159 research outputs found
A tunable radiation source by coupling laser-plasma-generated electrons to a periodic structure
Near-infrared radiation around 1000 nm generated from the interaction of a high-density MeV electron beam, obtained by impinging an intense ultrashort laser pulse on a solid target, with a metal grating is observed experimentally. Theoretical modeling and particle-in-cell simulation suggest that the radiation is caused by the Smith-Purcell mechanism. The results here indicate that tunable terahertz radiation with tens GV=m field strength can be achieved by using appropriate grating parameter
Correlation between laser accelerated MeV proton and electron beams using simple fluid model for target normal sheath acceleration
Copyright 2010 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 17(7), 073110, 2010 and may be found at http://dx.doi.org/10.1063/1.345906
Anomalous Self-Generated Electrostatic Fields in Nanosecond Laser-Plasma Interaction
Electrostatic (E) fields associated with the interaction of a
well-controlled, high-power, nanosecond laser pulse with an underdense plasma
are diagnosed by proton radiography. Using a current 3D wave propagation code
equipped with nonlinear and nonlocal hydrodynamics, we can model the measured
E-fields that are driven by the laser ponderomotive force in the region where
the laser undergoes filamentation. However, strong fields of up to 110 MV/m
measured in the first millimeter of propagation cannot be reproduced in the
simulations. This could point to the presence of unexpected strong thermal
electron pressure gradients possibly linked to ion acoustic turbulence, thus
emphasizing the need for the development of full kinetic collisional
simulations in order to properly model laser-plasma interaction in these
strongly nonlinear conditions.Comment: 12 pages, 4 figures, submitted to Physics of Plasma
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