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,{{cite journal |title=A New Photometric Technique for the Joint Selection of Star-forming and Passive |journal=The Astrophysical Journal |volume=617 |issue=2 |pages=746–764 |bibcode=2004ApJ...617..746D |last1=Daddi |first1=E. |last2=Cimatti |first2=A. |last3=Renzini |first3=A. |last4=Fontana |first4=A. |last5=Mignoli |first5=M. |last6=Pozzetti |first6=L. |last7=Tozzi |first7=P. |last8=Zamorani |first8=G. |year=2004 |doi=10.1086/425569 |arxiv = astro-ph/0409041 |s2cid=119370438 }} are as follows:

• Star-forming BzK (sBzK) galaxies satisfy: $BzK\; \backslash equiv\; (z-K)\_\{AB\}\; -\; (B-z)\_\{AB\}\; \backslash geq\; -0.2$
• Passive BzK (pBzK) galaxies satisfy: and $(z-K)\_\{AB\}\; >\; 2.5$