Mean ΔSFR_fr for galaxies grouped by bar strength (rows) and merger history (columns), plotted against look-back time for different radial bins. Each column shows a distinct merger epoch: early (>8 Gyr ago), middle (4-8 Gyr ago), and late (<4 Gyr ago). The x-axis is centered on the time of the merger, with 0 marking the merger event. Negative values correspond to look-back time before the merger, and positive values indicate time after the merger, measured in Gyr. Colored lines correspond to six radial bins in units of h_d, and shaded circles represent the magnitude of ΔSFR, highlighting the extent of radial migration before and after mergers. A completeness threshold is applied, where a point is shown only if at least 35% of galaxies in that merger history group have nonzero SFR_Birth in the corresponding age bin.