Laser Driven Neutron Generation at the Texas Petawatt

Ultrashort Pulsed Neutron Source

“…Two experiments in the past year [4,10,11] reported lasergenerated neutron yields as high as 10 10 n/sr per laser shot. Their scheme is based on high-energy hydrogen ions emitted from laser-irradiated targets.…”

“…These ions impinged on the Cu and were stopped in the front plate [17,25], as shown in the resulting activation signal. The ion energy distribution was measured using magnetic spectrometers (see supplementary note [21] for details) and found to reach 25 MeV for protons [26,27]. Half-life measurement of the activation signal for these plates verified that the resulting nuclei ( 63 Zn, τ 1/2 = 38 min) were indeed the product of protons interacting with 63 Cu nuclei.…”

“…In addition, we directly measured neutrons using eight BTI Bubble dosimeters [27,33] positioned outside the experimental chamber at a distance of 80 cm from the interaction point. These were arranged at positions 0º, 30º, 45º, 60º, 90º, 135º, 180º and 335º with respect to the incoming laser direction.…”