Present and future of neutrino oscillation experiments

Results of a new study of the discovery potential within mSUGRA parameter space of inclusive searches for SUSY at ATLAS are presented. These results indicate that superior performance is provided by the jets + E_T^miss channel in which no requirements are placed upon lepton multiplicity. The sensitivity of this and other channels is mapped in m₀ - m_1/2 parameter space for four different values of tan(β) with similar performance being obtained in all cases. Inclusive measurements of the effective mass scale M_susy^eff and total production cross-section σ_susy of supersymmetric particles are also discussed and results presented of a study of the likely measurement precisions.     

Probing the neutrino mass matrix in next-generation neutrino oscillation experiments

We review the current status of the neutrino mass and mixing parameters needed to reconstruct the neutrino mass matrix. A comparative study of the precision in the measurement of oscillation parameters expected from the next-generation solar, atmospheric, reactor-and accelerator-based neutrino experiments is presented. We discuss the potential of 0νββ experiments in determining the neutrino mass hierarchy and the importance of a better ϑ ₁₂ measurement for it. The text was submitted by the author in English.     

Long—baseline neutrino oscillation experiments

The status and progress of accelerator long—baseline experiments on neutrino oscillation is discussed. Emphasis is given to the one running experiment in this class, the KEK to Kamioka experiment. Since this example establishes the technique of long—baseline experiments in general, some details of timing and beam aiming are discussed. Preliminary results of this experiment are reviewed. Status of other projects is presented.     

Constraints on long-baseline neutrino oscillations from the results of neutrino oscillation experiments

It is shown that in the two schemes with four massive neutrinos which are compatible with the results of all neutrino oscillation experiments, the probabilities of disappearance and appearance in long-baseline experiments are severely constrained.     

长基线中微子振荡几率和CP破坏效应

研究三味中微子在物质中的振荡,从理论上严格解出了绝热近似下在物质中三味中微子的质量平方矩阵本征值和物质中的中微子有效混合矩阵,并计算出三味中微子在长基线实验中的振荡几率和CP破坏效应.     

Signals of CPT violation and non-locality in future neutrino oscillation experiments

We investigate the sensitivities of future neutrino oscillation experiments for measuring the neutrino mass squared differences and leptonic mixing angles independently with neutrinos and anti-neutrinos. We update the expected sensitivities of Neutrino Factories to the “atmospheric” (anti-)neutrino parameters using an optimized setup. A dedicated β-Beam facility, in combination with a SPMIN reactor experiment, could give excellent sensitivities also to the “solar” parameters, for neutrinos and anti-neutrinos respectively. A signal of a different mass matrix for neutrinos and anti-neutrinos would imply CPT violation and non-locality of the underlying particle theory.     

Neutrino mass spectrum from the results of neutrino oscillation experiments

All the possible schemes of neutrino mixing with four massive neutrinos inspired by the existing experimental indications in favor of neutrino mixing are considered in a model independent way. Assuming that in short-baseline experiments only one mass-squared difference is relevant, it is shown that the scheme with a neutrino mass hierarchy is not compatible with the experimental results. Only two schemes with two pairs of neutrinos with close masses separated by a mass difference of the order of 1 eV are in agreement with the results of all experiments. One of these schemes leads to possibly observable effects in³H and (β,β)oν experiments.     

Baryogenesis via Sterile neutrino oscillation and neutrino parameters

We investigate baryogenesis in the νMSM which is the Minimal Standard Model (MSM) extended by three right-handed neutrinos with Majorana masses being smaller than the weak scale. In this model three sterile neutrinos, which are almost right-handed states, play important roles in cosmology. The baryon asymmetry of the universe (BAU) is generated via mechanism through flavor oscillation between two sterile neutrinos N₂ and N₃ which are degenerate in masses. We consider the case when BAU is solely originated from the CP violating phases in the mixing matrix of active neutrinos, i.e., the Dirac phase δ and the Majorana phase η, and study how BAU depends on these CP violating phases.     

Solar neutrino oscillation phenomenology

This article summarises the status of the solar neutrino oscillation phenomenology at the end of 2002 in the light of the SNO and KamLAND results. We first present the allowed areas obtained from global solar analysis and demonstrate the preference of the solar data towards the large-mixing-angle (LMA) MSW solution. A clear confirmation in favour of the LMA solution comes from the KamLAND reactor neutrino data. The KamLAND spectral data in conjunction with the global solar data further narrows down the allowed LMA region and splits it into two allowed zones a low Δm ² region (low-LMA) and high Δm ² region (high-LMA). We demonstrate through a projected analysis that with an exposure of 3 kton-year (kTy) KamLAND can remove this ambiguity.     

Solar neutrino problem and gravitationally induced long-wavelength neutrino oscillation

We have reexamined the possibility of explaining the solar neutrino data through long-wavelength neutrino oscillations induced by a tiny breakdown of the weak equivalence principle of general relativity. We have found that such gravitationally induced oscillations can provide a viable solution to the solar neutrino problem.