Galactic Cepheids abundance variations

These Cepheids extend previous samples by about 35% in number and increase the amount of the Galactic disk coverage especially in the direction of l~~270{deg}. The new Cepheids do not add much information to the radial gradient, but provide a substantial increase in azimuthal coverage.

We find no azimuthal dependence in abundance over an 80{deg} angle from the Galactic center in an annulus of 1kpc depth centered on the Sun. A simple linear fit to the Cepheid data yields a gradient d[Fe/H]/dR_G_=-0.055+/-0.003dex/kpc which is somewhat shallower than found from our previous, smaller Cepheid sample.