Neutrino Oscillation Parameters After High Statistics KamLAND Results

Abstract

We do a re-analysis to asses the impact of the results of the Borexino experiment and the recent 2.8 KTy KamLAND data on the solar neutrino oscillation parameters. The current Borexino results are found to have no impact on the allowed solar neutrino parameter space. The new KamLAND data causes a significant reduction of the allowed range of $\Delta m_{21}^2$, determining it with an unprecedented precision of 8.3% at 3$\sigma$. The precision of $\Delta m_{21}^2$ is controlled practically by the KamLAND data alone. Inclusion of new KamLAND results also improves the upper bound on ${\sin }^2{\theta }_{12}$, but the precision of this parameter continues to be controlled by the solar data. The third mixing angle is constrained to be ${\sin }^2{\theta }_{13}<0.063$ at $3\sigma$ from a combined fit to the solar, KamLAND, atmospheric and CHOOZ results. We also address the issue of how much further reduction of allowed range of $\Delta m_{21}^2$ and ${\sin }^2{\theta }_{12}$ is possible with increased statistics from KamLAND. We find that there is a sharp reduction of the $3\sigma$ ``spread'' with enhanced statistics till about 10 KTy after which the spread tends to flatten out reaching to less than 4% with 15 KTy data. For ${\sin }^2{\theta }_{12}$ however, the spread is more than 25% even after 20 KTy exposure and assuming ${\theta }_{12}<\pi /4$, as dictated by the solar data. We show that with a KamLAND like reactor ``SPMIN'' experiment at a distance of $\sim$ 60 km, the spread of ${\sin }^2{\theta }_{12}$ could be reduced to about 5% at $3\sigma$ level while $\Delta m_{21}^2$ could be determined to within 4%, with just 3 KTy exposure.

15 pages, 5 figures

References in corpus (4)

• Precision Measurement of Neutrino Oscillation Parameters with KamLAND
• Phenomenology with Massive Neutrinos
• Contrasting solar and reactor neutrinos with a non-zero value of theta13
• SNO and the solar neutrino problem

Cited by in corpus (31)

• Revisiting Bimaximal Neutrino Mixing in a Model with S4 Discrete Symmetry
• Fermion Masses and Mixings in a S4 Based Model
• A Simplest A4 Model for Tri-Bimaximal Neutrino Mixing
• Lepton Flavour Violation in Models with A4 Flavour Symmetry
• Phenomenological Consequences of See-Saw in S4 Based Models
• The Interplay Between GUT and Flavour Symmetries in a Pati-Salam x S4 Model
• Identifying neutrino mass hierarchy at extremely small theta(13) through Earth matter effects in a supernova signal
• Tri-Bimaximal Lepton Mixing and Leptogenesis
• Lepton Flavour Violation in a Supersymmetric Model with A4 Flavour Symmetry
• Majorana Phases and Leptogenesis in See-Saw Models with A_4 Symmetry
• Flavor Composition of UHE Neutrinos at Source and at Neutrino Telescopes
• The Interplay Between the "Low" and "High" Energy CP-Violation in Leptogenesis
• Large U_{e3} and Tri-bimaximal Mixing
• Phenomenological consequences of four zero neutrino Yukawa textures
• Running Effects on Lepton Mixing Angles in Flavour Models with Type I Seesaw
• Lepton Masses in a Minimal Model with Triplet Higgs Bosons and $S_3$ Flavor Symmetry
• Neutrinoless Double Beta Decay and H^{\pm\pm}\to {l'}^\pm l^\pm Decays in the Higgs Triplet Model
• On the Vanishing of the CP Asymmetry in Leptogenesis due to Form Dominance
• Bayesian Constraints on theta_{13} from Solar and KamLAND Neutrino Data
• Renormalization group evolution of neutrino masses and mixing in seesaw models: A review
• Neutralino reconstruction in supersymmetry with long-lived staus
• Optimized Two-Baseline Beta-Beam Experiment
• Spontaneous R-Parity Violation, $A_4$ Flavor Symmetry and Tribimaximal Mixing
• Theoretical Models of Neutrino Mixing: Recent Developments
• Unitarity violation in sequential neutrino mixing in a model of extra dimensions
• Type I and $new$ seesaw in left-right symmetric theories
• Phenomenology of Discrete Flavour Symmetries
• Spontaneous R-parity violating type III seesaw
• Determination of the Third Neutrino-Mixing Angle θ_(13) and its Implications
• Supernovae as laboratories for neutrino properties
• Impact on Astrophysics and Elementary Particle Physics of recent and future solar neutrino data