NaI (Tl) Calorimeter Calibration and Simulation for Coulomb Sum Rule Experiment in Hall-A at Jefferson Lab

TL;DR

This paper details the calibration and simulation of a NaI (Tl) calorimeter used in electron scattering experiments at Jefferson Lab, enabling precise measurements of nuclear response functions across various targets.

Contribution

It introduces a comprehensive calibration procedure and simulation validation for the NaI (Tl) calorimeter in the context of Coulomb Sum Rule experiments.

Findings

Achieved a calorimeter energy resolution of about 3% at 1 GeV.

Successfully calibrated NaI (Tl) detector blocks with initial signal issues.

Validated detector performance through comparison with detailed simulations.

Abstract

A precision measurment of inclusive electron scattering cross sections was carried out at Jefferson Lab in the quasi-elastic region for ${^4}$He, ${^{12}}$C, ${^{56}}$Fe and ${^{208}}$Pb targets. Longitudinal ($R_{L}$) and transverse ($R_{T}$) response functions of nucleon were extracted in the momentum transfer range 0.55 GeV/c$\le$$|q|$$\le$1.0 GeV/c. To achieve the above goal, a NaI (Tl) calorimeter was used to distinguish good electrons from background including pions and low energy electrons rescattered from walls of the spectrometer magnets. Due to a large set of kinematics and changes in HV settings, a number of calibrations were performed for the NaI (Tl) detector. Corrections for a few blocks of NaI (Tl) with bad or no signal were applied. The resolution of NaI (Tl) detector after calibration reached $\frac{\delta E}{\sqrt{E}} \approx 3\%$ at E=1 GeV. The performance of NaI (Tl) detector was compared with a simulation.