1,672 research outputs found
The Rotating Mass Matrix, the Strong CP Problem and Higgs Decay
We investigate a recent solution to the strong CP problem, obtaining a
theta-angle of order unity, and show that a smooth trajectory of the massive
eigenvector of a rank-one rotating mass matrix is consistent with the
experimental data for both fermion masses and mixing angles (except for the
masses of the lightest quarks). Using this trajectory we study Higgs decay and
find suppression of compared to the standard model
predictions for a range of Higgs masses. We also give limits for flavour
violating decays, including a relatively large branching ratio for the
mode.Comment: 15 pages, 6 figures; improvements to introduction and preliminarie
On the Corner Elements of the CKM and PMNS Matrices
Recent experiments show that the top-right corner element () of the
PMNS, like that () of the CKM, matrix is small but nonzero, and suggest
further via unitarity that it is smaller than the bottom-left corner element
(), again as in the CKM case (). An attempt in
explaining these facts would seem an excellent test for any model of the mixing
phenomenon. Here, it is shown that if to the assumption of a universal rank-one
mass matrix, long favoured by phenomenologists, one adds that this matrix
rotates with scale, then it follows that (A) by inputting the mass ratios
, and , (i) the corner elements are
small but nonzero, (ii) , , (iii)
estimates result for the ratios and , and
(B) by inputting further the experimental values of and
, (iv) estimates result for the values of the corner elements
themselves. All the inequalities and estimates obtained are consistent with
present data to within expectation for the approximations made.Comment: 9 pages, 2 figures, updated with new experimental data and more
detail
N-String Vertices in String Field Theory
We give the general form of the vertex corresponding to the interaction of an
arbitrary number of strings. The technique employed relies on the ``comma"
representation of String Field Theory where string fields and interactions are
represented as matrices and operations between them such as multiplication and
trace. The general formulation presented here shows that the interaction vertex
of N strings, for any arbitrary N, is given as a function of particular
combinations of matrices corresponding to the change of representation between
the full string and the half string degrees of freedom.Comment: 22 pages, A4-Latex (latex twice), FTUV IFI
New Angle on the Strong CP and Chiral Symmetry Problems from a Rotating Mass Matrix
It is shown that when the mass matrix changes in orientation (rotates) in
generation space for changing energy scale, then the masses of the lower
generations are not given just by its eigenvalues. In particular, these masses
need not be zero even when the eigenvalues are zero. In that case, the strong
CP problem can be avoided by removing the unwanted term by a chiral
transformation in no contradiction with the nonvanishing quark masses
experimentally observed. Similarly, a rotating mass matrix may shed new light
on the problem of chiral symmetry breaking. That the fermion mass matrix may so
rotate with scale has been suggested before as a possible explanation for
up-down fermion mixing and fermion mass hierarchy, giving results in good
agreement with experiment.Comment: 14 page
Witten's cubic vertex in the comma theory (I)
It is shown that Witten's interaction 3-vertex is a solution to the comma overlap equations; hence establishing the equivalence between the conventional and the 'comma' formulation of interacting string theory at the level of vertices
A Solution of the Strong CP Problem Transforming the theta-angle to the KM CP-violating Phase
It is shown that in the scheme with a rotating fermion mass matrix (i.e. one
with a scale-dependent orientation in generation space) suggested earlier for
explaining fermion mixing and mass hierarchy, the theta-angle term in the QCD
action of topological origin can be eliminated by chiral transformations, while
giving still nonzero masses to all quarks. Instead, the effects of such
transformations get transmitted by the rotation to the CKM matrix as the KM
phase giving, for of order unity, a Jarlskog invariant typically of
order as experimentally observed. Strong and weak CP violations
appear then as just two facets of the same phenomenon.Comment: 14 pages, 2 figure
Chiral corrections to the Gell-Mann-Oakes-Renner relation
The next to leading order chiral corrections to the
Gell-Mann-Oakes-Renner (GMOR) relation are obtained using the pseudoscalar
correlator to five-loop order in perturbative QCD, together with new finite
energy sum rules (FESR) incorporating polynomial, Legendre type, integration
kernels. The purpose of these kernels is to suppress hadronic contributions in
the region where they are least known. This reduces considerably the systematic
uncertainties arising from the lack of direct experimental information on the
hadronic resonance spectral function. Three different methods are used to
compute the FESR contour integral in the complex energy (squared) s-plane, i.e.
Fixed Order Perturbation Theory, Contour Improved Perturbation Theory, and a
fixed renormalization scale scheme. We obtain for the corrections to the GMOR
relation, , the value . This result
is substantially more accurate than previous determinations based on QCD sum
rules; it is also more reliable as it is basically free of systematic
uncertainties. It implies a light quark condensate . As a byproduct, the chiral perturbation theory (unphysical) low energy
constant is predicted to be , or .Comment: A comment about the value of the strong coupling has been added at
the end of Section 4. No change in results or conslusion
Bottom quark mass and QCD duality
The mass of the bottom quark is analyzed in the context of QCD finite energy sum rules. In contrast to the conventional approach, we use a large momentum expansion of the QCD correlator including terms to order alpha(S)(2)(m(b)(2)/q(2))(6) with the upsilon resonances from e(+)c(-) annihilation data as main input. A stable result m(b)(m(b)) = (4.19 +/- 0.05) GeV for the bottom quark mass is obtained. This result agrees with the independent calculations based on the inverse moment analysis
Nucleation and Growth of the Zn-Fe Alloy from a Chloride Electrolyte
In this study, the kinetics of Zn-Fe codeposition was investigated in chloride acidic solution using
cyclic voltammetry. Anomalous codeposition is detected and this mechanism depends on the Zn(II) / Fe(II)
concentration ratio in the electrolytic bath. The study of early stages of electrodeposition showed that Zn-
Fe follows a theoretical response to instantaneous nucleation evolves into a progressive nucleation
according to the model of Scharifker and Hills. The morphology and structure of the coatings is discussed
using characterization techniques. Dense, uniform, and singlephased Zn-Fe coatings could be obtained
with a Zn-Fe ratio of 1/3.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3531
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