A novel active collimator for compton-suppressed clover HPGe detector and its role in a hybrid gamma detector array

Abstract

A new active collimator (AC) detector has been designed as a replacement of the heavy metal collimator for the Compton-suppressed clover High Purity Germanium (HPGe) detector, aiming to enhance the performance of the 4π hybrid gamma detector array for nuclear spectroscopy experiments. This replacement promises enhanced functionality and efficiency in detecting gamma radiation within the detector array. By utilizing ACs in combination with Compton-suppressed clover HPGe and LaBr3(Ce) detectors, a highly effective setup can be established for a γ-ray multiplicity filter for angular momentum selection in heavy ion collision reactions. This configuration offers notable advantages when studying weak band structures that undergo decay through high-cut multiplicity γ-ray events. Moreover, by summing the energy deposited in all detectors, the hybrid array can also be effectively utilized for calorimetric applications in specific measurements. We have designed and characterized an AC with a Compton-suppressed clover HPGe detector. Significantly, when using the AC configuration with the 60Co source, the absorption of γ-rays in AC and the peak-to-total ratio in clover HPGe were found to be similar to that obtained with the standard design incorporating the heavy metal configuration. The advantages of employing the AC for higher multiplicity events were demonstrated through GEANT4 simulations. The simulations were conducted for the entire array, and the potential benefits are thoroughly discussed, highlighting the improved performance achievable with the AC configuration.