Identifying the Elusive Companions in AGB Binaries with Active Accretion

We have identified a sample of AGB stars that are candidates for having binarycompanions with active accretion, via an innovative technique to search for FUVexcesses (fuvAGB stars). We have found variable Xray emission characterized byvery high temperatures (50100 million K) and high luminosities in about 50% ofour sample, implying the presence of variable accretion associated with a closebinary companion. An exciting new result is that for one target (RR Umi) adominant soft Xray component is seen. We hypothesize that the latter is theexpected coronal emission from the mainsequence companion: this hypothesis issupported by RR Umi.s very low FUV variability. We propose to test our hypothesis with a pilot survey of fuvAGB stars with relatively low FUV variability. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]