The Spitzer Adaptation of the Red-sequence Cluster Survey ( SpARCS ) is a deep z ^ { \prime } -band imaging survey covering the Spitzer SWIRE Legacy fields designed to create the first large homogeneously-selected sample of massive clusters at z > 1 using an infrared adaptation of the cluster red-sequence method .
We present an overview of the northern component of the survey which has been observed with CFHT/MegaCam and covers 28.3 deg ^ { 2 } .
The southern component of the survey was observed with CTIO/MOSAICII , covers 13.6 deg ^ { 2 } , and is summarized in a companion paper by Wilson et al .
( 2008 ) .
We also present spectroscopic confirmation of two rich cluster candidates at z \sim 1.2 .
Based on Nod-and-Shuffle spectroscopy from GMOS-N on Gemini there are 17 and 28 confirmed cluster members in SpARCS J163435+402151 and SpARCS J163852+403843 which have spectroscopic redshifts of 1.1798 and 1.1963 , respectively .
The clusters have velocity dispersions of 490 \pm 140 km/s and 650 \pm 160 km/s , respectively which imply masses ( M _ { 200 } ) of ( 1.0 \pm 0.9 ) x 10 ^ { 14 } M _ { \odot } and ( 2.4 \pm 1.8 ) x 10 ^ { 14 } M _ { \odot } .
Confirmation of these candidates as bonafide massive clusters demonstrates that two-filter imaging is an effective , yet observationally efficient , method for selecting clusters at z > 1 .