Direct Unfolding Determination of Energy Spectra for Laser Compton Slant-Scattering ??-Ray Beams Using a LaBr3 Detector

摘要:      A 3-inch × 4-inch LaBr₃ detector was employed to characterize the energy distributions of quasi-monoenergetic 𝛾-rays generated at the Shanghai Laser Electron Gamma Source (SLEGS), part of the Shanghai Synchrotron Radiation Facility. Systematic calibration of the detector’s response was conducted at the China Institute of Atomic Energy using monoenergetic 𝛾-rays from (p,𝛾) nuclear reactions on LiF, ²⁷Al, and ¹³C targets. Energy spectrum unfolding was performed through an iterative matrix inversion algorithm, employing the detector’s monoenergetic response functions as kernel elements in the linear equation system. This approach facilitated direct reconstruction of 𝛾-ray energy spectra from raw detector signals. Validation experiments comparing LaBr₃ and BGO detector reconstructions under identical conditions revealed strong agreement between the two detection systems. The methodology successfully characterized 𝛾-ray beam energy profiles resulting from slant-scattering processes at SLEGS, demonstrating robust performance in complex analysis.