Mean angular power spectra of the full sample LRG autocorrelation (left panels) and LRG-CMB lensing cross-correlation (right panels), computed from the 100 mock realizations used to test our pipeline for various values of f_NL (−50 top panels, 0 middle panels, and 50 bottom panels). The blue lines show the true angular power spectra before adding contamination, the shaded blue area corresponds to the dispersion on the true spectra, the orange lines correspond to the angular power spectra of the contaminated mocks, and the green lines to the contaminated mocks after imaging systematics mitigation.