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nm nm oscillation sensitivity. K. Hiraide (Kyoto Univ.). Condition off-axis 2.5deg (04b, 40GeV) NEUT4.5 # of nm int. ~ 2200 events/22.5kt/yr 5yr exposure. Event selection criteria. Standard SK cuts: Fully contained in fiducial volume of 22.5kt Evis>30MeV 1ring m -like.
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nmnm oscillation sensitivity K. Hiraide (Kyoto Univ.) • Condition • off-axis 2.5deg (04b, 40GeV) • NEUT4.5 • # of nm int. ~ 2200 events/22.5kt/yr • 5yr exposure
Event selection criteria • Standard SK cuts: • Fully contained in fiducial volume of 22.5kt • Evis>30MeV • 1ring m-like Reconstructed energy spectrum of FCFV 1R m-like events in case of null oscillation (hatched: non-QE component)
Oscillation analysis • Extended maximum likelihood N : observed number of 1R m-like events Nexp(sin2 2q, Dm2) : expected number of 1R m-like events P(E; sin2 2q, Dm2) : probability density function (PDF) for energy spectrum Ei : reconstructed energy of i-th event (i=1,…,N) Assumed 2-n oscillation
Sensitivity (stat. only) In case of true (sin2 2q, Dm2)=(1.0, 2.7x10-3 eV2) Energy spectrum Allowed region * best fit point -- 68%CL (Dln L=0.5) -- 90%CL (Dln L=1.36) -- 99%CL (Dln L=3.32) + 1R m-like events -- best fit spectrum (hatched: non-QE component)
Sensitivity (stat. only) Assumed sin2 2q=1.0 sin2 2q sensitivity Dm2 sensitivity Expected 90%CL sensitivity of oscillation parameter as a function of true Dm2 d(sin2 2q)~0.009, d(Dm2)~5x10-5 eV2 @Dm2=2.7x10-3 eV2
Energy spectrum distortion In case of true (sin2 2q, Dm2)=(1.0, 2.7x10-3 eV2) + 1R m-like events -- best fit The ratio of the measured spectrum to the expected one without neutrino oscillation (w/o non-QE subtraction)