Galaxy rotation curve from classical Cepheids
  The Galaxy rotation curve is usually assumed to be flat. However, some
galaxies have rotation curves that are lower than the flat rotation curve. In
our Galaxy the Keplerian rotation of interstellar clouds in the galactic
longitude l=135 was observed.
  We use a kinematic approach to derive the rotational velocity of classical
Cepheids. The rotational velocity was calculated from radial velocity and from
proper motion. The derived rotational velocities of Cepheids are between
Keplerian rotation and the flat one. We fit a Galaxy rotation model consisting
of a black hole, bulge, disk and halo to the rotation curve. The density of
dark matter halo is at least 60% less than the value obtained from the flat
rotation curve.
