Detection of short lived radioisotopes as a fast diagnostic for intense laser-solid interactions

Abstract

As a diagnostic of high-intensity laser interactions (>1019Wcm−2), the detection of radioactive isotopes is regularly used for the characterization of proton, neutron, ion, and photon beams. This involves sample removal from the interaction chamber and time consuming post shot analysis using NaI coincidence counting or Ge detectors. This letter describes the use of in situ detectors to measure laser-driven (p,n) reactions in Al27 as an almost real-time diagnostic for proton acceleration. The produced Si27 isotope decays with a 4.16s half-life by the predominantly β+ emission, producing a strong 511keV annihilation peak.