Electron energy distributions through superdense matter by Monte-Carlo simulations

¹ Graduate School of Engineering, Osaka University, 2-1, Yamada-oka, Suita, Osaka 565-0871, Japan
² Institute of Laser Engineering, Osaka University, 2-6, Yamada-oka, Suita, Osaka 565-0871, Japan

^a e-mail: okabayashi-a@eie.eng.osaka-u.ac.jp

Published online: 15 November 2013

Abstract

We have studied energy distribution of fast electrons passing through a highly compressed core plasma for fast ignition research in inertial confinement fusion. Recent PIC calculations indicate that the collective effect of electric and magnetic fields on the transport may be less significant than the binary collisions in the case of a high density fusion pellet. In order to understand the net effect of binary collisions in dense plasma, we calculate electron energy distributions at several viewing angles using an electromagnetic cascade Monte-Carlo simulation, EGS5, for estimation of the contribution of multi collisional process. Here, the construction of physical parameters in the code were taken from the calculation results given by 2 dimensional particle-in-cell simulations. In the result, the number of electrons detected on the laser axis within the range to 15 MeV significantly decreases for the superdense region (max: 1.6⋅10²⁵[/cm³]) compared with the low density plasma. The reduction on the electron number decreases with increase of observation angles gradually and finally the number almost coincides more than 40 degrees.