HRS optics optimization method for Coulomb sum rule (CSR) experiment in JLab Hall-A

In order to study the acceptance and calculate cross sections for CSR experiment, one needs to obtain target variables on the target plane of the spectrometer. Target variables can be reconstructed from focal plane variables with optics. In principle, the optics is the mathematical expression of the magnetic field of HRS. The optics optimization method which minimizes χ² of TgVar_data-TgVa_theory to determine the better optics matrix elements for CSR experiment was studied. The optimization results show a good agreement between the data and theoretical values.