THE NATURE OF THE ACCRETING OBJECT IN HD 161103 AND SAO 49725

ROSAT observations have shown that the Be stars HD 161103 and SAO 49725 exhibitan excess of Xray emission over the normal shocked wind component. Therelatively modest Xray luminosity of about 1 to 5 E32 erg/s (0.22.4 keV) isconsistent with that expected from a white dwarf accreting from the equatorialdisc of a Be star. Whereas models predict that they should outnumber Be +neutron star binaries by a factor of about 10, no Be + white dwarf system hasever been confirmed so far. This absence casts some doubts on our currentunderstanding of massive Xray binary evolution. The goal of the proposedobservation is to characterize the Xray spectral and temporal properties ofthese Xray emitters and search for the signatures of an accreting white dwarf. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]