Gaia-ASAS-SN classical Cepheid sample. I.

We first use parallax and variability information from Gaia to select ~30000 bright (G<17) Cepheid candidates with M_K_{<}-1. We then analyze their ASAS-SN V-band light curves, determining periods and classifying the light curves using their Fourier parameters.

This results in ~1900 likely Galactic Cepheids, which we estimate to be >~90% complete and pure within our adopted selection criteria. This is the largest all-sky sample of Milky Way Cepheids that has such a well-characterized selection function, needed for population modeling and for systematic spectroscopic follow-up foreseen with Sloan Digital Sky Survey-V. About 130 of these potential Cepheids have not been documented in the literature even as possible candidates.