<i>UBVRI</i>PHOTOMETRIC STANDARD STARS AROUND THE SKY AT +50 deg DECLINATION

Abstract

Cerro Tololo Inter-American Observatory, National Optical Astronomical Observatory UBVRI photoelectric observations have been made of 109 stars around the sky, centered more or less at -50° declination. The majority of the stars fall in the magnitude range 10.4 &lt; V &lt; 15.5 and in the color index range -0.33 &lt; (B - V) &lt; +1.66. These new broadband photometric standard stars average 16.4 measurements each from data taken on 116 different nights over a period of 4 yr. Similar data are tabulated for 19 stars of interest that were not observed often enough to make them well-defined standard stars. © 2007. The American Astronomical Society. All rights reserved.