Tests of a polarimeter for laser-driven proton beams at the 45-MeV cyclotron JULIC

A novel method of laser-plasma acceleration employing dynamically polarized gas-jet targets (HCl/HBr gas) has been proposed to generate 100-MeV polarized proton beams. To achieve the beam polarization measurement in laser-plasma experiments at multi-Petawatt lasers, we have developed a polarimeter based on p-Carbon scattering, detected with the help of Solid-State Nuclear Track Detectors (SSNTDs), and tested it with 45 MeV polarized proton beam at JULIC. The most demanding part of the data analysis is to identify protons and carbon ions on top of large background of secondary particles. In this paper we compare the performance of the proton polarimeter based on SSNTDs to a low energy polarimeter (LEP) at JULIC, giving a first calibration of the analyzing power for the new polarimeter at 45 MeV. The polarimeter based on SSNTDs has been extended to He-3 ion beams and applied successfully at the PHELIX laser facility, GSI-Darmstadt.