The impact Of impurity ion in deuterium-tritium fuel on the energy deposition pattern Of The Proton Ignitor Beam

Abstract

The ignition stage of deuterium-tritium fuel in inertial confinement fusion is a challenging task affected by many undesirable processes especially material mixing processes in the hot-spot region. In this research, an alternative proposal of the enhanced energy deposition in the proton fast ignition has been suggested. It consists of two primary assumptions of the beam-plasma system. In the first place, we have adopted the proton beam generated by TNSA or RPA mechanisms, each described by a Maxwellian or Gaussian energy distributions. Next, a realistic, non-uniform fuel plasma was adopted. Then, the cumulative stopping power of a proton beam of 10 kJ energy, penetrating the low content metal-contaminated deuterium-tritium fuel has been examined. It has been shown that in the case of the very low impurity fractions, irregular spatial fluctuations in the cumulative stopping power relative to pure fuel plasma emerges. However, at the higher concentrations, a systematic pattern becomes visible such that the contribution of the deep layers in the stopping power reduces. We observe the enhanced energy deposition close to the corona/dense core interface. It has been shown that the corona/dense core energy deposition ratio differs by up to 2.5% between pure and contaminated DT plasma. In the contaminated fuel plasma, energy deposition in the TNSA regime will effectively heat the plasma corona. While in the RPA counterpart, at a similar level of contamination, most of the incident beam energy remains inside the core fuel region.