Data Analysis of Tracks of Heavy Ion Particles in Timepix Detector

Abstract

In this paper, we describe some of the computational challenges that need to be addressed when developing active Space Radiation Monitors and Dosimeters using the Timepix detectors developed by the Medipix2 Collaboration at CERN. Measurement of the Linear Energy Transfer (LET), the source and velocity of incident ionizing radiation, are of initial interest when developing such operational devices because they provide the capability to calculate the Dose-equivalent, and to characterize the radiation field for the design of radiation protective devices. In order to facilitate the LET measurement, we first propose a new method for calculating azimuth direction and polar angle of individual tracks of penetrating charged particles based on the pixel clusters they produce. We then describe an energy compensation method for heavy ion tracks suffering from saturation and plasma effects. Finally, we identify interactions within the detector that need to be excluded from the total effective Dose-Equivalent assessment. We make use of data taken at the HIMAC (Heavy Ion Medical Accelerator Center) facility in Chiba, Japan and NSRL (NASA Space Radiation Laboratory) at the Brookhaven National Laboratory in New York, USA for evaluation purposes.