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arXiv · 2105.11094

Numerical investigation of spallation neutrons generated from petawatt-scale laser-driven proton beams

B. Martinez·S. N. Chen·S. Bolaños·N. Blanchot·G. Boutoux·W. Cayzac·C. Courtois·X. Davoine·A. Duval·V. Horny·I. Lantuejoul·L. Le Deroff·P. E. Masson-Laborde·G. Sary·B. Vauzour·R. Smets·L. Gremillet·J. Fuchs
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Abstract

Due to their high cost of acquisition and operation, there are still a limited number of high-yield, high-flux neutron source facilities worldwide. In this context, laser-driven neutron sources offer a promising, cheaper alternative to those based on large-scale accelerators, with, in addition, the potential of generating compact neutron beams of high brightness and ultra-short duration. In particular, the predicted capability of next-generation petawatt (PW)-class lasers to accelerate protons beyond the 100 MeV range should unlock efficient neutron generation through spallation reactions. In this paper, this scenario is investigated numerically through particle-in-cell and Monte Carlo simulations, modeling, respectively, the laser acceleration of protons from thin-foil targets and their subsequent conversion into neutrons in secondary heavy-ion targets. Laser parameters relevant to the 1 PW LMJ-PETAL and 1-10 PW Apollon systems are considered. Under such conditions, neutron fluxes exceeding $10^{23}\,\rm n\,cm^{-2}\,s^{-1}$ are predicted, opening up attractive fundamental and applicative prospects.

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B. Martinez, S. N. Chen, S. Bolaños, N. Blanchot, G. Boutoux, W. Cayzac, C. Courtois, X. Davoine, A. Duval, V. Horny, I. Lantuejoul, L. Le Deroff, P. E. Masson-Laborde, G. Sary, B. Vauzour, R. Smets, L. Gremillet, J. Fuchs. 2021-06-22. Numerical investigation of spallation neutrons generated from petawatt-scale laser-driven proton beams. https://doi.org/10.1063/5.0060582

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