Target gain and sensitivity to low-mode asymmetry at NIF*

The NIF implosion experiment N221204 produced more than 3 MJ of fusion yield and surpassed unity target gain for the first time. The predecessor experiment, N220919, and a subsequent experiment, N230618, had significant low-mode asymmetries (2 and 1 respectively) relative to N221204. While this design has sufficient ignition margin that the degraded experiments still surpassed Lawson's criterion for ignition and produced yields exceeding one MJ, both were degraded by a factor of ~2 in yield and therefore had target gains below unity. The data therefore provide a unique dataset on our sensitivity to low-mode asymmetry in the regime of ignition and burn propagation.