SUMMARY OF PROPOSAL 43011 DR MICHAEL G WATSON UNIVERSITY OF LEICESTER UK LE1 7RH LEICESTER UNIVERSITY ROAD E-mail: MGW@STAR.LE.AC.UK Tel: +44 116 252 3553 Fax: +44 116 252 3311 Medium: 4GBDAT Subject: CATACLYSMIC VARIABLES Title: HARD X-RAYS FROM THE EUV TRANSIENT SOURCE RE J1255+266 Abstract: The EUV transient source RE~J1255+266 was, temporarily, the brightest object in the EUV sky in 1994. We have now identified this system with a 18 mag. emission line star. A follow-up optical study suggests RE~J1255+266 may be an accretion-powered system, i.e. a cataclysmic variable which should, by analogy with related systems, have a detectable hard flux in quiescence. The ASCA observation we propose will provide the first hard X-ray data on this object. ASCA X-ray spectroscpy will provide a powerful diagnostic of the accretion processes taking place in this unusual system, since the spectrum is expected to be dominated by thermal X-ray emission. Co-Is: 1 MANABU ISHIDA ISAS JAPAN (No Co-I contact data) Target Name PRI RA Dec Time TC Off GIS SIS_Cts Obs ------------------- --- -------- -------- ---- -- --- --- ------- --- RE J1255+266 1 193.7946 26.7078 20 N N P 0.10000 1