This catalog is a tab-spaced ASCII
table in the Starbase
data table format. It was created with the following steps:
Select photometric quality flags A or B, reject photometric quality
flags D, E, F, U, or X (objects with poor or non-existent photometry).
Reject objects with contamination flags p, d, s, and b (objects
contaminated by nearby bright stars or other objects, as well as CCD
artifacts).
Reject all objects in the region of the Galactic plane -15 < b < 15
deg.
Select on magnitude 12.5 < J_0 < 15.5 mag.
Select on color -0.20 < (J-H)_0 < 0.10 mag.
Select on color -0.10 < (H-K)_0 < 0.10 mag.
Spectroscopic identification finds that the color-selected objects are
47% BHB stars, 39% A-type stars, and 14% miscellaneous objects (mostly
early F-types). The following plot shows spatial distribution, in
Galactic coordinates, of the BHB candidates in three apparent magnitude
bins.