Left: color–magnitude diagram for stars within R ≤ 0.°5 of the center of Crater 2 (Torrealba et al. 2016, “T16”). The red line shows the Dartmouth isochrone (Dotter et al. 2008) for age = 12 Gyr, [Fe/H] = −1.7, [α/Fe] = +0.4, and distance modulus m − M = 20.3. Right: positions for stars photometrically selected as red giant branch candidates. The black circle marks the 2D halflight radius measured by T16. In both panels, filled red/black circles represent probable members/nonmembers in our Hectochelle spectroscopic catalog (see Section 4.2); black “x”s mark stars with spectra that did not pass quality-control criteria.