High precision flux measurements in conventional neutrino beams: the ENUBET project

The challenges of precision neutrino physics require measurements of absolute neutrino cross sec- tions at the GeV scale with exquisite (1%) precision. This precision is presently limited to by the uncertainties on neutrino flux at the source. A reduction of this uncertainty by one order of mag- nitude can be achieved monitoring the positron production in the decay tunnel originating from the K e 3 decays of charged kaons in a sign and momentum selected narrow band beam. This novel technique enables the measurement of the most relevant cross-sections for CP violation ( ν e and ̄ ν e ) with a precision of 1% and requires a special instrumented beam-line. Such non-conventional beam-line will be developed in the framework of the ENUBET Horizon-2020 Consolidator Grant, recently approved by the European Research Council. We present the Project, the first experimen- tal results on ultra-compact calorimeters that can embedded in the instrumented decay tunnel and the advances on the simulation of the beamline. A rich program of detector R&D; and accelerator- related activities are planned in 2016-2021.