BzK galaxy

In astrophysics, a BzK galaxy is a galaxy that has been selected as star-forming or passive based on its photometry in the B, z, and K photometric bands.

The selection criteria, as originally defined, are as follows:
 * Star-forming BzK (sBzK) galaxies satisfy: $$ BzK \equiv (z-K)_{AB} - (B-z)_{AB} \geq -0.2$$
 * Passive BzK (pBzK) galaxies satisfy: $$ BzK < -0.2$$ and $$(z-K)_{AB} > 2.5$$