Measurement of π−and π+ photoproduction in deuterium at large momentum transfer for E = 1.7−5.6 GeV

Single-π − and -π + photoproduction from deuterium has been measured at energies E = 1.7−5.6 GeV and momentum transfers |t|= 0.4−5.6 (GeV/c)2. The ratio π −/π + for data taken at E = 3.4 GeV is presented. Also the ratio of the π + from hydrogen to the π + from deuterium is extracted to examine the nucleon spectator assumption used in the cross-section ratio analysis. Results are discussed in conjunction with the existing measurements with frameworks ranging from a hadronic description to parton constituent models which successfully characterize the scaling behaviors observed in the exclusive measurements.