Negative muon induced elemental analysis by muonic X-ray and prompt gamma-ray measurements

Abstract

When a negatively charged muon stopped in a material, muonic atom, which has one muon in place of an electron in the atomic system, is formed. After muon deexcitation process with muonic X-ray emission, the muon reaches to the muonic 1 s state, and the muon is absorbed in the nucleus. As a result, highly excited nucleus is produced, and the nucleus emits neutrons and gamma-rays. In this work, we determined elemental depth profiling of gold concentrations on archeological sample, an old Japanese coin, by measuring gamma-ray intensities emitted from activated nucleus with various incident muon energies.