X-ray nova candidates among old classical novae

A review of light curves of known x-ray novae made it possible to identify criteria by which x-ray nova candidates were selected among old novae: amplitude of optical outburst 7–10 ^m, shape of light curve during the outburst with a temporary fading by 2–3^m lasting up to four days and an abrupt final fading from the 6^m level (relative to the quiet state). We identified LS And, AL Com, V592 Her, and HV Vir as x-ray nova candidates. Recurrent outbursts should be expected for the first and third stars. Less reliable candidates are V341 Nor, V787 Sgr, and V719 Sco. A possible recurrent nova candidate may be V1330 Cyg. Translated from Astrofizika, Vol. 42, No. 3, pp. 359–364, July–September, 1999.