Laser accelerated protons captured and transported by a pulse power solenoid

T Burris-Mog,V Bagnoud,S Busold,M Roth,B Zielbauer,T E Cowan,F Nürnberg,T Herrmannsdoerfer,K Harres,M Sobiella,A Tauschwitz,M Bussmann,G Hoffmeister,O Deppert,M Joost

doi:10.1103/physrevstab.14.121301

Abstract

Using a pulse power solenoid, we demonstrate efficient capture of laser accelerated proton beams and the ability to control their large divergence angles and broad energy range. Simulations using measured data for the input parameters give inference into the phase-space and transport efficiencies of the captured proton beams. We conclude with results from a feasibility study of a pulse power compact achromatic gantry concept. Using a scaled target normal sheath acceleration spectrum, we present simulation results of the available spectrum after transport through the gantry.

Highlights

Over the past decade, there has been extensive research regarding the acceleration of protons driven by intense laser light (I > 1018 W=cm2)
The laser interacts with solid foil targets which leads to the acceleration mechanism known as target normal sheath acceleration (TNSA) [1]
permanent magnet quadrupoles (PMQs) are widely used in conventional accelerator beam lines to correct paraxial beams with small divergences, their magnetic field is on the order of 1 T and cannot sufficiently capture highly divergent protons of more than a few MeV, let alone the 250 MeV protons necessary for proton therapy

Summary

Laser accelerated protons captured and transported by a pulse power solenoid

Using a pulse power solenoid, we demonstrate efficient capture of laser accelerated proton beams and the ability to control their large divergence angles and broad energy range. Because TNSA results in a large diverging proton beam, both applications will require efficient capture and collimation by a focusing element such as a magnetic lens. A pulse power solenoid was used to generate temporally short but intense magnetic fields. The work presented here demonstrates the effectiveness of proton capture and transport by a solenoid pulsed at two different magnetic field strengths, 7.2 and 8.5 T. This pulse power solenoid is a first-generation design and, based on our results, later designs will be optimized.

Published by the American Physical Society

EXPERIMENTAL SETUP

RESULTS AND DISCUSSION