Speaker: Andrew Lanzrath (MIT)
Title: Probing light-ion nuclear reactions relevant to astrophysics in high-energy-density plasmas
Abstract: High-quality nuclear data is needed to inform models of big bang and stellar nucleosynthesis. Historically, nuclear reactions have been studied at accelerator facilities where an ion beam impinges upon a cold target. However, in astrophysical environments, these reactions take place in high-energy-density (HED) plasmas. Beam-target fusion reactions in a cold target with bound electrons are not physically comparable to the thermal distributions of reacting ions and free electrons in HED plasmas, which motivated the development of a platform to study nuclear reactions at laser-driven inertial confinement fusion facilities. HED plasmas provide a different set of challenges for studying nuclear reactions since implosion conditions may affect the fusion product measurements, and the low cross-sections at astrophysically-relevant temperatures require improved diagnostics to measure low nuclear yields. This presentation will provide an overview of the ongoing efforts to probe light-ion reactions in experiments at the National Ignition Facility (NIF) and OMEGA laser facility specifically for the six-nucleon reactions T+3He and 3He+3He as well as the D+3He proton-gamma branching ratio, which has been identified as potential diagnostic for measuring electron plasma screening in upcoming experiments at the NIF.