“…Single-stage qPAT with multiple illuminations has been studied in [27,38,42,9,60]. Moreover, multiple illuminations have been proposed in several mathematical works to stabilize various inverse problems with internal data (e.g., [12,11,7,10,13,57,64,81]). For each illumination and measurement, we denote by H i := H f i ,q i and W i := W Λ i ,T the corresponding heating and acoustic operator and by F i = W i • H i the resulting forward operator.…”