Zenith angle dependence on cosmic-ray background in HPGe gamma spectrometers by using GEANT4 simulation.

Area of Science:

• Nuclear Physics
• Detector Technology
• Radiation Detection

Background:

• Cosmic-ray induced background significantly impacts the sensitivity of High-Purity Germanium (HPGe) gamma spectrometers.
• Understanding and mitigating this background is crucial for precise radiation measurements.

Purpose of the Study:

• To investigate the influence of zenith angle variations on cosmic-ray induced background in HPGe gamma spectrometers.
• To validate experimental measurements with GEANT4 simulations for accurate background assessment.

Main Methods:

• Utilized a coincidence technique with plastic scintillator-Germanium detectors and an HPGe detector within a lead shield.
• Calculated the zenith angle based on scintillator dimensions and detector positioning.
• Performed measurements with a specific plastic scintillator configuration (80cm x 80cm) and compared with GEANT4 simulations.

Main Results:

• Experimental measurements showed good agreement with GEANT4 simulation data for the energy spectrum from 0.05 to 47 MeV.
• The study quantified the impact of zenith angle on cosmic-ray background events.

Conclusions:

• Zenith angle variations have a notable effect on cosmic-ray induced background in HPGe gamma spectrometers.
• The validated simulation approach and experimental findings offer valuable insights for optimizing detector shielding and configuration to minimize background noise.