Speaker
Description
The nuclear resonance fluorescence (NRF) method was used to study the electromagnetic dipole response of $^{242}$Pu at the superconducting Darmstadt linear electron accelerator S-DALINAC. Monoenergetic electrons with an energy of 3.7 MeV were used to produce bremsstrahlung to irradiate the PuO$_2$ sample with a total mass of about 1 g. The target was highly enriched in the isotope $^{242}$Pu and kept in a special target container due to its total radioactivity of about 370 MBq. Resonantly scattered photons were detected with two high-purity Germanium detectors placed at angles of 90° and 130° relative to the direction of the incident photon beam. NRF spectra of an empty target container, gamma-ray spectra of the sample’s radioactivity and background measurements were taken into account to identify NRF signals of the sample. Gamma rays from the decays of photo-excited states of $^{242}$Pu were observed - making $^{242}$Pu the heaviest nuclide for which NRF information on excited states is available for the moment. Details of the experiment will be described, γ-ray spectra presented and preliminary results discussed.
We thank the Institute of Resource Ecology of HZDR for providing the $^{242}$Pu-sample. This work has been supported by the State of Hesse under the grant ’Nuclear Photonics’ within the LOEWE program.
