Reference

The list below is one of the standard starlists available at Keck and is called: 0000_landolt.std.big

Abstract

The Landolt (1992) UBVRI photometric standard stars list features several fields which contain multiple standard stars, allowing standards over a range of colors to be measured in a single exposure. The following table lists several of these useful ``bonus fields''. These bonus fields have RA and Dec values that maximize the number standards in an LRIS field which is listed in the last column of the table.

UBVRI photoelectric observations have been made on the Johnson-Kron-Cousins photometric system of 526 stars centered on the celestial equator. The program stars within a 298 number subset have sufficient measures that they are capable of providing, for telescopes of intermediate and large size in both hemispheres, an internally consistent homogeneous broadband standard photometric system around the sky. The stars average 29 measures each on 19 nights. The majority of the stars in this paper fall in the magnitude range 11.5 < V < 16.0, and in the color range -0.3 < (B-V) < +2.3.

Remember that for short exposures the shutter "fly time" may dominate the photometric accuracy of your result. One way around this is to define a set of "secondary" standards in the field which are relatively fainter than the standards given below. A short (1 s) combined with a longer (10 s) could be taken. The ratio of fluxes of the faint stars in the short and long exposures is the ratio of the effective exposure times. The ratio may be used to correct standard fluxes at the edge of the field in the short (1 s) exposure. Note that as long as the exposures are taken with the same filter there is no need to know the colors of the fainter field stars.

Data

Notes on Star Designations:

• TPHE = stars in the vicinity of T Phe ; (note that TPHE B = SW Phe)
• F = Feige
• PG = Palomar Green
• Two numbers indicate the "Durchmusterung of Selected Areas" (Harvard Annals 101)