Application of the Timepix Detectors for the Detection of Unstable Isotopes in the Fission of 252Cf

Abstract

An experimental study of rare fission modes of 252 Cf was conducted using a hybrid pixel detector system based on Timepix technology. The primary objective was to investigate quaternary fission events, particularly those involving the decay of unstable light charged particles, such as excited states of 7Li and 8Be. The detection setup consisted of a ΔE detector (15μm thick) placed in front of 300μm thick Timepix sensor, offering high spatial resolution (<10μm) and per-pixel energy sensitivity. This configuration enabled the precise reconstruction of angular correlations and decay kinematics, significantly exceeding the capabilities of conventional silicon detectors. In addition to the traditional ΔE−E technique, detailed cluster analysis was performed using pattern recognition methods to identify charged particles, reconstruct their energy, and infer the parent isotopes. Two identical telescopes were positioned face-to-face at a distance of 2 cm from the 252Cf source, covering a limited angular range of about 3∘−5∘ and 140∘−180∘ for the opening angles between coincident LCPs. Due to this restricted geometry, Monte Carlo simulations were done to correct geometrical acceptance and detector response. Trajectory-based angular distribution calculations were also performed for the decay of unstable isotopes and compared with the experimental results.