skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A detailed examination of laser-ion acceleration mechanisms in the relativistic transparency regime using tracers

Abstract

Here we present a particle-in-cell study of linearly polarized laser-ion acceleration systems, in which we use both two-dimensional (2D) and three-dimensional (3D) simulations to characterize the ion acceleration mechanisms in targets which become transparent to the laser pulse during irradiation. First, we perform a target length scan to optimize the peak ion energies in both 2D and 3D, and the predictive capabilities of 2D simulations are discussed. Tracer analysis allows us to isolate the acceleration into stages of target normal sheath acceleration (TNSA), hole boring (HB), and break-out afterburner (BOA) acceleration, which vary in effectiveness based on the simulation parameters. The thinnest targets reveal that enhanced TNSA is responsible for accelerating the most energetic ions, whereas the thickest targets have ions undergoing successive phases of HB and TNSA (in 2D) or BOA and TNSA (in 3D); HB is not observed to be a dominant acceleration mechanism in the 3D simulations. It is in the intermediate optimal regime, both when the laser breaks through the target with appreciable amplitude and when there is enough plasma to form a sustained high density flow, that BOA is most effective and is responsible for the most energetic ions. Eliminating the transverse laser spot sizemore » effects by performing a plane wave simulation, we can isolate with greater confidence the underlying physics behind the ion dynamics we observe. Specifically, supplemented by wavelet and FFT analyses, we match the post-transparency BOA acceleration with a wave-particle resonance with a high-amplitude low-frequency electrostatic wave of increasing phase velocity, consistent with that predicted by the Buneman instability.« less

Authors:
ORCiD logo [1];  [1];  [1];  [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE; LANL Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
1482934
Alternate Identifier(s):
OSTI ID: 1434053
Report Number(s):
LA-UR-18-21781
Journal ID: ISSN 1070-664X
Grant/Contract Number:  
89233218CNA000001
Resource Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 25; Journal Issue: 4; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; plasma flows; wave mechanics; ion accelerator; plasma waves; velocity gradient tensor; particle-in-cell method; laser plasma interactions; electrostatics; plasma instabilities

Citation Formats

Stark, David J., Yin, Lin, Albright, Brian J., Nystrom, William, and Bird, Robert. A detailed examination of laser-ion acceleration mechanisms in the relativistic transparency regime using tracers. United States: N. p., 2018. Web. doi:10.1063/1.5028129.
Stark, David J., Yin, Lin, Albright, Brian J., Nystrom, William, & Bird, Robert. A detailed examination of laser-ion acceleration mechanisms in the relativistic transparency regime using tracers. United States. doi:10.1063/1.5028129.
Stark, David J., Yin, Lin, Albright, Brian J., Nystrom, William, and Bird, Robert. Thu . "A detailed examination of laser-ion acceleration mechanisms in the relativistic transparency regime using tracers". United States. doi:10.1063/1.5028129. https://www.osti.gov/servlets/purl/1482934.
@article{osti_1482934,
title = {A detailed examination of laser-ion acceleration mechanisms in the relativistic transparency regime using tracers},
author = {Stark, David J. and Yin, Lin and Albright, Brian J. and Nystrom, William and Bird, Robert},
abstractNote = {Here we present a particle-in-cell study of linearly polarized laser-ion acceleration systems, in which we use both two-dimensional (2D) and three-dimensional (3D) simulations to characterize the ion acceleration mechanisms in targets which become transparent to the laser pulse during irradiation. First, we perform a target length scan to optimize the peak ion energies in both 2D and 3D, and the predictive capabilities of 2D simulations are discussed. Tracer analysis allows us to isolate the acceleration into stages of target normal sheath acceleration (TNSA), hole boring (HB), and break-out afterburner (BOA) acceleration, which vary in effectiveness based on the simulation parameters. The thinnest targets reveal that enhanced TNSA is responsible for accelerating the most energetic ions, whereas the thickest targets have ions undergoing successive phases of HB and TNSA (in 2D) or BOA and TNSA (in 3D); HB is not observed to be a dominant acceleration mechanism in the 3D simulations. It is in the intermediate optimal regime, both when the laser breaks through the target with appreciable amplitude and when there is enough plasma to form a sustained high density flow, that BOA is most effective and is responsible for the most energetic ions. Eliminating the transverse laser spot size effects by performing a plane wave simulation, we can isolate with greater confidence the underlying physics behind the ion dynamics we observe. Specifically, supplemented by wavelet and FFT analyses, we match the post-transparency BOA acceleration with a wave-particle resonance with a high-amplitude low-frequency electrostatic wave of increasing phase velocity, consistent with that predicted by the Buneman instability.},
doi = {10.1063/1.5028129},
journal = {Physics of Plasmas},
number = 4,
volume = 25,
place = {United States},
year = {2018},
month = {4}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Energetic proton generation in ultra-intense laser�solid interactions
journal, February 2001

  • Wilks, S. C.; Langdon, A. B.; Cowan, T. E.
  • Physics of Plasmas, Vol. 8, Issue 2, p. 542-549
  • DOI: 10.1063/1.1333697

Fast Ignition by Intense Laser-Accelerated Proton Beams
journal, January 2001