Large Size GEM for Super Bigbite Spectrometer (SBS) Polarimeter for Hall A 12 GeV program at JLab

TL;DR

This paper details the design, construction, and testing of large Gas Electron Multiplier (GEM) detectors for the Proton Polarimeter Back Tracker in the Super Bigbite Spectrometer at JLab, enhancing particle detection capabilities.

Contribution

It presents the development of large-scale GEM modules specifically designed for the SBS Proton Polarimeter, including prototype testing and performance evaluation.

Findings

Successful construction of 60 x 200 cm2 GEM chambers.

Prototype tests show promising performance metrics.

Ongoing development for integration into the SBS system.

Abstract

We report on the R&D effort in the design and construction of a large size Gas Electron Multiplier (GEM) for the Proton Polarimeter Back Tracker (BT) of the Super Bigbite Spectrometer (SBS) in Hall A at Thomas Jefferson National Laboratory (JLab). The SBS BT GEM trackers consist of two sets of five large GEM xchambers of size 60 x 200 cm2. The GEM chamber is a vertical stack of four GEM modules, each with an active area of 60 x 50 cm2. We have built and tested several prototypes and the construction of GEM modules for SBS BT is ongoing. We describe in this paper the design and construction of the GEM module prototype as well as the preliminary results on performance from tests carried out in our detector lab and during test beam at Fermi National Laboratory (Fermilab).