Direct observation of particles with energy >10 MeV/u from laser-induced fusion in ultra-dense deuterium

Research paper by Leif Holmlid

Indexed on: 12 Feb '13Published on: 12 Feb '13Published in: Physics - Instrumentation and Detectors


Nuclear fusion in ultra-dense deuterium D(-1) induced by 0.2 J pulses with 5 ns pulse length ejects ions with energies in the MeV range. The ns-resolved signal to a collector can be observed directly on an oscilloscope, showing ions arriving with energies in the range 2-14 MeV u-1 at flight times 12-100 ns, mainly protons from the fusion process and deuterons ejected by proton collisions. Electrons and photons give almost no contribution to the fast signal. The observed signal at several mA peak current corresponds to 1x10^13 particles released per laser shot and to an energy release > 1 J assuming isotropic formation and average particle energy of 3 MeV as observed. A movable slit close to the laser target gives spatial resolution of the signal generation, showing almost only fast ions from the point of laser impact and penetrating photons from the plasma outside the laser impact point. The initial photon pulse from the fusion process is observed by a photomultiplier detector on-line.