Updated neutron-multiplicity sorting method for producing photoneutron average energies and resolving multiple firing events

Abstract Photoneutron measurements in the Giant Dipole Resonance region have been recently performed using quasimonochromatic Laser Compton Scattering γ -ray beams at NewSUBARU (Japan) for 59Co, 89Y, 103Rh, 139La, 159Tb, 165Ho, 169Tm, 181Ta, 197Au and 209Bi. Experimental ( γ , x n ) with x  = 1 – 4 photoneutron cross sections have been obtained with a direct neutron-multiplicity sorting method associated to a flat-efficiency neutron detector , which operates under single firing conditions obtained by low reaction rates. In this paper, we discuss recent developments to the neutron-multiplicity sorting procedure dedicated to (i) resolving multiple firing events and to (ii) extracting the average energies of ( γ , x n ) photoneutrons. The method is tested on 159Tb experimental data.