Paper detail

Getting at large theta_13 with almost maximal theta_23 from tri-bimaximal mixing

We introduce a small correction term, δM_ν, in the neutrino sector and examine whether a large θ_13 and an almost maximal θ_23 can simultaneously be obtained starting from the tri-bimaximal neutrino mixing. It is found that one can easily gain θ_13 \simeq 10^\circ, which is favored by the recent T2K experiment, by taking account of the enhancement due to the degeneracy among three neutrino masses. We also find that (δM_ν)_22=(δM_ν)_33 is a key condition for θ_23 \simeq 45^\circ.