skip to main content

DOE PAGESDOE PAGES

Title: Impact of pre-plasma on fast electron generation and transport from short pulse, high intensity lasers

Previous experiments and modeling examining the impact of an underdense, pre-formed plasma in laser-plasma interactions have shown that the fast electrons are generated with energies higher than predicted by ponderomotive scaling. In this paper, we report on experiments using the Texas Petawatt high intensity (150 fs, 1.5 × 10 20 W cm -2) laser pulse, which were conducted to examine the mechanism for accelerating these high energy electrons. These experiments gauge the impact a controlled low density pre-formed plasma has on electron generation with a shorter time scale than previous experiments, 150–180 fs. Electron temperatures measured via magnetic spectrometer on experiment were found to be independent of preformed plasma. Supplemental computational results using 1D PIC simulations predict that super-ponderomotive electrons are generated inside a potential well in the pre-plasma. Finally, however, while the potential well is established around 150 fs, the electrons require at least an additional 50 fs to be trapped and heated inside it.
Authors:
 [1] ;  [1] ;  [1] ;  [1] ;  [1] ;  [2] ;  [3] ;  [3] ;  [3] ;  [4] ;  [4] ;  [4] ;  [4] ;  [4] ;  [4] ;  [4] ;  [4] ;  [1] ;  [1]
  1. Univ. of California, San Diego, CA (United States). Center for Energy Research
  2. General Atomics, San Diego, CA (United States)
  3. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  4. Univ. of Texas, Austin, TX (United States). Physics Dept.
Publication Date:
Report Number(s):
LLNL-JRNL-737084
Journal ID: ISSN 0029-5515; 888284
Grant/Contract Number:
AC52-07NA27344; NA0001858
Type:
Accepted Manuscript
Journal Name:
Nuclear Fusion
Additional Journal Information:
Journal Volume: 56; Journal Issue: 1; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of California, San Diego, CA (United States); Univ. of Texas, Austin, TX (United States)
Sponsoring Org:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; laser plasma interaction; inertial confinement fusion; pre-plasma
OSTI Identifier:
1458693
Alternate Identifier(s):
OSTI ID: 1238833