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arXiv · 2311.12653

A Comprehensive Characterization of the Neutron Fields Produced by the Apollon Petawatt Laser

Ronan Lelièvre·Weipeng Yao·Tessa Waltenspiel·Itamar Cohen·Arie Beck·Erez Cohen·David Michaeli·Ishay Pomerantz·Donald Cort Gautier·François Trompier·Quentin Ducasse·Pavlos Koseoglou·Pär-Anders Söderström·François Mathieu·Amokrane Allaoua·Julien Fuchs
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Abstract

Since two decades, laser-driven neutron emissions are studied as they represent a complementary source to conventional neutron sources, with further more different characteristics (i.e. shorter bunch duration and higher number of neutrons per bunch). We report here a global, thorough characterization of the neutron fields produced at the Apollon laser facility using the secondary laser beam (F2). A Double Plasma Mirror (DPM) was used to improve the temporal contrast of the laser which delivers pulses of 24 fs duration, a mean on-target energy of ~10 J and up to 1 shot/min. The interaction of the laser with thin targets (few tens or hundreds of nm) in ultra-high conditions produced enhanced proton beams (up to 35 MeV), which were then used to generate neutrons via the pitcher-catcher technique. The characterization of these neutron emissions is presented, with results obtained from both simulations and measurements using several diagnostics (activation samples, bubble detectors and Time-of-Flight detectors), leading to a neutron yield of ~$4.10^{7}$ neutrons/shot. Similar neutron emissions were observed during shots with and without DPM, while fewer X-rays are produced when the DPM is used, making this tool interesting to adjust the neutrons/X-rays ratio for some applications like combined neutron/X-ray radiography.

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Ronan Lelièvre, Weipeng Yao, Tessa Waltenspiel, Itamar Cohen, Arie Beck, Erez Cohen, David Michaeli, Ishay Pomerantz, Donald Cort Gautier, François Trompier, Quentin Ducasse, Pavlos Koseoglou, Pär-Anders Söderström, François Mathieu, Amokrane Allaoua, Julien Fuchs. 2023-11-21. A Comprehensive Characterization of the Neutron Fields Produced by the Apollon Petawatt Laser. https://arxiv.org/abs/2311.12653

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