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Harald Fritzsch

Publications and source records attributed to Harald Fritzsch.

At least 73 records · Page 4Linked to original sources
arXiv2000

Mass and Flavor Mixing Schemes of Quarks and Leptons

We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass generation could be built, are emphasized. A variety of schemes of quark mass matrices at low and superhigh energy scales are described, and their consequences on flavor mixing and CP violation are discussed. Instructive patterns of lepton mass matrices, which can naturally lead to large flavor mixing angles, are explored to interpret current data on atmospheric and solar neutrino oscillations. We expect that B-meson factories and long-baseline neutrino experiments will soon shed more light on the dynamics of fermion masses, flavor mixing and CP violation.

hep-ph↗
arXiv1999

CP Violation and the Light Quark Sector

In view of the observed strong hierarchy of quark masses, we discuss a new description of flavor mixing which is particularly suited for models of quark mass matrices based on flavor symmetries. The necessary and sufficient conditions for CP violation are clarified. The emergence of CP violation is primarily linked to a large phase difference (near 90^{\circ}) in the light quark sector. The unitarity triangle is determined by the mass ratios of the light quarks. We conclude that the unitarity triangle should be close or identical to a rectangular triangle, and CP violation is maximal in this sense.

hep-ph↗
arXiv1999

Maximal Neutrino Mixing and Maximal CP Violation

We propose a phenomenological model of lepton mixing and CP violation based on the flavor democracy of charge leptons and the mass degeneracy of neutrinos. A nearly bi-maximal flavor mixing pattern, which is favored by current data on atmospheric and solar neutrino oscillations, emerges naturally from this model after explicit symmetry breaking. The rephasing-invariant strength of CP or T violation can be as large as one percent, leading to significant probability asymmetries between ν_μ\to ν_e and \barν_μ\to \barν_e (or ν_e \to ν_μ) transitions in the long-baseline neutrino experiments.

hep-ph↗
arXiv1999

The Light Quark Sector, CP Violation, and the Unitarity Triangle

In view of the observed strong hierarchy of quark masses, we propose a new description of flavor mixing which is particularly suited for models of quark mass matrices based on flavor symmetries. The necessary and sufficient conditions for CP violation are clarified. The emergence of CP violation is primarily linked to a large phase difference (near 90^{\circ}) in the light quark sector. The unitarity triangle is determined by the mass ratios of the light quarks. We conclude that the unitarity triangle should be close or identical to a rectangular triangle, and CP violation is maximal in this sense. Instructive predictions for flavor mixing angles and CP-violating parameters, which can directly be confronted with the forthcoming data from B-meson factories, are obtained from a specific texture of quark mass matrices.

hep-ph↗
arXiv1999

The Production of Single t-Quarks at LEP and HERA

We study the possibility to produce single t-quarks both at LEP II and HERA. While within the Standard Model such reactions are not observable, the possibility exists in a wide class of dynamical models for the fermion mass generation. General arguments, based on hierarchical and democratic symmetries are used to arrive at t-production rates which are detectable.

hep-ph↗
arXiv1999

Nearly Degenerate Neutrino Masses and Nearly Decoupled Neutrino Oscillations

We introduce a simple flavor symmetry breaking scheme, in which charged lepton masses have a strong hierarchy and neutrino masses are almost degenerate. It is possible to obtain a natural suppression of lepton flavor mixing between the 1st and 3rd families as well as the approximate decoupling of atmospheric and solar neutrino oscillations with nearly bi-maximal mixing factors. The similarity and difference between lepton and quark flavor mixing schemes are briefly discussed.

hep-ph↗
arXiv1999

Quark Mass Hierarchies and Maximal CP--Violation

It is argued taking into account the observed mass spectra of the leptons and quarks that the phenomenon of flavor mixing is intimately related to the mass spectra. We discuss a particularly interesting way to describe the flavor mixing which is particularly suited for models of quark mass matrices based on flavor symmetries. CP violated is maximal or class to being maximal in our approach.

hep-ph↗
arXiv1998

Large Leptonic Flavor Mixing and the Mass Spectrum of Leptons

Implications of a simple model for the mass generation of leptons are studied, in particular for the upcoming long-baseline neutrino experiments. The flavor mixing angles are large (nearly maximal). The probability for the long-baseline ν_μ\leftrightarrow ν_e oscillation is predicted to be about 1%.

hep-ph↗
arXiv1998

Mass Hierarchies, Hidden Symmetry and Maximal CP-Violation

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into account. One particular interesting way to describe the flavor mixing, which, however, is not the one used today, emerges, which is particularly suited for models of quark mass matrices based on flavor symmetries. We conclude that the unitarity triangle important for B physics should be close to or identical to a rectangular triangle. CP violation is maximal in this sense.

hep-ph↗
arXiv1998

The Mixing of Quarks and Leptons and Neutrino Degeneracy

In drawing on an analogy with the flavor mixing observed in the quark sector we discuss a pattern of large flavor mixing angles in the lepton sector. Simple arguments based on a democratic symmetry and its violation in the lepton sector allow us to determine the flavor mixing matrix of leptons. The mixing angle relevant for solar neutrino oscillations is maximal (close to $45^{\circ}$), while the angle relevant for atmospheric neutrino oscillations is given by $\sin^2 2 θ= 8/9$. The emerging pattern is consistent with the results of the solar and atmospheric neutrino experiments.

hep-ph↗
arXiv1998

Quark Mass Hierarchies, Flavor Mixing and Maximal CP-Violation

Flavor mixing and the quark mass spectrum are intimately related. In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into account. One particular interesting way to describe the flavor mixing emerges, which is particularly suited for models of quark mass matrices based on flavor symmetries. We conclude that the unitarity triangle important for $B$ physics should be close to or identical to a rectangular triangle. $CP$ violation is maximal in this sense.

hep-ph↗
arXiv1998

Quark Mass Hierarchy and Flavor Mixing

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles it is argued that the description of flavor mixing must take this into account. One particular interesting way to describe the flavor mixing, which, however, is not the one used today, emerges, which is best suited for models of quark mass matrices based on flavor symmetries. We conclude that the unitarity triangle important for $B$ physics should be close to or identical to a rectangular triangle. CP violation is maximal in this sense.

hep-ph↗
arXiv1997

The Kinematics and Dynamics of Flavor Mixing

In view of the observed strong hierarchy of the quark and lepton masses and of the flavor mixing angles, it is argued that the description of flavor mixing must take this into account. One particularly interesting way to describe the flavor mixing, which, however, is not the one used today, emerges, which is particularly suited for models of quark mass matrices based on flavor symmetries. We conclude that the unitarity triangle important for B physics should be close to or identical to a rectangular triangle. CP violation is maximal in this sense.

hep-ph↗
arXiv1997

The Gluonic Decay of the $b$--Quark and tne $η'$--Meson

The observed inclusive decay of B-mesons into eta' + X is interpreted as the consequence of the gluonic decay of the b-quark into an s-quark. As a result of the QCD anomaly this decay proceeds partly as the decay b ---> s + eta', similar to b ---> s + J/psi. The hadronic recoiling system is found to have a relatively large mass. Analogously one expects a decay of the type b ---> s + sigma. The branching ratios for these decays are large (of the order of 10%). The results indicate that there is no room for an anomalously large chromomagnetic decay mode of the b-quark. Gluon jets are expected to exhibit an anomalously large tendency to fragment into eta'- and sigma-mesons.

hep-ph↗
arXiv1997

Flavor Mixing, CP-Violation and the Masses ov the Light Quarks

The observed hierarchy of the quark masses is interpreted as a signal for an underlying ``subnuclear democracy'' as the relevant symmetry of the quark mass terms. A simple breaking of the symmetry leads to a mixing between the second and the third family, in agreement with observation. Introducing the mixing between the first and the second family, one finds an interesting pattern of maximal CP--violation as well as a complete determination of the elements of the CKM matrix and of the unitarity triangle.

hep-ph↗
arXiv1997

Flavor Mixing and the Masses of Quarks and Leptons

A simple breaking of the subnuclear democracy of the quarks leads to a mixing between the second and the third family, in agrement with observation. Introducing the mixing between the first and the second family, one finds an interesting pattern of maximal CP--violation as well as a complete determination of the elements of the CKM matrix and of the unitarity triangle.

hep-ph↗
arXiv1997

The Symmetry and the Problem of Mass Generation

The mass problem in particle physics and its impact for other fields is discussed. While the problem of the nuclear masses has been resolved within the QCD framework, many parameters of the ``Standard Model'' are related to the fermion sector. The origin of the fermion masses remains unresolved. We discuss attempts to explain the observed hierarchical features of the mass spectrum by a symmetry, relating the mass eigenvalues to the flavor mixing angles.

hep-ph↗