Strömgren photometric survey in the Galactic anticenter direction

Abstract

Aims. The main purpose is to map the radial variation of the stellar space density for the young stellar population in the Galactic anticenter direction in order to understand the structure and location of the Perseus spiral arm. Methods. A uvbyHβ Strömgren photometric survey covering 16 deg 2 in the anticenter direction was carried out using the Wide Field Camera at the Isaac Newton Telescope. This is the natural photometric system for identifying young stars and obtaining accurate estimates of individual distances and ages. The calibration to the standard system was undertaken using open clusters. Results. We present a main catalog of 35 974 stars with all Strömgren indexes and a more extended one with 96 980 stars with partial data. The central 8 deg2 have a limiting magnitude of V ∼ 17 m, while the outer region reaches V ∼ 15.m5. These large samples will permit us to analyze the stellar surface density variation associated to the Perseus arm also to study the properties of the stellar component and the interstellar extinction in the anticenter direction. © 2012 ESO.