A quasi-monoenergetic compact proton source for probing high energy density states of matter at high repetition rate*

Development of monochromatic laser-driven ion sources is of large interest for many applications such as probing extreme states of matter, proton radiography and medical applications. We report [1] on the generation of narrow energy band, short time duration proton beam operating at high repetition rate at CLPU laser facility (Spain). The protons are generated with an ultrashort-pulse laser interacting with a solid target and converted to a pencil-like narrow-band beam using a compact magnet-based energy selector. We experimentally demonstrate the production of a proton beam with an energy of 500 keV, energy spread well below 10%. The calculated pulse duration downstream the selector is 260 ps. To demonstrate the feasibility of the platform for stopping power measurements in warm dense matter [2], we measure the energy loss of this beam in a solid target and find a good agreement with the theoretical predictions to within a few percent.  Further optimization and improvement of performance of the energy selector platform will be performed at CSU ALEPH laser facility.