A fission-fragment-sensitive target for X-ray spectroscopy in neutron-induced fission

A fission-fragment-sensitive detector built for low-energy photon spectroscopy applications at the WNR “white” neutron source at Los Alamos is described. The detector consists of eight layers of thin photovoltaic cells, onto which <f>1 mg/cm2</f> of pure <f>238U</f> is deposited. The detector serves as an active target to select fission events from background and other reaction channels. The fairly small thickness of the detector with respect to transmission of 20–<f>50 keV</f> photons permits the measurement of prompt fission-fragment X-rays. Results with the GEANIE photon spectrometer are presented. [Copyright &y& Elsevier]