Development of the Low Granularity Pair Spectrometer counters in Hall D at Jlab

The pair spectrometer in the photon beam line of Hall D at Jlab is designed to calibrate and monitor the linear beam polarization and the relative tagging efficiency of the photon tagger via a well known electron-positron pair production measurement. This system includes a thin foil converter, a dipole magnet, and two identical left and right arm detector packages. Each detector package covers the electron or position energy from 3 GeV to 6.25 GeV, which consists of a front detector array for fine position resolution and a back scintillating hodoscopes for fast timing. This presentation will focus on the development and construction of the Low Granularity Pair Spectrometer counters.