“…The Sloan Digital Sky Survey (SDSS) is a joint project of the University of Chicago, Fermilab, the Institute for Advanced Study, the Japan Participation Group, The Johns Hopkins University, the Max-Planck-Institute for Astronomy, Princeton University, the United States Astrometry is given in J2000 coordinates. Photometry is reported in terms of asinh magnitudes, which smoothly goes to a linear scale in the limits of low signal-to-noise ratio; see Lupton, Gunn & Szalay (1999) and Fan et al (1999a) for details. The u * , g * , and r * values all represent non-detections (for comparison, in our system, zero flux corresponds to 24.24, 24.91, 24.53, 23.89, and 22.47, in u * , g * , r * , i * , and z * , respectively).…”