ENUBET’s Multi Momentum Secondary Beam Line

In order to study the remaining open questions concerning CP violation and neutrino mass hierarchy, as well as to search for physics beyond the Standard Model, future experiments require precise measurements of the neutrino interaction cross-sections in the GeV regime. The absence of a precise knowledge of the neutrino flux (mainly due to uncertainties on the parent hadrons production cross sections) currently limits this measurement to a 5-10% uncertainty level. The ENUBET project is proposing a novel facility, capable of constraining the neutrino flux normalization through the precise monitoring of kaon decay products in an instrumented decay tunnel. The collaboration has conducted numerous studies using a beamline with a central kaon momentum of 8.5 GeV/c and a ±10% momentum spread. We present here an alternative beam-line design, broadening the range of kaons to include momenta of 4, 6, and 8.5 GeV/c, thus allowing ENUBET to explore cross sections over a much larger momentum range. Specifically, we discuss the status of this design, the optimization studies performed, the early results, and the expected performance in terms of kaon mesons and neutrino rates.