Analysis of the APEX Experiment Data

The A-Prime Experiment (APEX) took data for the search for dark matter force mediator A’ in the mass range 160-230 MeV decaying to e+e- pairs with statistics corresponding to the signal sensitivity on the level of coupling constant $10^{-9}$. This experiment was carried out in Jefferson Lab experimental hall A in 2019 using the High Resolution Spectrometer (HRS) pair. We will present the results on the magnetic optics for accurate reconstruction of the particle momenta for the APEX configuration of the HRS spectrometers with the septum magnet. Preliminary results show that angular reconstruction could be accomplished with a precision of 0.5 msr or better.