Neutron production in cavity pressure acceleration of plasma objects

T Chodukowski,M Pfeifer,M Krupka,K Jach,J Cikhardt,S Borodziuk,T Burian,T Pisarczyk,Z Rusiniak,R Świerczyński ,R Dudžák ,D Terwińska ,P Tchórz ,J Skàla ,J Krása ,M Szymański ,J Dostál ,Sushil Singh ,M Rosiński ,M Krůs

doi:10.1063/5.0005977

Abstract

The laser-induced Cavity Pressure Acceleration (CPA) scheme [S. Borodziuk et al., Appl. Phys. Lett. 95, 231501 (2009)] allows for effective transformation of the laser energy into the kinetic energy of plasma streams and dense plasma objects. It has been proven that using long-wavelength laser beams, with relatively low energies (up to 500 J for λ1 = 1.315 µm and FWHM = 350 ps), it is possible to accelerate macroparticles to very high velocities (above 107 cm/s). The study of neutron yield showed the benefit of CPA in delivering ion temperatures and density sufficient to reach the thermonuclear region.

Highlights

Fast ignition,2,3 one of the inertial confinement fusion (ICF) concepts, requires less energy when compared to the classical, spherical compression scheme
Recent studies at the PALS (Prague Asterix Laser System) using an iodine laser showed the efficiency of the cavity pressure acceleration (CPA) method in producing very highenergy macroparticles
Cavity Pressure Acceleration (CPA) eliminates the basic contradiction of the classic ablative acceleration process in which the way of getting high macroparticle velocity simultaneously leads to mass loosing

Summary

INTRODUCTION

One of the inertial confinement fusion (ICF) concepts, requires less energy when compared to the classical, spherical compression scheme. It consists of the compression of thermonuclear fuel, apart from dense core heating. A driver capable of delivering an intense energy pulse to a properly constructed thermonuclear target needs to be found. This can be done with high-enough pressures of the plasma produced in “cavity”-type targets. Recent studies at the PALS (Prague Asterix Laser System) using an iodine laser showed the efficiency of the cavity pressure acceleration (CPA) method in producing very highenergy macroparticles.. In the recent experiment, carried out at the PALS, specific targets were tested (Fig. 1), using a variant of CPA: the so-called “backward acceleration scheme” or “Reversed Acceleration Scheme” (RAS).

EXPERIMENTAL SETUP AND RESULTS

NUMERICAL SIMULATIONS

CONCLUSIONS