Calibration of the T08.XSEC devices by means of Al-foil activation and BCTF measurements

The IRRAD/CHARM irradiation facility in the East experimental area exploits a proton beam of standard intensity 5×10^{11} p/spill slow-extracted from the CERN PS accelerator to the T08 beam line over about 400ms. This document summarizes the procedure employed for the calibration of the Secondary Emission Chamber (XSEC) devices of T08 used to monitor the total proton intensity per spill during facility operation. The presented calibration relies on activation foils and Fast Beam Current Transformer measurements performed with both slow- and fast-extracted beams, as well as document the calibration factors used in the run 2022 of the facility.