Distances to Cataclysmic Variables using Linear Polarimetry A model independent method is proposed for estimating the distances toCataclysmic Variables (CVs) using linear polarimetry. A polarizationversus distance relation is constructed by measuring the linearpolarization of field stars along the line of sight to the CV. Thedistance of the CV can be estimated by measuring its polarization and byassuming its intrinsic polarization is negligible in relation to theinterstellar polarization, an assumption that appears to be true in mostcases. We show that an accuracy of 6% is achievable by estimating thedistance to VW Hyi to be 82 +- 5 pc. Rough distance estimates of otherCVs with measured polarization are also given. (SECTION: Stars)
Uvby-beta photometry of stars in the Michigan Spectral Catalogue. I - The Delta Del stars uvby-beta photometry of 74 stars classified as Delta Del in Volume 1 ofthe Michigan Spectral Catalogue is presented. The photometry is inagreement with the spectral classification in that it indicates DeltaDel stars are metal-line-enhanced stars with equivalent-temperaturetypes of A9 + or - 2 subtypes. There is a discrepancy between theluminosity implied from the delta c1 index and the spectralclassification. It is argued that c1 is an inadequateluminosity indicator for some late A- to early F-type stars. Several ofthe Delta Del stars are known Delta Scuti pulsators, and some commentson the metallicism-pulsation relation are made.
