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Description
The variations of kinematic parameters with age are considered for a sample of 15402 thin-disk O-F stars with accurate RA, DEC, proper motion, and parallax higher than 3 mas from the Hipparcos catalogue (2007A&A...474..653V) and radial velocities from the PCRV (2006PAZh...32..844G) catalogue. The ages have been calculated from the positions of the stars on the Hertzsprung-Russell diagram relative to the isochrones from the Padova database (http://stev.oapd.inaf.it/cmd) by taking into account the extinction from the previously constructed 3D analytical model (2009AstL...35..780G) and extinction coefficient RV from the 3D map of its variations (2012AstL...38...12G). Smooth, mutually reconciled variations of the velocity dispersions sigma(U), sigma(V), sigma(W), solar motion components Usun, Vsun, Wsun, Ogorodnikov-Milne model parameters, Oort constants, and vertex deviation lxy consistent with all of the extraneous results for which the stellar ages were determined have been found and presented in the table solution.dat. The velocity dispersion variations are well fitted by power laws the deviations from which are explained by the influence of predominantly radial stellar streams: Sirius, Hyades, alpha Cet/Wolf 630, and Hercules. The accuracy of determining the solar motion relative to the local standard of rest is shown to be fundamentally limited due to these variations of stellar kinematics. The deviations of our results from those of Dehnen and Binney (1998MNRAS.294..429D), the Geneva-Copenhagen survey of dwarfs (V/117), and the Besancon model of the Galaxy (2003A&A...409..523R) are explained by the use of PCRV radial velocities with corrected systematic errors.
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