Jitter characterization and flux scaling of a novel mass-limited liquid target for ultrashort laser-driven fast neutrons

Recent advances in high-power laser engineering and non-linear ultrafast pulse compression will soon yield functional relativistic laser drivers with terawatt (TW) peak powers and kilowatt average powers. Logarithmic increases to driver repetition rates demand a paradigm shift in the way experimenters must approach shot-to-shot targetry at kHz/MHz repetition rates and have set the stage for the preeminence of tabletop laser-driven fusion neutron sources with high-brightness. We report on initial mass-limited target spatial-temporal jitter for micron-scale deuterated liquid targets electrohydrodynamically dispensed at multi-kHz repetition rates. Spatial expansion dynamics of critical-density fusion plasma plumes resulting from irradiation of these targets by sub-relativistic and relativistic Ti:Sapphire laser pulses is time-resolved via an off-harmonic back-lighter generated via optical parametric amplification. Isotropic fast neutron yield scaling trends for this mass-limited target are presented for various pre-pulse temporal delay parameters (ps-to-ns) and driver pulse durations spanning from 38-350 femtoseconds. Data from long-pulse (150-350 fs) interactions is extrapolated in terms of expected neutron flux performance realized from TW-class ultrashort Yb-doped fiber laser systems leveraging coherent spatial and spectral beam combining techniques.