Calculated ratio of preheat energy to total hard-x-ray energy for CH shells. The curves marked “transport” are the result of multigroup fast-electron transport through the thick shell for an initially Maxwellian distribution of temperature . The solid curve refers to cold-matter calculation, and the dashed curve to plasma calculation. The curve marked ratio is the ratio of the energy-loss rates for slowing-down collisions (in cold matter) and for bremsstrahlung emission for electrons of a single energy . The abscissa values for the two curves refer to fast-electron temperature (for the transport curve) and to fast-electron energy (for the -ratio curve).
Measured line of molybdenum from the irradiation of a CH-coated molybdenum sphere, using the laser conditions discussed in the text. The calibrated line was used to cross calibrate the hard-x-ray detectors.
Calculations for a molybdenum target. (a) Ratio of preheat energy and emission energy in the Mo line, calculated by a multigroup electron transport through a molybdenum sphere. The curve marked “with opacity” includes the transport of the line through the target. (b) The curves marked transport and ratio are equivalent to the corresponding curves in Fig. 1. The dotted curve is the inverse of the empirical x-ray efficiency of an x-ray tube with a Mo anode (the abscissa for the latter curve is given by the tube voltage).
Preheat energy as a fraction of the incident laser energy deduced from the hard-x-ray measurements. Open circles, deuterium-gas-filled thick CH shells; point marked Mo, CH-coated molybdenum sphere; solid squares, cryogenic-deuterium-filled CH shells. For the point at the end of the arrow see the text.
Calculated ratio of preheat energy and total hard-x-ray energy in the cryogenic-deuterium fuel. The electron transport code used the electron-density profiles calculated by LILAC. Shown is the ratio at two instances during the laser pulse.
Article metrics loading...
Full text loading...