Photoproduction of charged pions from the deuteron

Abstract

The photoproduction of the charged pions from the deuteron has been studied with the Neutral Kaon Spectrometer (NKS) and the Neutral Kaon Spectrometer 2 (NKS2) at the Research Center for Electron Photon Science, Tohoku University (ELPH) which was previously known as the Laboratory of Nuclear Science (LNS-Tohoku) using the GeV-region tagged photon beam. The total cross section for the quasi-free (QF) π + π − photoproduction from the deuteron was measured with NKS in the energy region from 0.8 to 1.1 GeV. The cross section for the double Δ excitation in the intermediate state was derived in the analysis of the non-quasi-free (NQF) process, in which two nucleons of the deuteron share the energy of the incident photon. The prospect of the measurements of double pion photoproduction with NKS2 and upgraded NKS2 is discussed. The pion photoproduction from the nucleon has been investigated both experimentally and theoreti- cally for the study of the nucleon resonances for tens of years. The contribution of the double pion photoproduction from the proton is dominant in the energy region higher than 0.6 GeV. The π + π − photoproduction cross section accounts for approximately 30 percent of the total photoproduction in this energy region.