The Star-Formation History of BCGs to z = 1.8 from the SpARCS/SWIRE Survey: Evidence for significant in-situ star formation at high-redshift

We present the results of an MIPS-24 μm study of the brightest cluster galaxies (BCGs) of 535 high-redshift galaxy clusters. The clusters are drawn from the Spitzer Adaptation of the Red-Sequence Cluster Survey, which effectively provides a sample selected on total stellar mass, over 0.2 12) increases rapidly with redshift. Above z ~ 1, an average of ~20% of the sample have 24 μm inferred infrared luminosities of L_(IR) > 10^(12) L_⊙, while the fraction below z ~ 1 exhibiting such luminosities is