Boson Photoproduction Experiments

Abstract

A general discussion is presented of all possible experiments on photoproduction of spin-zero bosons from spin-\textonehalf{} fermions. Both scalar and pseudoscalar bosons are considered. The $M$ matrix is constructed in terms of four particularly convenient invariants. There are altogether 64 different experiments possible. Of these, 16 are needed to measure all the bilinear combinations of the coefficients of the invariants in the $M$ matrix. To determine the coefficients themselves (not necessarily unambiguously) seven experiments have to be carried out. The 64 observables are given in terms of the bilinear combinations of the coefficients. An extensive list of experiments is then given each of which determines the parity of the boson participating in the process. All of these experiments require polarized photon sources, and even the simplest one requires the measurement of recoil fermion polarization and the use of a polarized target, although not simultaneously. Sets of seven experiments are then constructed to determine the four coefficients in the $M$ matrix. The simplest of these sets implies the same experimental requirements as the simplest parity experiment. The simplest set of 16 experiments giving all bilinear combinations of the coefficients involves in addition also simultaneously recoil nucleon polarization measurements and the use of polarized targets.