Micron-scale fast electron filaments and recirculation determined from rear-side optical emission in high-intensity laser-solid interactions

C. Bellei, S. R. Nagel, S. Kar, A. Henig, S. Kneip, C. Palmer, A. Saevert, L. Willingale, D. Carroll, B. Dromey, J. S. Green, K. Markey, P. Simpson, R. J. Clarke, H. Lowe, D. Neely, C. Spindloe, M. Tolley, M. C. Kaluza, S. P. D. ManglesP. McKenna, P. A. Norreys, J. Schreiber, M. Zepf, J. R. Davies, K. Krushelnick, Z. Najmudin

Research output: Contribution to journalArticle

10 Citations (Scopus)
24 Downloads (Pure)

Abstract

The transport of relativistic electrons generated in the interaction of petawatt class lasers with solid targets has been studied through measurements of the second harmonic optical emission from their rear surface. The high degree of polarization of the emission indicates that it is predominantly optical transition radiation (TR). A halo that surrounds the main region of emission is also polarized and is attributed to the effect of electron recirculation. The variation of the polarization state and intensity of radiation with the angle of observation indicates that the emission of TR is highly directional and provides evidence for the presence of mu m-size filaments. A brief discussion on the possible causes of such a fine electron beam structure is given.

Original languageEnglish
Article number073016
Number of pages12
JournalNew Journal of Physics
Volume12
DOIs
Publication statusPublished - 21 Jul 2010

Keywords

  • generated fast electrons
  • transition radiation
  • fast-igniter
  • targets
  • plasma
  • transport
  • pulses

Cite this