Internal bremsstrahlung from89Sr

The internal bremsstrahlung from89Sr is measured by a coincidence arrangement, where the photons are detected in a NaI(Tl) scintillation crystal and the corresponding β-rays by two plastic scintillators, defining two angles of emission, 45° and 70°, between the β-particles and the internal bremsstrahlung. It was possible to test the differential probability for the internal bremsstrahlung emission as given by the theory of Knipp and Uhlenbeck. The result fits fairly well the theoretical expectations.