Inline Study of Low-Mode Asymmetry Induced by Polarized Cross-Beam Energy Transfer Interaction in Laser-Direct-Drive Spherical Implosions on OMEGA*

Laser-direct-drive shell implosion experiments conducted on the OMEGA laser have been found to be prone to systematic flow anomalies at stagnation, which persist after elimination of perturbation sources such as target offset, vibration, stalk and ice non-uniformity. Recently, a proposed explanation for this anomaly has been the polarized Cross Beam Energy Transfer (CBET) interaction in the OMEGA beam configuration. Here we present the first polarized CBET model fully coupled to a radiative hydrodynamics code, implemented in the ASTER/IFRIIT 3D ICF code (LLE/CELIA). The inline model is used to investigate the polarized CBET interaction in two cryogenic experiments conducted at OMEGA: first in the case of a strong low mode induced by illumination imbalance, and a second which was in an optimal implosion configuration. We present simulation results with varying CBET and illumination configurations and compared to velocity and direction measurements of the DT flow obtained from neutron diagnostics. An excellent agreement with the data is found in the case that is dominated by balance and pointing error, while simulations in the second case will be finalized in the coming weeks. These results shine light on the definitive effect of polarized CBET in OMEGA implosions.