf (WD) Mstar binary AR Sco was the first discovery of a WDpulsar powered by WD spindown. Although it is clear that the detected emissionis produced by relativistic particles, the acceleration mechanism and the sitesof emission remain uncertain. To distinguish between different models for theWDpulsar Mstar binary, Xray observations are particularly useful,especially at energies above 10 keV. We propose a NuSTAR observationsupplemented by a short XMMNewton observation to investigate the Xray spectrumand pulsations of AR Sco and infer a realistic model of this unique object. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]