Multi-coincidence System of Ionization Radiation Detectors Based on Advanced Position Sensitive Detectors

Abstract

Detection of ionizing radiation is an issue which affects many areas of a human life. Significant progress in detection capabilities was caused by the development of electronics in recent decades. This dissertation thesis, which deals with the design of the Multi-coincidence system of ionizing radiation detectors, follows this trend. The Multi-coincidence system of ionizing radiation detectors combines extraordinary technologies and due to using advanced electronics allows them to operate in a synchronous mode that brings new possibilities in radiation environment investigation, such as incoming direction or separation of particle types in a mixed radiation field. This dissertation thesis summarizes the development from the basic design, through hardware, firmware and software for user control as well as basic data processing. The functionality of the design is verified on a prototype and demonstrated by measurements whose results are also presented. The design is based on “sandwich” structure composed of two detection parts in closed geometry – a silicon pixel detector Timepix and a plastic scintillator covered by silicon photomultipliers. The pixel detector Timepix is a device with excellent parameters and unrivaled ability of detection and recognition of different types of radiation. The disadvantage is the detection material itself which does not allow to effectively detect certain types of radiation, such as neutrons. This is the domain of scintillation detectors. Recent optical sensors called silicon photomultipliers offers possibility for detecting of the scintillating light by small-size device. The Multi-coincidence system is a compact portable detection unit which can be used in applications where small dimensions are a significant requirement. Furthermore, it is insensitive to a magnetic field. Utilization of the system can be found in different areas from searching of radiation threats, through dosimetry to space weather monitoring. Keywords: