Thermal neutron measurements by Timepix detector in H4IRRAD at CERN

Timepix, a pixel detector, was installed in the H4IRRAD irradiation area at CERN to study its response to a mixed radiation field. The measured data were compared to Monte Carlo simulations performed by the FLUKA code. This paper focuses on thermal neutron fluence measurement and simulation studies. The observed disagreement between the measured and simulated thermal neutron fluence of a factor 2.6 is discussed and the influence of the shielding material composition on this disagreement is studied.