Will T2KK see new physics? Hiroaki Sugiyama (Theory group, KEK) Ref: N. Kitazawa, HS, and O. Yasuda, hep-ph/0606013

Introduction Future oscillation experiments search for tiny effects of high-precision measurements of oscillation probabilities Are they sensitive to also new physics? unitarity violation near detector non-standard interaction with source non-standard interaction with matter non-standard interaction with detector We consider only non-standard matter effect in model-independent way

Non-standard matter effect Hamiltonian in flavor basis : matter density

Low energy (ex. reactor) Medium energy (ex. T2KK) High energy (ex. neutrino factory) vacuum osc. significant effects? vacuum osc. is suppressed large non-standard effect pure measurement of oscillation parameters (in far future)

no phases for simplicity Constraint on no phases for simplicity is bounded stringently by experiments with charged leptons?? NO! (from model-independent viewpoint) ex.: dim-8 op. with higgs indep. constraint by experiments with neutrinos S. Davidson et al., JHEP 0303, 011 (2003) A. Friedland et al., Phys. Rev. D72, 053009 (2005) is allowed!! large effect in T2KK?

Setup three epsilons that can be (others are zero) no phases parameters are fixed probabilities are obtained numerically perturbation with respect to is not reliable for

Oscillation probabilities with (off-axis) Probs. with have similar size to standard prob. with T2K can not give clear evidence for non-standard effects How about T2KK?

region for off-axis beam at a detector in Korea (a) (g) Prob. with can be much larger than standard prob.. (h) clear evidence is important in this energy range

Difference between and (g) (i) (g) (i) gives the difference between probs. for and

higher energy region (on-axis beam) and are also important in this energy range

T2KK(1000km) vs. MINOS(735km) ongoing exp. Non-standard effect in T2KK is larger than that in MINOS Korean detector can be placed for off-axis beam better sensitivity Even if MINOS does not see (see) the effect, there is a chance for T2KK to see (improve) that.

Conclusion In T2KK,　 can give large probability that can not be explained by the standard one with Even after MINOS (735km), T2KK can give new information on non-standard interactions.

Backup

Constraint with atm. and K2K A. Friedland et al., Phys. Rev. D72, 053009 (2005) We can read off measured value true values

Silver channel in neutrino factory(3000km) (g) huge enhancement! is possible!

Two-flavor case ex. silver channel in neutrino factory