We present a catalog of galaxy clusters selected via their Sunyaev-Zel ’ dovich ( SZ ) effect signature from 2500 deg ^ { 2 } of South Pole Telescope ( SPT ) data .
This work represents the complete sample of clusters detected at high significance in the 2500 deg ^ { 2 } SPT-SZ survey , which was completed in 2011 .
A total of 677 ( 409 ) cluster candidates are identified above a signal-to-noise threshold of \xi = 4.5 ( 5.0 ) .
Ground- and space-based optical and near-infrared ( NIR ) imaging confirms overdensities of similarly colored galaxies in the direction of 516 ( or 76 \% ) of the \xi > 4.5 candidates and 387 ( or 95 \% ) of the \xi > 5 candidates ; the measured purity is consistent with expectations from simulations .
Of these confirmed clusters , 415 were first identified in SPT data , including 251 new discoveries reported in this work .
We estimate photometric redshifts for all candidates with identified optical and/or NIR counterparts ; we additionally report redshifts derived from spectroscopic observations for 141 of these systems .
The mass threshold of the catalog is roughly independent of redshift above z \sim 0.25 leading to a sample of massive clusters that extends to high redshift .
The median mass of the sample is \mbox { $M _ { \mbox { \scriptsize 500 c } } $ } ( \rho _ { \mathrm { crit } } ) \sim 3.5 \times 10 ^ { 14 } M _ { \odot } h _ { 70 } ^ { -1 } , the median redshift is z _ { \mathrm { med } } = 0.55 , and the highest-redshift systems are at z > 1.4 .
The combination of large redshift extent , clean selection , and high typical mass makes this cluster sample of particular interest for cosmological analyses and studies of cluster formation and evolution .