1,749 research outputs found
Neutrino Mixing Predictions of a Minimal SO(10) Model with Suppressed Proton Decay
During the past year, a minimal renormalizable supersymmetric SO(10) model
has been proposed with the following properties: it predicts a naturally stable
dark matter and neutrino mixing angles theta_atm and theta_13 while at the same
time accommodating CKM CP violation among quarks with no SUSY CP problem.
Suppression of proton decay for all allowed values of tan beta strongly
restricts the flavor structure of the model making it predictive for other
processes as well. We discuss the following predictions of the model in this
paper, e.g. down-type quark masses, and neutrino oscillation parameters, U_e3,
delta_MNSP, which will be tested by long baseline experiments such as T2K and
subsequent experiments using the neutrino beam from JPARC. We also calculate
lepton flavor violation and the lepton asymmetry of the Universe in this model.Comment: 22 pages, 11 figure
Suppressing Proton Decay in the Minimal SO(10) Model
We show that in a class of minimal supersymmetric SO(10) models which have
been found to be quite successful in predicting neutrino mixings, all proton
decay modes can be suppressed by a particular choice of Yukawa textures. This
suppression works for contributions from both left and right operators for
nucleon decay and for arbitrary \tan\beta. The required texture not only fits
all lepton and quark masses as well as CKM parameters but it also predicts
neutrino mixing parameter U_e3 and Dirac CP phase \sin|\delta_MNS| to be
0.07-0.09 and 0.3-0.7 respectively. We also discuss the relation between the
GUT symmetry breaking parameters for the origin of these textures.Comment: 7 pages, 2 figure
A Mathematical Study of the One-Dimensional Keller and Rubinov Model for Liesegang Bands
Our purpose is to start understanding from a mathematical viewpoint experiments in which regularized structures with spatially distinct bands or rings of precipitated material are exhibited, with clearly visible scaling properties. Such patterns are known as Liesegang bands or rings. In this paper, we study a one-dimensional version of the Keller and Rubinow model and present conditions ensuring the existence of Liesegang bands
Statistical mechanics of lossy compression for non-monotonic multilayer perceptrons
A lossy data compression scheme for uniformly biased Boolean messages is
investigated via statistical mechanics techniques. We utilize tree-like
committee machine (committee tree) and tree-like parity machine (parity tree)
whose transfer functions are non-monotonic. The scheme performance at the
infinite code length limit is analyzed using the replica method. Both committee
and parity treelike networks are shown to saturate the Shannon bound. The AT
stability of the Replica Symmetric solution is analyzed, and the tuning of the
non-monotonic transfer function is also discussed.Comment: 29 pages, 7 figure
Statistical mechanics of clonal expansion in lymphocyte networks modelled with slow and fast variables
We study the Langevin dynamics of the adaptive immune system, modelled by a
lymphocyte network in which the B cells are interacting with the T cells and
antigen. We assume that B clones and T clones are evolving in different thermal
noise environments and on different timescales. We derive stationary
distributions and use statistical mechanics to study clonal expansion of B
clones in this model when the B and T clone sizes are assumed to be the slow
and fast variables respectively and vice versa. We derive distributions of B
clone sizes and use general properties of ferromagnetic systems to predict
characteristics of these distributions, such as the average B cell
concentration, in some regimes where T cells can be modelled as binary
variables. This analysis is independent of network topologies and its results
are qualitatively consistent with experimental observations. In order to obtain
full distributions we assume that the network topologies are random and locally
equivalent to trees. The latter allows us to employ the Bethe-Peierls approach
and to develop a theoretical framework which can be used to predict the
distributions of B clone sizes. As an example we use this theory to compute
distributions for the models of immune system defined on random regular
networks.Comment: A more recent version (accepted for publication in Journal of Physics
A: Mathematical and Theoretical) with improved figures, references, et
Temperature dependent Eu 3d-4f X-ray Absorption and Resonant Photoemission Study of the Valence Transition in
We study the mixed valence transition ( 80 K) in
EuNi(SiGe) using Eu 3 X-ray absorption
spectroscopy (XAS) and resonant photoemission spectroscopy (RESPES). The
Eu and Eu main peaks show a giant resonance and the spectral
features match very well with atomic multiplet calculations. The spectra show
dramatic temperature ()-dependent changes over large energies (10 eV)
in RESPES and XAS. The observed non-integral mean valencies of 2.35
0.03 ( = 120 K) and 2.70 0.03 ( = 40 K) indicate homogeneous
mixed valence above and below . The redistribution between
Eu+ and Eu+ states is attributed to
a hybridization change coupled to a Kondo-like volume collapse.Comment: 4 pages, 3 figure
Self-Propelled Aero-GaN Based Liquid Marbles Exhibiting Pulsed Rotation on the Water Surface
We report on self-propelled rotating liquid marbles fabricated using droplets of alcoholic solution encapsulated in hollow microtetrapods of GaN with hydrophilic free ends of their arms and hydrophobic lateral walls. Apart from stationary rotation, elongated-spheroid-like liquid marbles were found, for the first time, to exhibit pulsed rotation on water surfaces characterized by a threshold speed of rotation, which increased with the weight of the liquid marble while the frequency of pulses proved to decrease. To throw light upon the unusual behavior of the developed self-propelled liquid marbles, we propose a model which takes into account skimming of the liquid marbles over the water surface similar to that inherent to flying water lily beetle and the so-called helicopter effect, causing a liquid marble to rise above the level of the water surface when rotating
Proton decay and μ → e + γ connection in a renormalizable SO(10) GUT for neutrinos
Supersymmetric SO(10) grand unified models with renormalizable Yukawa
couplings involving {\bf 10}, {\bf 126} and {\bf 120} Higgs fields have been
shown to give a very economical theory for understanding quark-lepton flavor in
a unified framework. In previous papers, we showed how nucleon decay can be
suppressed in these models without invoking cancellation, by choice of Yukawa
flavor texture within a type II seesaw framework for neutrinos that explains
all mixings and masses including the recently observed "large" .
In this follow-up paper, we extend our earlier work to the case of type I
seesaw and show that the recently measured "large" can be
accommodated in this case while suppressing proton decay. We then point out
that the two cases (type I and II) lead to different testable predictions for
and as well as different
flavor final states in nucleon decay. In particular, we find that for the type
I seesaw case, can be observable while at the same
time suppressing , whereas in the type II seesaw case,
is always suppressed whereas is
observable.Comment: 27 pages, 2 figure
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