Intercomparison of LET spectra measured with Timepix and TEPC in reference radiation field CERF

Radiation field onboard aircraft is composed of many particles (neutrons, protons, alphas, muons, electrons, positrons, and gamma) with large scale of energies. Proper experimental evaluation of the radiation risk is therefore a difficult task requiring a set of dosimeters. For measurement with a single radaition detector, the tissue equivalent proportional counter (TEPC) is usualy used as a reference dosimeter. However, the TEPC device is still big and heavy for routine measurements. We therefore study new methods based on a single silicon chip. From them, Timepix is a very interesting option taking advantage of its ability to record tracks of radiation in the silicon chip in real time. We developed a new method for evaluation of LET in water using Timepix with the single silicon chip. CERF (The CERN's EU Reference Field Facility) is the reference field facility built for calibration of dosimeters used onboard aircraft. We exposed both detectors (TEPC Hawk and Timepix) to the radiation in the same reference positions and compared the results. Good agreement was observed.