Resonance capture γ-ray spectrometry at Lead Slowing-down Neutron Spectrometer

A new method of measurement of the γ-ray spectra from resonance neutron capture that can be realized at Lead Slowing-down Neutron Spectrometers was proposed and tested experimentally. The specific feature of the method is the shielding of germanium detector by a “thick” investigated sample that absorbs intensive neutron flux with energies corresponding to sample resonances. In these energy regions the detector response on neutron irradiation is considerably reduced while the sample γ-ray spectra are greatly strengthened. The detector response γ-ray spectra are presented and analysed, and the spectra from neutron capture in tantalum resonances at energies 4.28 and 10.36 eV are shown. The obtained results demonstrate the usefulness of the proposed method. ew excited levels in germanium isotopes are proposed.