Population types of cataclysmic variables in the solar neighbourhood
  The Galactic orbital parameters of 159 cataclysmic variables in the Solar
neighbourhood are calculated, for the first time, to determine their population
types using published kinematical parameters. Population analysis shows that
about 6 per cent of cataclysmic variables in the sample are members of the
thick disc component of the Galaxy. This value is consistent with the fraction
obtained from star count analysis. The rest of the systems in the sample are
found to be in the thin disc component of the Galaxy. Our analysis revealed no
halo CVs in the Solar vicinity. About 60 per cent of the thick disc CVs have
orbital periods below the orbital period gap. This result is roughly consistent
with the predictions of population synthesis models developed for cataclysmic
variables. A kinematical age of 13 Gyr is obtained using total space velocity
dispersion of the most probable thick disc CVs which is consistent with the age
of thick disc component of the Galaxy.
