An experiment was performed on the OMEGA EP Laser System to investigate the effects of magnetic fields on laser imprint. A 30 $\mu \mathrm{m}$ thick CH target was driven by a single beam delivering 3.0 kJ of UV energy in a 5 ns square pulse without smoothing by spectral dispersion. The Rayleigh-Taylor amplification of this beam's imprint on the target surface was monitored using face-on gated x-ray radiography from a Gd backlighter. Magnetic fields of up to $45\mathrm{T}$ were applied normal to the target surface. Analysis of the resulting radiographs shows a $60\pm 13\%$ increase in the spectrally resolved surface perturbation amplitudes, consistent at all times and for all unsaturated frequencies. This consistency indicates that the increase in perturbation amplitudes was due to a change in the initial amplitudes rather than Rayleigh-Taylor growth. This is supported by the trajectory of individual modes and the inferred time-averaged perturbation growth rates. Laser imprint is therefore inferred to have increased due to strong magnetic fields that remain in the conduction zone of the target, suppressing off-axis electron motion and limiting the effects of thermal smoothing.

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• Direct drive
• Hydrodynamic instabilities
• Inertial confinement fusion
• Laser-plasma interactions
• Magnetohydrodynamics
• Magnetoinertial fusion
• Plasma-beam interactions
• Rayleigh-Taylor instability
• Hydrodynamics
• Magnetohydrodynamic techniques
• X-ray & gamma ray plasma measurements
• X-ray imaging