X-ray Observations of Quiescent Recurrent Novae in CVs

For a binary to be a recurrent nova (RN), it must contain a massive white dwarf(WD) near the Chandrasekhar limit, making it a candidate progenitor of type Iasupernova. Although the WD masses and the accretion rates in RNe must all besimilarly high, the Xray properties of RNe with redgiant donar stars can bewildly different, ranging from hard and luminous (virgul1e34 ergs/s) to softer andsignificantly fainter (below 1e32 ergs/s). Such drastic differences may indicatethat a third parameter, such as the spin period or the core temperature of theWD, may play an important role. Here we propose quiescent Xray observations of4 RNe in cataclysmicvariable (CV) systems to test if a third parameter indeedexists. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]