Optoelectronics for neutron detectors based on superheated emulsions

¹ School of Engineering, University of Pisa, Italy
² Italian National Institute of Nuclear Physics, Pisa, Italy

^* andrea.chierici@ing.unipi.it

Published online: 21 November 2023

Abstract

This paper presents the design, assembly, and performance investigation of an optoelectronic readout system specifically designed to enhance the real-time readout capabilities of Superheated Drop Detectors (SDDs). SDDs as fast neutron detectors have been widely used in different areas such as homeland security, radiation protection, and personal dosimetry. In homeland security, SDDs showed the potential of detecting prompt fission neutrons from special nuclear materials in radiation portal monitor systems, possibly positioning them as a valuable alternative to He-3 detectors. In radiation protection and personal dosimetry, downsized SDDs may be employed to assess the level of exposure of workers in nuclear energy production facilities or as a tool to perform photoneutron contamination studies of medical and research accelerators. The proposed readout system utilizes lightemitting diodes to illuminate the detectors, while photodiodes are employed to record the integral value of scattered light resulting from bubbles’ formation, a consequence of neutron interaction. To validate the behavior of the system, comprehensive field testing was conducted after assembling and integrating it with custom-made 3D printed structures tailored for different SDD geometry, and the reader was utilized to examine the optical and detection characteristics of different SDD compositions under various ionizing radiation conditions. The potential to actively read out SDDs in real-time represents a significant advancement for this radiation detection technology, particularly in fields such as radiation protection and industrial applications, and it provides valuable insights for future enhancements in the field of neutron radiation detection.