AUTHOR=Jiao X. , Curry C. B. , Gauthier M. , Chou H.-G. J. , Fiuza F. , Kim J. B. , Phan D. D. , McCary E. , Galtier E. C. , Dyer G. M. , Ofori-Okai B. K. , Labun L. , Labun O. Z. , Schoenwaelder C. , Roycroft R. , Tiwari G. , Glenn G. D. , Treffert F. , Glenzer S. H. , Hegelich B. M. 

TITLE=High deuteron and neutron yields from the interaction of a petawatt laser with a cryogenic deuterium jet

JOURNAL=Frontiers in Physics

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2022.964696

DOI=10.3389/fphy.2022.964696

ISSN=2296-424X

ABSTRACT=<p>A compact high-flux, short-pulse neutron source would have applications from nuclear astrophysics to cancer therapy. Laser-driven neutron sources can achieve fluxes much higher than spallation and reactor neutron sources by reducing the volume and time in which the neutron-producing reactions occur by orders of magnitude. We report progress towards an efficient laser-driven neutron source in experiments with a cryogenic deuterium jet on the Texas Petawatt laser. Neutrons were produced both by laser-accelerated multi-MeV deuterons colliding with Be and mixed metallic catchers and by <italic>d</italic> (<italic>d</italic>,<italic>n</italic>)<sup>3</sup>He fusion reactions within the jet. We observed deuteron yields of 10<sup>13</sup>/shot in quasi-Maxwellian distributions carrying <inline-formula id="inf1"><mml:math id="m1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>∼</mml:mo><mml:mn>8</mml:mn><mml:mo>−</mml:mo><mml:mn>10</mml:mn><mml:mi>%</mml:mi></mml:math></inline-formula> of the input laser energy. We obtained neutron yields greater than 10<sup>10</sup>/shot and found indications of a deuteron-deuteron fusion neutron source with high peak flux (<inline-formula id="inf2"><mml:math id="m2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>&gt;</mml:mo><mml:mn>1</mml:mn><mml:msup><mml:mrow><mml:mn>0</mml:mn></mml:mrow><mml:mrow><mml:mn>22</mml:mn></mml:mrow></mml:msup></mml:math></inline-formula> cm<sup>−2</sup> s<sup>−1</sup>). The estimated fusion neutron yield in our experiment is one order of magnitude higher than any previous laser-induced <italic>dd</italic> fusion reaction. Though many technical challenges will have to be overcome to convert this proof-of-principle experiment into a consistent ultra-high flux neutron source, the neutron fluxes achieved here suggest laser-driven neutron sources can support laboratory study of the rapid neutron-capture process, which is otherwise thought to occur only in astrophysical sites such as core-collapse supernova, and binary neutron star mergers.</p>