THE K-BAND SURFACE BRIGHTNESS OF LATE-TYPE STARS AND THE DISTANCE TO CATACLYSMIC VARIABLES

The method for determining the distance to cataclysmic variables using the K-band surface brightness is reexamined with a new, larger dataset. The K-band surface brightness of dwarf stars is constant over the range 3.0 less-than-or-equal-to V - K less-than-or-equal-to 5.0, and declines at larger values of V - K. The behavior of the K-band surface brightness depends on luminosity class. Theoretical models of M dwarf stars are roughly consistent with the observations. This new surface brightness relationship reconciles the different distance determinations for HT Cas.