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arXiv · 0903.3718

Hole boring in a DT pellet and fast ion ignition with ultra-intense laser pulses

N. Naumova·T. Schlegel·V. T. Tikhonchuk·C. Labaune·I. V. Sokolov·G. Mourou
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Abstract

Recently achieved high intensities of short laser pulses open new prospects in their application to hole boring in inhomogeneous overdense plasmas and for ignition in precompressed DT fusion targets. A simple analytical model and numerical simulations demonstrate that pulses with intensities exceeding 1022 W/cm2 may penetrate deeply into the plasma as a result of efficient ponderomotive acceleration of ions in the forward direction. The penetration depth as big as hundreds of microns depends on the laser fluence, which has to exceed a few tens of GJ/cm2. The fast ions, accelerated at the bottom of the channel with an efficiency of more than 20%, show a high directionality and may heat the precompressed target core to fusion conditions.

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N. Naumova, T. Schlegel, V. T. Tikhonchuk, C. Labaune, I. V. Sokolov, G. Mourou. 2009-03-22. Hole boring in a DT pellet and fast ion ignition with ultra-intense laser pulses. https://doi.org/10.1103/physrevlett.102.025002

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