Photoneutron measurements in the GDR region at ELI-NP

The Extreme Light Infrastructure - Nuclear Physics (ELI-NP) is a facility dedicated to nuclear physics research with extreme electromagnetic fields. The expected gamma-ray beams with energies up to 20 MeV, 0.5% relative energy resolution and similar to 10(8) photons per second intensity will allow precise photonuclear measurements. Nuclear structure experiments will involve photo-excitations of mainly low-spin collective states and the observation of the radiation emitted in the subsequent decays. Photoneutron reactions and elastic and inelastic photon scattering are proposed to be recorded using a mixed gamma-neutron detection system using LaBr3:Ce, CeBr3, BC501A and GS20 detectors. Photoneutron (gamma, xn) with x= 1,2 reactions cross sections measurements will be performed with a 4 pi flat efficiency neutron detection system dedicated for neutron multiplicity sorting experiments. The detection system is comprised of He-3 counters embedded in a moderator block. The paper will introduce the experimental setups dedicated to studies of the nuclear Giant Dipole Resonance excitation mode using the high energy resolution and high intensity ELI-NP gamma-ray beams. The feasibility studies performed using extensive Geant4 simulations, results of detector tests will be presented.