These data were taken to characterize the performance and test the data acquisition system of two detectors to be used to monitor the stopping target for the forth-coming Mu2e experiment at Fermilab; the High Purity Germanium (HPGe) and Lanthanum Bromide (LaBr) Detectors, in the presence of the pulsed gamma beam at ELBE. This measurement is crucial for the normalisation of the Mu2e experiment. The corresponding beamtime was carried out at the gELBE bremsstrahlung beamline of HZDR's ELBE radiation facility from April 21 to April 25, 2022 (GATE ID: 21202619-ST). The data sets represent the data taken with the LaBr detector by means of an ORTEC DSPEC 50 and a Lecroy/Teledyne HDO4104 oscilloscope.