Fig. 4From: Low-radiation dose XRF excited by MeV protons for cultural heritage samplesPIXRF energy spectra measured for the thick samples with a 0-ppm (blank) (Sample #1), b 1000-ppm (Sample #2) and c 10,000-ppm (Sample #3) Cu using the Ge target. The asterisks (*) indicate the peaks of the scattered primary photonsBack to article page