UBVRI standards around celestial equator

These stars constitute both an update of and additions to a previously published list of equatorial photometric standard stars. The list is capable of providing, for both celestial hemispheres, an internally consistent homogeneous broadband standard photometric system around the sky.

When these new measurements are included with those previously published by Landolt (1992, Cat. II/183), the entire list of standard stars in this paper encompasses the magnitude range 8.90<V<16.30, and the color index range -0.35<(B-V)<+2.30.