Neutrino Magnetic Moments and Minimal Supersymmetric SO(10) Model

We examine supersymmetric contributions to transition magnetic moments of Majorana neutrinos. We first give the general formula for it. In concrete evaluations, informations of neutrino mass matrix elements including CP phases are necessary. Using unambiguously determined neutrino mass matrices in recently proposed minimal supersymmetric SO(10) model, the transition magnetic moments are calculated. The resultant neutrino magnetic moments are found to be roughly an order of magnitude larger than those calculated in the standard model extended to incorporate the see-saw mechanism.Comment: 8 pages, 4 figures, the version to be published in International Journal of Modern Physics

A comprehensive study of neutrino spin-flavour conversion in supernovae and the neutrino mass hierarchy

Resonant spin-flavour (RSF) conversions of supernova neutrinos, which is induced by the interaction between the nonzero neutrino magnetic moment and supernova magnetic fields, are studied for both normal and inverted mass hierarchy. As the case for the pure matter-induced neutrino oscillation (Mikheyev--Smirnov--Wolfenstein (MSW) effect), we find that the RSF transitions are strongly dependent on the neutrino mass hierarchy as well as the value of $\theta_{13}$. Flavour conversions are solved numerically for various neutrino parameter sets, with presupernova profile calculated by Woosley and Weaver. In particular, it is very interesting that the RSF-induced \nu_\rme\to\bar\nu_\rme transition occurs, if the following conditions are all satisfied: the value of $\mu_\nu B$ ($\mu_\nu$ is the neutrino magnetic moment, and $B$ is the magnetic field strength) is sufficiently strong, the neutrino mass hierarchy is inverted, and the value of $\theta_{13}$ is large enough to induce adiabatic MSW resonance. In this case, the strong peak due to original \nu_\rme emitted from neutronization burst would exist in time profile of the neutrino events detected at the Super-Kamiokande detector. If this peak were observed in reality, it would provide fruitful information on the neutrino properties. On the other hand, characters of the neutrino spectra are also different between the neutrino models, but we find that there remains degeneracy among several models. Dependence on presupernova models is also discussed.Comment: 23 pages, 11 figures, corrected minor typos, added references. Final version to appear in Journal of Cosmology and Astroparticle Physic

The solution to a multichannel Bethe potential and its application to pion-nucleus reactions

We solve a radial Schr\"odinger equation for the case of a multichannel square well plus an exponential potential in one of the channels. The solution is obtained by summing exactly the infinite terms of the perturbative series for the evolution operator of the system. Analytical expressions for the scattering matrix and the scattering length are given, a Deser-like formula which connects approximate ground energies and scattering length is obtained for a particular case. Possible physical applications of these results are discussed briefly.Comment: Title changed and other minor changes. 14pages, latex, no figure

Two Gallium data sets, spin flavour precession and KamLAND

We reexamine the possibility of a time modulation of the low energy solar neutrino flux which is suggested by the average decrease of the Ga data in line with our previous arguments. We perform two separate fits to the solar neutrino data, one corresponding to 'high' and the other to 'low' Ga data, associated with low and high solar activity respectively. We therefore consider an alternative to the conventional solar+KamLAND fitting, which allows one to explore the much wider range of the $\theta_{12}$ angle permitted by the KamLAND fitting alone. We find a solution with parameters $\Delta m^2_{21}=8.2\times 10^{-5} eV^2, tan^{2}\theta=0.31$ in which the 'high' and the 'low' Ga rates lie far apart and are close to their central values and is of comparable quality to the global best fit, where these rates lie much closer to each other. This is an indication that the best fit in which all solar and KamLAND data are used is not a good measure of the separation of the two Ga data sets, as the information from the low energy neutrino modulation is dissimulated in the wealth of data. Furthermore for the parameter set proposed one obtains an equally good fit to the KamLAND energy spectrum and an even better fit than the 'conventional' LMA one for the reactor antineutrino survival probability as measured by KamLAND.Comment: V2: 15 pages, 3 eps figures, fit improved, final version to appear in Journal of Physics

The Omega Effect as a Discriminant for Space-Time Foam

If there is CPT violation, the nature of entanglement for neutral meson pairs produced in meson factories may, on general grounds, be affected. The new form of entanglement is the omega effect. Gravitational decoherence, due to space-time foam, may be one route for deviations from CPT invariance. Two models of space-time foam are considered. One, based on non-critical string theory, is able to produce the new correlations in a natural way. The other, based on the paradigm of thermal-like baths, is shown to be surprisingly resistant to producing the effect even on exercising a total freedom of choice for the state of the bathComment: 10 pages, 1 figure, Invited talk at 5th International Symposium on Quantum Theory and Symmetries, Valladolid, Spain, July 200

Increased fidelity of protein synthesis extends lifespan

Loss of proteostasis is a fundamental process driving aging. Proteostasis is affected by the accuracy of translation, yet the physiological consequence of having fewer protein synthesis errors during multi-cellular organismal aging is poorly understood. Our phylogenetic analysis of RPS23, a key protein in the ribosomal decoding center, uncovered a lysine residue almost universally conserved across all domains of life, which is replaced by an arginine in a small number of hyperthermophilic archaea. When introduced into eukaryotic RPS23 homologs, this mutation leads to accurate translation, as well as heat shock resistance and longer life, in yeast, worms, and flies. Furthermore, we show that anti-aging drugs such as rapamycin, Torin1, and trametinib reduce translation errors, and that rapamycin extends further organismal longevity in RPS23 hyperaccuracy mutants. This implies a unified mode of action for diverse pharmacological anti-aging therapies. These findings pave the way for identifying novel translation accuracy interventions to improve aging

High-Dimensional Feature Selection by Feature-Wise Kernelized Lasso

The goal of supervised feature selection is to find a subset of input features that are responsible for predicting output values. The least absolute shrinkage and selection operator (Lasso) allows computationally efficient feature selection based on linear dependency between input features and output values. In this paper, we consider a feature-wise kernelized Lasso for capturing non-linear input-output dependency. We first show that, with particular choices of kernel functions, non-redundant features with strong statistical dependence on output values can be found in terms of kernel-based independence measures. We then show that the globally optimal solution can be efficiently computed; this makes the approach scalable to high-dimensional problems. The effectiveness of the proposed method is demonstrated through feature selection experiments with thousands of features.Comment: 18 page

Solar Mikheyev-Smirnov-Wolfenstein Effect with Three Generations of Neutrinos

Under the assumption that the density variation of the electrons can be approximated by an exponential function, the solar Mikheyev-Smirnov-Wolfenstein effect is treated for three generations of neutrinos. The generalized hypergeometric functions that result from the exact solution of this problem are studied in detail, and a method for their numerical evaluation is presented. This analysis plays a central role in the determination of neutrino masses, not only the differences of their squares, under the assumption of universal quark-lepton mixing.Comment: 22 pages, LaTeX, including 2 figure