Analysis of limited coverage effects on areal density measurements in inertial confinement fusion implosions

Abstract

Accurate diagnosis of areal density (ρR) is critical for the inference of performance metrics in inertial confinement fusion implosions. One potential source of error in this diagnosis is the existence of low mode perturbations in the imploding target, which lead to asymmetries in the inference of the ρR from different lines of sight. Here, the error accrued as a result of limited coverage of the sphere due to a finite number of detectors is quantified, and the development of a forward scatter measurement from the OMEGA neutron time-of-flight detectors is motivated. A method by which the 1D-equivalent 4π-averaged ⟨ ρ R ⟩ can be reconstructed, if accurate mode information can be diagnosed by other means, is validated.