448 research outputs found
Canonical Constraints on Leptonic Cp Violation using UHCR neutrino fluxes
It is shown that one can in principle constrain the CP-violating parameter
delta from measurements of four independant |V_{ij}|^2, or three of them and a
ratio, in the leptonic sector. To quantify our approach, using unitarity, we
derive simple expressions in terms of four independant |V_{ij}|^2 for
cos(delta) and an expression for sin^2(delta) from J^2. Thus, depending on the
values of |V_{ij}| and their accuracy, we can set meaningful limits on |delta|.
To illustrate numerically, if |V_{u1}|^2 is close to 0.1 with a 10% precision,
and if |V_{e3}^2 is larger than 0.005 and for values of |V_{e2}|^2 and
|V_{u3}|^2 that stay within +-0.1 of the current experimental data leads to a
bound pi/2 < |delta| < pi. Alternatively, a certain combination of parameters
with values of |V_{e3}|^2 larger than 0.01 leads to a closed bound of 73 <
|delta| < 103. In general, we find that it is better to use |V_{u1}|^2 or
|V_{t1}|^2 as the fourth independant |V_{ij}|^2 and that over most of the
parameter space, delta is least sensitive to |V_{e3}|^2. With just three
independant measurements (solar, atmospheric and reactor) it is impossible to
set limits on the CP phase. In this respect, we study the use of ultra high
energy cosmic (UHCR) neutrino fluxes as the additional fourth information. We
find that within the SM, neutrino fluxes of all three flavours will be very
similar but that pushing current neutrino data to their extreme values still
allowed, ratios of cosmic neutrino fluxes can differ by up to 20%; such large
discrepancies could imply negligibly small CP-violation. We also study a non
radiative neutrino decay model and find that the neutrino fluxes can differ by
a factor of up to 3 within this model and that an accuracy of 10% on the
neutrino fluxes is sufficient to set interestin limits on delta.Comment: 8 pages, 2 figures, 5 table
Neutrino Mixing and Leptogenesis in Symmetry
We study the consequences of the -symmetry behind the --
universality in neutrino mass matrix. We then implement this symmetry in the
type-I seesaw mechanism and show how it can accommodate all sorts of lepton
mass hierarchies and generate enough lepton asymmetry to interpret the observed
baryon asymmetry in the universe. We also show how a specific form of a
high-scale perturbation is kept when translated via the seesaw into the low
scale domain, where it can accommodate the neutrino mixing data. We finally
present a realization of the high scale perturbed texture through addition of
matter and extra exact symmetries.Comment: 29 pages, 1 figure, 3 tables. Complete re-analysis. Version to appear
in PR
Patterns in the Fermion Mixing Matrix, a bottom-up approach
We first obtain the most general and compact parametrization of the unitary
transformation diagonalizing any 3 by 3 hermitian matrix H, as a function of
its elements and eigenvalues. We then study a special class of fermion mass
matrices, defined by the requirement that all of the diagonalizing unitary
matrices (in the up, down, charged lepton and neutrino sectors) contain at
least one mixing angle much smaller than the other two. Our new parametrization
allows us to quickly extract information on the patterns and predictions
emerging from this scheme. In particular we find that the phase difference
between two elements of the two mass matrices (of the sector in question)
controls the generic size of one of the observable fermion mixing angles: i.e.
just fixing that particular phase difference will "predict" the generic value
of one of the mixing angles, irrespective of the value of anything else.Comment: 29 pages, 3 figures, references added, to appear in PR
A â3Pâ soft power model: an agile approach to diplomatic strategy
Soft power is the ability to shape the preferences of others through appeal and attraction rather than coerce using hard power. Today, most countries are embracing the notion of soft power. Managing soft power resources at the disposal of governments and deploying them effectively is critical for an agile government to build an attractive country image, and thereby enhancing their competitiveness in todayâs dynamic and competitive global landscape. This includes but not limited to promoting their countryâs products and services globally, attract foreign investors, and promoting international tourism. In this study, we develop and validate a novel â3Pâ soft power model, using the perceptions about a countryâs âproductsâ, âplacesâ, and âpeopleâ. Using 167 usable responses obtained from a structured country-wide survey in the UAE, the 3P model developed from the literature was tested for reliability, validity, and model-fitness. While Cronbachâs alpha values confirmed the reliability of first-order constructs (products, place and people), the second-order confirmatory factor analysis (CFA) established the convergent and discriminant validity of the constructs, and operationalization of â3P Soft Powerâ as a higher (second)-order model. The results have implications for governments and researchers in promoting soft power by leveraging its products, places and people. A robust higher-order factor model for soft power using 3Pâs has not been developed previously and constitutes the novelty of this study
Pulmonary Embolism Revealing Idiopathic Membranous Glomerulonephritis
We describe a case of a 55-year-old man who presented with pulmonary embolism and who was found to have nephrotic syndrome due to idiopathic membranous nephropathy. There are no other signs of nephrotic syndrome such as edema
Modeling and Optimization of Phosphate Recovery from Industrial Wastewater and Precipitation of Solid Fertilizer using Experimental Design Methodology
In this work, the experimental design methodology is applied to optimize phosphate salts precipitation as struvite and others applied in soil fertilization from treated industrial wastewater stream. This is a process to maximize phosphate recovery percentage from inlet wastewater stream containing interfering foreign ions. Therefore, these optimized conditions could be used as input data for engineering design-software for successive equipment required in wastewater treatment plant. A four factors BoxâBehnken experimental design was used to model and optimize the operating parameters. The optimum
operating conditions were quite efficient in trapping 86.10 % recovered phosphates in industrial stream, and 92.6 % in synthetic solution at pH of 10.89, time of reaction of 34.76 min, temperature of 25.23 °C and R of 2.25 with an insignificance effect for molar ratio (R) between Mg and PO4 ions. If these optimal parameters were shifted, the reached recovery percentage would decrease with the precipitated struvite. The precipitated salts were subjected to characterization through different chemical techniques confirming the presence of struvite with schertelite as a mixed slow release fertilizer
Uplifted supersymmetric Higgs region
We show that the parameter space of the Minimal Supersymmetric Standard Model
includes a region where the down-type fermion masses are generated by the
loop-induced couplings to the up-type Higgs doublet. In this region the
down-type Higgs doublet does not acquire a vacuum expectation value at tree
level, and has sizable couplings in the superpotential to the tau leptons and
bottom quarks. Besides a light standard-like Higgs boson, the Higgs spectrum
includes the nearly degenerate states of a heavy spin-0 doublet which can be
produced through their couplings to the quark and decay predominantly into
\tau^+\tau^- or \tau\nu.Comment: 14 pages; Signs in Eqns. (3.1) and (4.2) corrected, appendix include
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