The intense ultrashort laser interacting with the thermonuclear fuel may produce a relativistic plasma and MeV electron beam, how to fix the Lorentz factors of the particles in the plasma and model the energy deposition of MeV electron beams are important subjects. In this letter, we demonstrate the exact relation between the average Lorentz factor and the temperature of the system; and then obtained the relativistic modified formula for the energy loss of the relativistic electron-beam due to binary electron-electron collisions. Another important energy loss mechanism, the excitation of Langmuir collective plasma oscillation, is also treated within the relativistic framework. Hence, we re-examine theoretically the possibility of igniting hot spots in the super-compressed DT target and the answer is that the fast ignitor scenario is able to yield thermonuclear ignition in the target.
Theoretical study on the energy loss induced by electron collisions in weakly ionized air plasma
