The ESO-Max Planck photometric and spectroscopic survey in the south: EMPhaSSiS

Abstract

EMPhaSSiS is a photometric and spectroscopic survey of the disk of the Milky Way. The survey covers 33 fields in the 3rd quadrant of the Milky Way and probes every ten degrees in Galactic Longitude between l = 180∘ - 280∘ and at Galactic Latitudes of b = −20∘, − 30∘ and − 40∘. Each field is observed in four filters, U, B, V and R, reaching depths of 21.5, 24.0, 23.5 and 23.5 respectively. Spectroscopic observations have been carried out in 11 of these fields and in so doing, main sequence turn-off stars are being traced into the outer disk. This survey will provide metallicities and distances to the stellar populations that reside in the very outer disk of the Milky Way and help trace its evolution with increasing Galactic radius.