We measure the clustering of extremely red objects (EROs) in ≈8 deg2 of the NOAO Deep Wide Field Survey Bo?tes field in order to establish robust links between ERO (z ≈ 1.2) and local galaxy (z 0.1) populations. Three different color selection criteria from the literature are analyzed to assess the consequences of using different criteria for selecting EROs. Specifically, our samples are (R – Ks ) 5.0 (28, 724 galaxies), (I – Ks ) 4.0?(22, 451?galaxies), and (I – [3.6]) 5.0 (64, 370 galaxies). Magnitude-limited samples show the correlation length (r 0) to increase for more luminous EROs, implying a correlation with stellar mass. We can separate star-forming and passive ERO populations using the (Ks – [24]) and ([3.6] – [24]) colors to Ks = 18.4 and [3.6] = 17.5, respectively. Star-forming and passive EROs in magnitude-limited samples have different clustering properties and host dark halo masses and cannot be simply understood as a single population. Based on the clustering, we find that bright passive EROs are the likely progenitors of 4L* elliptical galaxies. Bright EROs with ongoing star formation were found to occupy denser environments than star-forming galaxies in the local universe, making these the likely progenitors of L* local ellipticals. This suggests that the progenitors of massive 4L* local ellipticals had stopped forming stars by z 1.2, but that the progenitors of less massive ellipticals (down to L*) can still show significant star formation at this epoch.
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