Predicting lepton flavor mixing from Δ(48) and generalized C P symmetries

We propose to understand the mixing angles and C P-violating phases from the ?(48) family symmetry combined with the generalized C P symmetry. A model-independent analysis is performed by scanning all the possible symmetry breaking chains. We find a new mixing pattern with only one free parameter, excellent agreement with the observed mixing angles can be achieved and all the C P-violating phases are predicted to take nontrivial values. This mixing pattern is testable in the near future neutrino oscillation and neutrinoless double-beta decay experiments.Finally, a flavor model is constructed to realize this mixing pattern.     

Mini-review of rare charmonium decays at BESⅢ

Recently, the LHCb experiment announced 3.5σ evidence for direct CP violation in D⁰ decay by looking at the difference between A_CP(D⁰→K⁺K^-) and A_CP(D⁰→π⁺π^-). This is the rst evidence of CP violation in a charm system, which may indicate new physics beyond the Standard Model. Motivated by this measurement, we review rare processes in charmonium decay, especially, the weak decay, C or P violated decay, and lepton avor violated decays. In case the new physics appears in charm sector, these rare decays of charmonium states will provide an opportunity to search for signi cant contributions from physics beyond the Standard Model. With huge J/ψ and ψ(2S) samples in BES0 experiment, the rare decays may be feasible.     

Multiscalar B-L extension based on S4flavor symmetry for neutrino masses and mixing

A multiscalar and nonrenormalizable B-L extension of the standard model(SM)with S₄symmetry which successfully explains the recently observed neutrino oscillation data is proposed.The tiny neutrino masses and their hierarchies are generated via the type-I seesaw mechanism.The model reproduces the recent experiments of neutrino mixing angles and Dirac CP violating phase in which the atmospheric angle(θ₂₃)and the reactor angle(θ₁₃)get the best-fit values while the solar angle(θ₁₂)and Dirac CP violating phase(δ)are in 3σrange of the best-fit value for the normal hierarchy(NH).For the inverted hierarchy(IH),θ13 gets the best-ft value andθ₂₃together withδare in the lσrange,whileθ12 is in 3δrange of the best-fit value.The effective neutrino masses are pre-dicted to be(m_ee)=6.81 meV for the NH and(m_ee)=48.48 meV for the IH,in good agreement with the most re-cent experimental data.     

Histogram comparison used in BESⅢ software and data validation

The performance of histogram comparison is studied for the various types of hypothesis test methods. The Kolmogorov test is recommended for the software and data validation and the minimum event numbers for different distributions are given in order to get more reliable results. A new bin content comparison method is implemented to deal with the hitmap-like histograms.     

The ■ tetraquark states and the structure of X(2239) observed by the BESⅢ collaboration

We investigate the mass spectrum of the■tetraquark states in the relativized quark model.By solving the Schrodinger-like equation with the relativized potential,the masses of S-and P-wave■tetraquarks are obtained.The screening effects are also taken into account.It is found that the resonant structureX(2239)observed in thee+e-→K+K-process by the BESIII collaboration can be assigned as a P-wave 1--■tetraquark state.Furthermore,the radiative transition and the strong decay behavior of this structure are also estimated,which can provide helpful information for future experimental searches.     

Measurement of the integrated luminosities of the data taken by BESⅢ at √s=3.650 and 3.773 GeV

Data sets were collected with the BESⅢ detector at the BEPCⅡ collider at the center-of-mass energy of √s=3.650 GeV during May 2009 and at √s=3.773 GeV from January 2010 to May 2011. By analyzing the large angle Bhabha scattering events, the integrated luminosities of the two data sets are measured to be （44.49±0.02±0.44） pb-1 and （2916.94±0.18±29.17） pb-1, respectively, where the first error is statistical and the second error is systematic.     

Searching for new physics in D^0→μ^＋ μ^-,e^＋e^-,μ^±e at BES and/or the super charm-tau factory

In contrast with B0-ˉB0, Bs-ˉBs mixing where the standard model（SM） contributions overwhelm that of the new physics beyond standard model（BSM）, a measured relatively large D0-ˉD0mixing where the SM contribution is negligible, definitely implies the existence of the new physics BSM. It is natural to consider that the rare decays of D meson might be more sensitive to new physics, and the decay mode D0→μ＋μ-could be an ideal area to search for new physics because it is a flavor changing process. In this work we look for a trace of the new physics BSM in the leptonic decays of D0. Concretely we discuss the contributions of unparticle or an extra gauge boson Z while imposing the constraints set by fitting the D0-ˉD0mixing data. We find that the long-distance SM effects for D0→lˉl still exceed those contributions of the BSM under consideration, but for a double-flavor changing process such as D0→μ±e, the new physics contribution would be significant.     

Searching for new physics in D0→μ+μ-, e+e-,μ±e干 at BES and/or the super charm-tau factory

In contrast with B⁰-B⁰, B_s-B_s mixing where the standard model (SM) contributions overwhelm that of the new physics beyond standard model (BSM), a measured relatively large D⁰-D⁰ mixing where the SM contribution is negligible, definitely implies the existence of the new physics BSM. It is natural to consider that the rare decays of D meson might be more sensitive to new physics, and the decay mode D⁰→μ⁺μ^- could be an ideal area to search for new physics because it is a flavor changing process. In this work we look for a trace of the new physics BSM in the leptonic decays of D⁰. Concretely we discuss the contributions of unparticle or an extra gauge boson Z' while imposing the constraints set by fitting the D⁰- D⁰ mixing data. We find that the long-distance SM effects for D⁰→l1 still exceed those contributions of the BSM under consideration, but for a double-flavor changing process such as D⁰→μ^±e⁺, the new physics contribution would be significant.