MEASUREMENTS AND SIMULATIONS OF LOW-ENERGY, THICK TARGET BREMSSTRAHLUNG SPECTRA

Nuclear resonance fluorescence (NRF) experiments on the isotopes C-13, Na-23, Al-27, P-31, Cl-35, and Ti-48 with transitions of known strengths have been performed to determine the relative spectral shape of low energy, thick target bremsstrahlung spectra. The experimental results (endpoint energy E0 = 4.1 MeV) are compared with Monte Carlo simulations. It is concluded that a linear function represents a rather precise approximation of the shape of this bremsstrahlung spectrum near the endpoint energy. Therefore, a linear interpolation of the photon flux between well known data points enables a fast and sufficiently precise analysis of NRF experiments using photon sources of this kind.