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تسجيل مستخدم جديدExceptional Sensitivity to Neutrino Parameters with a Two Baseline Beta-Beam Set-up
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We examine the reach of a Beta-beam experiment with two detectors at carefully chosen baselines for exploring neutrino mass parameters. Locating the source at CERN, the two detectors and baselines are: (a) a 50 kton iron calorimeter (ICAL) at a baseline of around 7150 km which is roughly the magic baseline, e.g., ICAL@INO, and (b) a 50 kton Totally Active Scintillator Detector at a distance of 730 km, e.g., at Gran Sasso. We choose 8B/8Li source ions with a boost factor gamma of 650 for the magic baseline while for the closer detector we consider 18Ne/6He ions with a range of Lorentz boosts. We find that the locations of the two detectors complement each other leading to an exceptional high sensitivity. With gamma=650 for 8B/8Li and gamma=575 for 18Ne/6He and total luminosity corresponding to 5times (1.1 times 10^{18}) and 5times (2.9times 10^{18}) useful ion decays in neutrino and antineutrino modes respectively, we find that our two detector set-up can probe maximal CP violation and establish the neutrino mass ordering if sin^22theta_{13} is 1.4times 10^{-4} and 2.7times 10^{-4}, respectively, or more. The sensitivity reach for sin^22theta_{13} itself is 5.5 times 10^{-4}. With a factor of 10 higher luminosity, the corresponding sin^22theta_{13} reach of this set-up would be 1.8times 10^{-5}, 4.6times 10^{-5} and 5.3times 10^{-5} respectively for the above three performance indicators. CP violation can be discovered for 64% of the possible delta_{CP} values for sin^22theta_{13} geq 10^{-3} (geq 8times 10^{-5}), for the standard luminosity (10 times enhanced luminosity). Comparable physics performance can be achieved in a set-up where data from CERN to INO@ICAL is combined with that from CERN to the Boulby mine in United Kingdom, a baseline of 1050 km.
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