Spiraling Beam Illumination Uniformity on Heavy Ion Fusion Target

TL;DR

This paper demonstrates that spiraling beam axis motion in heavy ion inertial confinement fusion can achieve a few percent uniformity in target illumination by leveraging oscillating energy deposition to reduce nonuniformities.

Contribution

It introduces a novel spiraling beam axis motion technique to improve uniformity in heavy ion fusion target illumination, addressing initial imprint issues.

Findings

Achieved a few percent nonuniformity in beam illumination.

Oscillating energy deposition reduces initial imprint effects.

Simulation confirms uniformity oscillates with beam wobbling frequency.

Abstract

A few percent wobbling-beam illumination nonuniformity is realized in heavy ion inertial confinement fusion (HIF) by a spiraling beam axis motion in the paper. So far the wobbling heavy ion beam (HIB) illumination was proposed to realize a uniform implosion in HIF. However, the initial imprint of the wobbling HIBs was a serious problem and introduces a large unacceptable energy deposition nonuniformity. In the wobbling HIBs illumination, the illumination nonuniformity oscillates in time and space. The oscillating-HIB energy deposition may contribute to the reduction of the HIBs illumination nonuniformity. The wobbling HIBs can be generated in HIB accelerators and the oscillating frequency may be several 100MHz-1GHz. Three-dimensional HIBs illumination computations presented here show that the few percent wobbling HIBs illumination nonuniformity oscillates successfully with the same wobbling HIBs frequency.