Characterisation of permanent magnetic quadrupoles for focussing proton beams

Abstract

High intensity laser driven proton beams are at present receiving much attention. The reasons for this are many but high on the list is the potential to produce compact accelerators. However two of the limitations of this technology is that unlike conventional nuclear RF accelerators lasers produce diverging beams with an exponential energy distribution. A number of different approaches have been attempted to monochromise these beams but it has become obvious that magnetic spectrometer technology developed over many years by nuclear physicists to transport and focus proton beams could play an important role for this purpose. This paper deals with the design and characterisation of a magnetic quadrupole system which will attempt to focus and transport laser-accelerated proton beams.

Towards Laser Driven Hadron Cancer Radiotherapy: A Review of Progress

“…A similar outcome could be more easily achieved using small quadrupole or pulsed solenoid magnets, an approach that is being developed by several groups including the authors of this paper [56][57][58] also showing how the proton beam can be captured and transported. More about transport of laser produced proton beams will be discussed in Section 4.…”

Protons Acceleration by CO2 Laser Pulses and Perspectives for Medical Applications

“…Simulations and experiments are presently being developed to explore the feasibility of transport of an optically accelerated protons bunch reaching the beam quality required for irradiation and for injection into a post-acceleration device [Melone (2011);Nishiuchi (2010);Schollmeier (2008)]. The reduction of the energy spread with a longitudinal phase space rotation provided by a synchronized RF was also proved [Noda (2008)].…”