ИСТИНА

The wavelike oscillations of the vertical scale height of the local population of classical Cepheids located at Galactocentric distances R0 - 1kpc < Rg, < R0 + 1 kpc is analyzed using Cepheid ages computed in terms of evolutionary models of Pols et al. (1998) wiith and without the allowance for convective overshooting. The resulting periods of vertical oscillations of stars about the galactic plane are dound to be PZ = 74±2 Myr and PZ = 104±2 Myr for standard models and models with overshooting, respectively. If interpreted as a manifestation of vertical viral oscillations, the parrern found implies local mass density values of ρ1std = 0.118 ± 0.007 Solar Masses pc-3 and ρovs = 0.060±0.004 Solar Masses pc-3, respectively. The latter value is totally incompatible with recent estimates based on Hipparcos data and the former value, combines with recent estimates of the local density of visible matter, sets an upper limit of 0.023 Solar Masses pc-3 for the local density of dark matter.