Left: Relative amplitude error (see Fig. 2) vs. relative side-lobe amplitudes for the 1061 RRab stars from 12 K2 fields. The straight line corresponds to A_s/A_t = 6 × eA/A, which we identify as the 6σ detection limit in this paper. Right: Injected signal test for the 17 class 0 and class 2 stars in C08 of K2 (blue points). As in Fig. 9, we plot the results for all data sources used in the signal injection test.