Cleaned USNO-B Catalog: The USNO-B Catalog of astrometric standards contains about 2 percent spurious entries that are caused by diffraction spikes and circular reflection halos around bright stars in the original imaging data. We used computer vision techniques to identify and remove them. Information about getting the clean catalog is available here.
Quad index files: If you have obtained our code and are
seeking the index files necessary to run it, see the instructions at
our use the code
page.