3.9 Calibrations of 14 MeV Neutron Generators
95
materials of choice for ecient proton to neutron conversion for laser systems
in the near-term future, when much higher proton energies will be available. e
future laser systems might reach laser intensities well beyond 10
21
W/cm
2
/μm
2
,
even up to 10
24
W/cm
2
/μm
2
, in the next decade. At these intensities proton ener-
gies will be high enough to initiate spallation reactions in high Z solid targets.
Spallation reactions are even more ecient in neutron production than ssion
reactions, making for higher eciency neutron generation. e characteristics
of these neutron sources are an anisotropic neutron ux, a continuous energy
spectrum, and an extremely short pulse width.
By using a combination of ...