Abstract
We use cosmic microwave background (CMB) temperature maps from the 500 deg2 SPTpol survey to measure the stacked lensing convergence of galaxy clusters from the Dark Energy Survey (DES) Year-3 redMaPPer (RM) cluster catalog. The lensing signal is extracted through a modified quadratic estimator designed to be unbiased by the thermal Sunyaev鈥揨el'dovich (tSZ) effect. The modified estimator uses a tSZ-free map, constructed from the SPTpol 95 and 150 GHz data sets, to estimate the background CMB gradient. For lensing reconstruction, we employ two versions of the RM catalog: a flux-limited sample containing 4003 clusters and a volume-limited sample with 1741 clusters. We detect lensing at a significance of 8.7蟽(6.7蟽) with the flux (volume)鈥搇imited sample. By modeling the reconstructed convergence using the Navarro鈥揊renk鈥揥hite profile, we find the average lensing masses to be ${M}_{200{\rm{m}}}=({1.62}_{-0.25}^{+0.32}\,[\mathrm{stat}.]\pm 0.04\,[\mathrm{sys}.])$ and $({1.28}_{-0.18}^{+0.14}\,[\mathrm{stat}.]\pm 0.03\,[\mathrm{sys}.])$ $\times {10}^{14}\,{M}_{\odot }$ for the volume- and flux-limited samples, respectively. The systematic error budget is much smaller than the statistical uncertainty and is dominated by the uncertainties in the RM cluster centroids. We use the volume-limited sample to calibrate the normalization of the mass-richness scaling relation, and find a result consistent with the galaxy weak-lensing measurements from DES.