An analytical model for the study of the conditions for central ignition of imploding shell targets is presented. The model is based on a description of the stagnation phase in which the shell is considered to stagnate isentropically except in a central region of the fuel where the ignition profiles are determined by the competition of the energy losses due to thermal conduction and radiation with the heating due to compressional work and alpha particle deposition of energy. As a result, the temperature and the confinement parameter of the central spark are found to be dependent on the implosion velocity v0, and the ignition conditions are obtained consistently with the implosion dynamics. In addition, the minimum energy of the beam EBignrequired for ignition is calculated and the scaling EBign∝ v0-5is found, which is in good agreement with previously reported simulations.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Condensed Matter Physics