Scalings of implosion experiment for high neutron yield

A series of experiments focused on high neutron yield has been done with Gekko-XII green laser system. DT neutron yield of 1013, pellet gain 0.2 %, and coupling efficiency 5.5 % have been achieved. Based on the experimental data for more than 70 shots, the scaling laws of the neutron yield and the related physical quantities have been studied. The comparison of the experimental neutron yield with that obtained by one-dimensional fluid code has led us to a conclusion that most of the neutron yield produced in the stagnation phase is not observed in the experiment because of fuel-pusher mixing possibly induced by the Rayleigh-Taylor instability. A DT core gain of 5 % has also been obtained. The experimental data plotted in the ρR-Ti diagram indicate that for igniting the fuel, the ion temperature is sufficiently high, while the ρR is less by two orders of magnitude than the required value. (author)