High-rate neutrino detectors for neutrino factories

Three types of high-rate neutrino detectors for neutrino interaction physics at neutrino factories are discussed. High-performance general-purpose detectors might collect event samples of the order of a billion events or more. This could greatly improve on the existing analyses of neutrino interactions and also lead to new and important analysis topics including, for example, precise determinations of the CKM matrix elements |Vub| and |Vcb|. The potential of such general-purpose detectors is illustrated with reference to a previously discussed detector (B.J. King, Neutrino physics at a Muon Colliders, Proceedings of the Workshop on Physics at the First Muon Collider and Front End of a Muon Collider, Fermilab, November 6–9, 1997) that is structured around a novel and compact vertexing and tracking neutrino target comprising a stack of CCD pixel devices. Design ideas and prospects are also discussed for two types of specialized detectors: (i) polarized targets filled with polarized solid protium–deuterium (HD), for unique and powerful studies of the nucleon's spin structure, and (ii) fully active liquid tracking targets with masses of several tonnes for precise determinations of the weak mixing angle, sin2θW, from the total cross-section for neutrino–electron scattering. All three detector types pose severe technical challenges but their utilization could add significantly to the physics motivation for neutrino factories.