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Title: Forward ion acceleration by laser-driven collisionless filamentary shocks in underdense plasmas
Abstract We have experimentally investigated the collisionless shock acceleration of ions via the interaction of a relativistic intensity (3 × 1019W/cm2), 1.053 µm wavelength laser pulse with an underdense plasma. This plasma is formed through the use of a novel cluster jet design that allows for control of the plasma peak density and front scale length without the use of additional plasma-forming laser pulses. When the front density scale length of the target plasma is less than 60 µm, the laser pulse (1 J, 400 fs) is capable of launching an electrostatic shock wave that accelerates a proton beam. This beam is shown to have a narrow divergence angle of 0.8°, a peak flux of 14 × 106protons/sr with an ion energy exceeding 440 keV. Particle-in-cell simulations indicate this narrow ion beam is produced by converging shocks generated via filamentation of the laser pulse in high-density (near critical) plasma.  more » « less
Award ID(s):
2126181
PAR ID:
10704431
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Cambridge University Press
Date Published:
Journal Name:
Laser and Particle Beams
Volume:
42
ISSN:
0263-0346
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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