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in subjects: "Unitarity"

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KMC unitarity and new physics

Experimental constraints on the Kobayashi-Maskawa-Cabibbo (KMC) matrix are surveyed and shown to provide a test of the standard model at the level of its O (..cap alpha..) radiative corrections. The three generation prediction BR (K/sup +/ ..-->.. ..pi../sup +/..nu.. anti ..nu..) approx. = (0.35approx.3) x 10/sup -10/ is reviewed and the potential for enhancement up to approx. = 3 x 10/sup -9/ due to the fourth generation mixing is descibed. Constraints on additional neutral gauge boson masses … more

Date: September 1, 1986

Creator: Marciano, W. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Toward a general description of two-body hadron reactions

A model for describing two-body high energy hadron reactions at energies above the resonance region is presented. Although no real theory yet exists, one can give a procedure for obtaining a (possibly correct) description of the amplitudes for any two-body resction (whatever the spins involved, including real and imaginary parts of amplitudes, any helicity flip pi exchange as well as vector and tensor exchanges, etc.). The most important new physical effect involved is using the appropriate t-d… more

Date: January 1, 1973

Creator: Hartley, B.J. & Kane, G.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Eikonal field theory description of interacting pomerons. [Total cross sections, Feynman graphs, self-energy radiative correction, unitarity]

Starting from an underlying field theory in Eikonal approximation, interacting Pomerons are produced by retaining those Feynman graphs that correspond to self-energy and related radiative corrections. Multiple Reggeon t-channel thresholds may be viewed in a simple s-channel field theory framework, while the degree of s-channel unitarity required depends upon the spin content of the underlying field theory and the classes of permitted processes. An approximate Eikonal calculation suggests how re… more

Date: January 1, 1976

Creator: Fried, H. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

KMC unitarity and K/sup +/ yields. pi. /sup +/. nu. anti. nu

Experimental constraints on the Kobayashi-MaskawaCabibbo (KMC) matrix are surveyed and shown to provide a test of the standard model at the level of its O (..cap alpha..) radioactive corrections. The three generation prediction BR (K/sup +/ ..-->.. ..pi../sup +/..nu..) approx. = (0.35 approx. 3) x 10/sup 10/ is reviewed and the potential for enhancement up to approx. = 3 x 10/sup -9/ due to the fourth generation mixing is described. 19 refs.

Date: June 1, 1986

Creator: Marciano, William J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Modified method of perturbed stationary states. II. Semiclassical and low-velocity quantal approximations. [Unitarity, detailed balancing]

For one-electron heteropolar systems, the wave-theoretic Lagrangian of Paper I/sup 2/ is simplified in two distinct approximations. The first is semiclassical; the second is quantal, for velocities below those for which the semiclassical treatment is reliable. For each approximation, unitarity and detailed balancing are discussed. Then, the variational method as described by Demkov is used to determine the coupled equations for the radial functions and the Euler-Lagrange equations for the trans… more

Date: October 1, 1978

Creator: Green, T.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Three-body approach to the single scattering optical potential. [Watson and KMT multiple scattering theory]

The single scattering optical potential was in the multiple scattering approaches of Watson and KMT. Since the kinematics of single scattering is three-body in nature, one builds a three-body model of this term. This approach can include the proper kinematics for the struck nucleon, the identity of the target nucleons, and the binding interaction of the struck nucleon. Integral equations of the Faddeev type are derived for both the Watson and KMT single scattering optical potentials. Unitarity … more

Date: February 1, 1977

Creator: Tandy, P. C.; Redish, E. F. & Bolle, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Study of 14O as a Test of the Unitarity of the CKM Matrix and the CVC Hypothesis

Abstract: The study of superallowed beta decay in nuclei, in conjunction with other experiments, provide a test of the unitarity of the quark mixing matrix or CKM matrix. Nonunitarity of the CKM matrix could imply the existence of a fourth generation of quarks, right handed currents in the weak interaction, and/or new exotic fermions. Advances in radioactive beam techniques allow the creation of nearly pure samples of nuclei for beta decay studies. The subject of this thesis is the development … more

Date: June 1, 2004

Creator: Harke, Jason Timothy

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Discrete ambiguity resolution and baryon-resonance parameter determination. [1400 to 2200 MeV, causality, unitarity]

A partial-wave analysis was performed on elastic ..pi../sup +/p data between 1400 and 2200 MeV, using principles of analyticity (to select and amalgamate data), causality and unitarity together with Barrelet zeros are the resonating waves between 1500 and 1800 MeV examined in detail, and it is shown how a new resolution of the discrete ambiguity gives, for the S31 and D33 resonances, different parameters than found in an earlier resolution using less accurate information. In either case, mass d… more

Date: April 1, 1978

Creator: Chew, D.M & Urban, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Impact parameter study of elastic hadron--proton scattering at 50 and 175 GeV/c. Interim report No. 137. [Differential cross sections, optical model, partial waves]

In hadron-proton collisions at high energies, the impact profile function measures the range and strength of the strong interaction. It determines the effective size and shape of the hadrons involved, for purposes of both elastic scattering and particle production, but depends solely upon the behavior in t of the elastic differential cross-section. Such an analysis of the reactions ..pi.. +- p, K +- p, and p +- p at incident momenta from 50 to 175 GeV/c is presented using the elastic scattering… more

Date: April 1, 1976

Creator: Heltsley, B. K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Barrelet zeros and elastic. pi. /sup +/p partial waves. [1. 2 to 2. 2 GeV, partial-wave amplitudes]

A procedure is proposed for constructing low-order partial-wave amplitudes from a knowledge of Barrelet zeros near the physical region. The method is applied to the zeros already obtained for elastic ..pi../sup +/p scattering data between 1.2 and 2.2 GeV cm energies. The partial waves emerge with errors that are straight-forwardly related to the accuracy of the data and satisfy unitarity without any constraint being imposed. There are significant differences from the partial waves obtained by o… more

Date: June 1, 1976

Creator: Chew, D. M. & Urban, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Progress report for a research program in theoretical high-energy physics

No Description Available.

Date: June 1, 1974

Creator: Feldman, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Bootstrapping quarks and gluons

Dual topological unitarization (DTU) - the approach to S-matrix causality and unitarity through combinatorial topology - is reviewed. Amplitudes associated with triangulated spheres are shown to constitute the core of particle physics. Each sphere is covered by triangulated disc faces corresponding to hadrons. The leading current candidate for the hadron-face triangulation pattern employs 3-triangle basic subdiscs whose orientations correspond to baryon number and topological color. Additional … more

Date: April 1, 1979

Creator: Chew, Geoffrey F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Unitarity restrictions on semi-classical approximations to certain functional integrals

Estimates of physically relevant quantities (cross sections, multiplicities, correlations) in eikonal models of high-energy field theories lead to a class of semiclassical solutions to nonlinear Euler equations. The requirement of unitarity restricts these possible solutions to a unique function of energy and impact parameter.

Date: January 1, 1978

Creator: Fried, H. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Research in theoretical physics. Annual report, September 1, 1975--August 31, 1976. [Summaries of research activities at Johns Hopkins University]

Results are reported on an algebraic approach to the quark problem, strong coupling approximation to field theories and, spontaneous symmetry breaking in the presence of gravitation. A supersymmetry albebra was constructed which obeys triality exactly and allows for separate conservation of lepton and baryon numbers. The existence of higher lying color singlet states is predicted. Investigations into a perturbation expansion around a strong coupling (''independent valued'') limit of field theor… more

Date: April 1, 1976

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Polarized proton--proton scattering at intermediate energies. [Total cross sections, 400 to 1500 MeV, unitarity, partial waves]

Some aspects of the proton-proton spin-dependent total cross sections at 400 to 1500 MeV are studied in a model which is capable of describing elastic nucleon-nucleon scattering and pion production in a unitary way. The model is a three-body model for a system of two nucleons and a pion where the interaction occurs via the formation of quasi-particles. The energy dependence of the polarized total cross sections, whether the energy-dependence behavior is due to elastic or inelastic scattering, a… more

Date: January 1, 1978

Creator: Kloet, W.M. & Silbar, R.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Beyond the rising total cross sections

No Description Available.

Date: January 1, 1973

Creator: Wu, T. T. & Cheng, H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Four-body model of the four-nucleon system. [Phase shift total and differential cross sections, up to 25 MeV, scattering amplitudes]

Using a nonrelativistic field theoretic formalism a soluble model of the four-nucleon system is developed and solved numerically. Two- and three-body scattering proceeds through intermediate quasiparticles and the resulting T-matrices are separable in momentum space and satisfy two- and three-body unitarity. The 2+2 subamplitudes are treated exactly by the convolution method. The resulting four-body equations reduce to single variable integral equations following partial wave decomposition and … more

Date: June 1978

Creator: Fonseca, A. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Measurement of. pi. /sup -/p. -->. pi. /sup 0/. pi. /sup 0/n at 6, 8 and 12 GeV/c*. [Angular distributions, S-wave enhancement]

All ..gamma..'s and the neutron of this reaction are detected. From the experimental angular distributions the magnitude of the ..pi../sup 0/..pi../sup 0/ S-wave is determined for the ..pi pi.. mass range 600 to 1400 MeV and the cosinus of its phase angle (relatively to the known D-wave) is given for the range 1000 to 1400 MeV. The I = O amplitude S/sub 0/ is near the unitarity limit in the range 600 to 900 MeV and again around 1200 MeV. The data support the known facts of a very broad S-w… more

Date: January 1, 1978

Creator: Apel, W D; Auslander, J S & Muller, H

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Progress report for a research program in theoretical high-energy physics. [Summaries of research activities at Brown University]

Last year's research program dealt with a variety of topics including small-p/sub perpendicular/ hadronic phenomenology (dual topological unitarization, Pomeron-f identity hypothesis, t-channel approach to diffraction peak and hadron size, tunneling in Reggeon field theory); bound-state problems in quantum electrodynamics (positronium decay, hyperfine splitting of positronium and muonium); quantum field theory (graph counting, strong-coupling solutions for eikonal problems with SU(2) constraint… more

Date: October 1, 1978

Creator: Feldman, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department