Color-color and color-magnitude diagrams for the July 2009 data release (Eddie Schlafly)

I've created color-color and color-magnitude diagrams for the July 2009 data release catalogs, with per-exposure zero points taken from comparison with SDSS. The data do better than the SDSS data on the same fields, which is good to see---though this is no surprise, given that each PS magnitude is an average over many PS exposures.

Specifically, I've demanded that each PS object in these plots be detected in all five bands. In practice, this means the following:

band median # of detections
g 15
r 33
i 54
z 36
y 4

The following plots result:

Color-color diagrams

Color-magnitude diagrams

As far as I can tell, we don't yet have a reliable method for discriminating between stars and galaxies in PS. Accordingly, the PS diagrams contain both stars and galaxies, while the my SDSS diagrams contain only stars. The extra locus of objects in the PS diagrams are galaxies.

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