Wide range automatic energy calibration of LaBr 3: Ce detectors by the self-activity lines

A real-time automatic energy calibration (RAEC) algorithm of a LaBr3:Ce scintillation detector array has been developed. The energy markers for this calibration are the self-activity lines inherently existing inside the LaBr3 crystal. Five energy markers were used in this technique. Two lines are from the radioactive isotope of lanthanum, 138La, at 789 and 1436 keV while the other three are from the 227Ac which is thought to be the source of the self-activity of LaBr3 detectors near 2 MeV energy range. The energy calibration extracted from RAEC algorithm is evaluated by a comparison with the energy calibration that was established using 56Co radioactive checking source. The two energy calibrations showed a good agreement, indicating a high potential to use the self-energy calibration technique for LaBr3:Ce detectors.