Program: GN-2010B-Q-76

Cataclysmic variables are common and structurally simple binaries in which a white dwarf accretes from a low-mass companion. As such, they are an excellent benchmark population to test, calibrate, and further develop binary population synthesis models. These models are used in a wide range of contexts including the formation of binary pulsars and analysing the observed mixture of short/long delay SN Ia. The Sloan Digital Sky Survey (SDSS) produced the deepest and most homogenous CV sample to date, and has led to a number of fundamental results. However, the spectroscopic completeness of the SDSS spectroscopy plummets below i = 19.1, and it is exactly in this range that the composition of the Galactic CV population undergoes a major change. Towards fainter magnitudes the fraction of low-luminosity systems increase and probably dominate the space density of CVs. We propose to extend the depth of the SDSS CV sample by obtaining Gemini N & S GMOS observations of faint CV candidates in the SDSS footprint identified by outbursts in the Catalina Real Time Transient Survey .