A search for symbiotic activity in CH-stars

We propose to observe 4 CH stars. These are carbonenhanced Population II giantstars nearly all of which have white dwarf binaries, which are responsible fortheir unusual abundances. Based on their orbital parameters, distances, andstellar parameters, we have identified the best candidates for showing Xrayemission. None of these stars has yet been observed by anything more sensitivethan ROSAT, but we anticipate that they should be detectable in a modest amountof XMM time. Discovering Xray emission will open up a new understanding of thestellar winds from these stars, and of the otherwise hardtomeasure masses oftheir white dwarfs. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]