Positron identification in the ENUBET instrumented decay tunnel

The ERC granted ENUBET project aims at developing the technologies to reduce by a factor ∼10 the systematics in neutrino fluxes from conventional beams, allowing measuring the νe (and ν¯¯¯e) cross section with a 1% precision, in the region of interest for future oscillation experiments looking for CP violation. This goal is accomplished by monitoring in an instrumented decay tunnel the high angle positron produced in Ke3 decays of charged kaons, in a sign and momentum selected narrow band beam. After a brief description of the proposed facility, the Monte Carlo simulation of the positron tagger in realistic conditions and a preliminary event reconstruction chain will be described, together with results on the expected signal selection efficiency.