Manipulation of the spatial distribution of laser-accelerated proton beams by varying the laser intensity distribution
Artikel i vetenskaplig tidskrift, 2016

We report on a study of the spatial profile of proton beams produced through target normal sheath acceleration using flat target foils and changing the laser intensity distribution on the target front surface. This is done by either defocusing a single laser pulse or by using a split-pulse setup and irradiating the target with two identical laser pulses with variable spatial separation. The resulting proton beam profile and the energy spectrum are recorded as functions of the focal spot size of the single laser pulse and of the separation between the two pulses. A shaping of the resulting proton beam profile, related to both an increase in flux of low-energy protons in the target normal direction and a decrease in their divergence, in one or two dimensions, is observed. The results are explained by simple modelling of rear surface sheath field expansion, ionization, and projection of the resulting proton beam.

Författare

B. Aurand

Heinrich Heine Universitat

Lunds Universitet

L. Senje

Lunds Universitet

Krister Svensson

Lunds Universitet

M. Hansson

Lunds Universitet

A. Higginson

University of Strathclyde

Arkady Gonoskov

Chalmers, Fysik, Teoretisk fysik

Mattias Marklund

Chalmers, Fysik, Teoretisk fysik

A. Persson

Lunds Universitet

O. Lundh

Lunds Universitet

D. Neely

Rutherford Appleton Laboratory

P. McKenna

University of Strathclyde

C.G. Wahlström

Lunds Universitet

Physics of Plasmas

1070-664X (ISSN) 1089-7674 (eISSN)

Vol. 23 023113

Fundament

Grundläggande vetenskaper

Ämneskategorier

Atom- och molekylfysik och optik

Fusion, plasma och rymdfysik

DOI

10.1063/1.4942032