116955892
Realisability of SUSY discrete flavour symmetry in our universe
We study the realisation of supersymmetric discrete flavour symmetry models to the thermal history of our universe. We focus on the evolution of the pseudo moduli field among the flavons by taking into account finite temperature corrections. We show that the pseudo moduli flavon dominates the energy density of our universe and this domination makes crucially difficult to realise the flavour symmetry models in our universe. We also discuss possible extensions of the supersymmetric discrete flavour symmetry models which can ensure the consistency of the models with the thermal history of our universe. Finally, we show an extension to realise the thermal inflation by the flavon domination.
9783573
S4 Flavor Symmetry of Quarks and Leptons in SU(5) GUT
We present an S4 flavor model to unify quarks and leptons in the framework of the SU(5) GUT. Three generations of 5-plets in SU(5) are assigned to 31 of S4, while the first and second generations of 10-plets in SU(5) are assigned to 2 of S4, and the third generation of 10-plets is assigned to 11 of S4. Right-handed neutrinos are also assigned to 2 for the first and second generations and to 11 for the third generation. By considering the vacuum alignments of relevant gauge singlet scalars, we predict the quark mixing as well as the tribimaximal mixing of neutrino flavors. In particular, the Cabbibo angle is predicted to be 15 ◦ in the limit of the vacuum alignment. We can improve the model to predict observed CKM mixing angles as well as the nonvanishing Ue3 of the neutrino flavor mixing. Subject Index: 140, 154
453979
S4 Flavor Model of Quarks and Leptons
We present an S4 flavor model to unify quarks and leptons in the framework of the SU(5) GUT. Three generations of 5-plets in SU(5) are assigned to be 31 of S4 while the first and the second generations of 10-plets in SU(5) are assigned to be 2 of S4 ,a nd the third generation of 10-plet is to be 11 of S4. Right-handed neutrinos are also assigned to be 2 for the first and second generations and 11 for the third generation, respectively. Taking vacuum alignments of relevant gauge singlet scalars, we predict the quark mixing as well as the tri-bimaximal mixing of neutrino flavors. Especially, the Cabbibo angle is predicted to be 15 ◦ in the limit of the vacuum alignment. We can improve the model to predict observed CKM mixing angles.
118806271
Supersymmetry contributions to CP violations in b→s and b→d transitions taking account of new data
We study the contribution of the gluino-squark mediated flavor changing process for the CP violation in $b\to s$ and $b\to d$ transitions facing on recent experimental data. The mass insertion parameters of squarks are constrained by the branching ratios of $b\to s\gamma $ and $b\to d\gamma $ decays. In addition, the time dependent CP asymmetries of $B^0\to \phi K_S$ and $B^0\to \eta ' K^0$ decays severely restrict the allowed region of the mass insertion parameter for the $b\to s$ transition. By using these constraints with squark and gluino masses of 1.5 TeV, we predict the CP asymmetries of $B_s\to \phi \phi $, $B_s\to \eta '\phi $, and $B^0\to K^0\bar K^0$ decays, as well as the CP asymmetries in $b\to s\gamma $ and $b\to d\gamma $ decays. The CP violation in the $B_s\to \phi \phi$ decay is expected to be large owing to the squark flavor mixing, which will be tested at LHCb soon.
120533600
An Introduction to Non-Abelian Discrete Symmetries for Particle Physicists
Introduction.- Basics of Finite Groups.- Subgroups and Decompositions of Multiplets.- Anomalies.- Non-Abelian Discrete Symmetry in Quark/Lepton Flavor Models.- Useful Theorems.- Representations of S4 in Different Bases.- Representations of A4 in Different Bases.- Representations of A5 in Different Bases.- Representations of T1 in Different Bases.- Other Smaller Groups.- References.
118837490
Minimal neutrino texture with neutrino mass ratio and Cabibbo angle
We present neutrino mass matrix textures in a minimal framework of the type-I seesaw mechanism, where two right-handed Majorana neutrinos are introduced in order to reproduce experimental results of neutrino oscillations. The textures can lead to experimentally favored leptonic mixing angles described by tri-bimaximal mixing with one additional rotation. We present minimal and next to minimal textures for the normal mass hierarchy case in the context of the texture zero. A minimal texture in the inverted hierarchy case is also constructed, which does not have any vanishing entries in a Dirac neutrino mass matrix. We also discuss some cases in which the model parameters in the textures are supposed to be a neutrino mass ratio and/or the Cabibbo angle. Predicted regions of mixing angles, a leptonic CP-violation parameter, and an effective mass for the neutrinoless double beta decay are presented in all textures.
122914730
Computation of loop integrals using extrapolation
We present a class of methods for the evaluation of loop integrals based on extrapolation. The method is based on generating a sequence of approximations which converge to the loop integral value as a parameter e introduced in the integrand tends to zero. We examine the applicability of linear and non-linear extrapolation processes. Test results are given for one-loop three-point vertex and four-point functions and for a two-loop vertex diagram.
55566134
Current status of the LHCf experiment and future plan
The Large Hadron Collider forward (= LHCf) experiment has successfully finished the first phase of data taking at LHC √ s = 0.9 and 7 TeV proton-proton collisions in 2010. As current status, we concentrate on analyzing the obtained data. As the first result, the energy spectra of photon measured by LHCf during = 7 TeV p-p collision has been published recently. Also the study of the upgraded version of LHCf detector for future = 14TeV run scenario is developed with the GSO scintillator. Another possible plan of p-A(nuclear) collision in LHC is also studied. In this paper, as the current status of the experiment, analyses, and works for foreseen detector upgrade are summarized.
55415432
Forward physics with the LHCf experiment: a LHC contribution to cosmic-ray physics
LHCf is a small detector installed at LHC accelerator to measure neutral par- ticle flow in the forward direction of proton - proton (p - p) and proton - nucleus (p - A) interactions. Thanks to the optimal performance that has characterized the last years' running of the LHC collider, several measurements have been taken since 2009 in differ- ent running conditions. After data taking for p - p interactions at √ s = 900 GeV, 2.76 TeV and 7 TeV and proton - Lead nucleus (p - Pb) at √ sNN = 5.02 TeV (energy of a couple of projectile and target nucleons in their center of mass reference frame), LHCf is now going to complete its physics program with the 13 TeV p - p run foreseen in 2015. The com- plete set of results will become a reference data set of forward physics for the calibration and tuning of the hadronic interaction models currently used for the simulation of the atmospheric showers induced by very high energy cosmic rays. For this reason we think that LHCf is giving an important contribution for the study of cosmic rays at the highest energies. In this paper the experiment, the published results and the current status are reviewed.
1235737
Radioactive ion beam transportation for the fundamental symmetry study with laser-trapped atoms.
The search for the violation of the fundamental symmetry in a radioactive atom is the promising candidate for precision tests of the standard model and its possible extensions. The subtle signal arising from the symmetry violation is enhanced in heavy atoms, such as a francium (Fr). To realize high precision measurements, a large amount of radioactive isotopes is required. The Fr is produced via a nuclear fusion reaction using a melted gold target with a (18)O primary beam at Cyclotron and Radioisotope Center, Tohoku University. The maximum extraction efficiency of the Fr ion was achieved at approximately 35%. The beam line consists of an electrostatic deflector, three electrostatic quadrupole triplets to the measurement area at 10 m away from the reaction point, and several beam diagnosis systems. We optimized parameters of the beam line.
56001873
Complete Set of Deuteron Analyzing Powers for dp Elastic Scattering at Intermediate Energies and Three Nucleon Forces
With the aim of clarifying roles of the 3NFs in nuclei experimental programs with the polarized deuteron beam at intermediate energies are in progress at RIKEN RI Beam Factory. As the first step, we have measured a complete set of deuteron analyzing powers in deuteron–proton elastic scattering at 250 and 294 MeV/nucleon. The obtained data are compared with the Faddeev calculations based on the modern nucleon–nucleon forces together with the Tucson–Melbourne’99, and UrbanaIX three nucleon forces.