A tabletop, ultrashort pulse photoneutron source driven by electrons from laser wakefield acceleration

Abstract

Relativistic electron beams driven by laser wakefield acceleration were utilized to produce ultrashort neutron sources. The experiment was carried out on the 38 fs, ∼0.5 J, 800 nm Ti:Sapphire laser in the 10 TW UT3 laser lab at University of Texas at Austin. The target gas was a high density pulsed gas jet composed of 90% He and 10% N2. The laser pulse with a peak intensity of 1.5 × 1018 W/cm2 interacted with the target to create a cylindrical plasma channel of 60 μm radius (FWHM) and 1.5 mm length (FWHM). Electron beams of ∼80 pC with the Gaussian energy distribution centered at 37 MeV and a width of 30 MeV (FWHM) were produced via laser wakefield acceleration. Neutron fluences of ∼2.4 × 106 per shot with hundreds of ps temporal length were generated through bremsstrahlung and subsequent photoneutron reactions in a 26.6 mm thick tungsten converter. Results were compared with those of simulations using EPOCH and GEANT4, showing agreement in electron spectrum, neutron fluence, neutron angular distribution and conversion rate.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 01, 2017
Source ID
10.1016/j.mre.2017.10.003

Entities

People

  • B.m. Hegelich
  • Hai-En Tsai
  • I. Pomerantz
  • J.m. Shaw
  • L.a. Labun
  • M.c. Downer
  • P. Poth
  • T. Toncian
  • Tianhong Wang
  • X.j. Jiao
  • X.m. Wang

Organizations

  • Air Force Office of Scientific Research
  • National Nuclear Security Administration
  • Technical University of Darmstadt
  • Tel Aviv University

Tags

Fields of Study

  • Physics

Readers

  • Optical Physics and Photonics.
  • Pulsed Power and Plasma Physics.
  • Solar Physics

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Microelectronics