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 < V < 15.5 and in the color index range -0.33 < (B - V) < +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.
Publication Source (Journal or Book title)
Landolt, A. (2007). UBVRI photometric standard stars around the sky at - 50° declination. Astronomical Journal, 133 (6), 2502-2523. https://doi.org/10.1086/518000