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Amplitude Analysis of B0 to K^ pi^-pi^0 and Evidence of Direct CP Violation in B to K^* pi decays

Description: We analyze the decay B{sup 0} {yields} K{sup +} {pi}{sup -} {pi}{sup 0} with a sample of 454 million B{bar B} events collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, and extract the complex amplitudes of seven interfering resonances over the Dalitz plot. These results are combined with amplitudes measured in B{sup 0} {yields} K{sup 0}{sub s}{pi}{sup +}{pi}{sup -} decays to construct isospin amplitudes from B{sup 0} {yields} K{sup *}{pi} and B{sup 0} {yields} {rho}K decays. We measure the phase of the isospin amplitude {Phi}{sub 3/2}, useful in constraining the CKM unitarity triangle angle {gamma} and evaluate a CP rate asymmetry sum rule sensitive to the presence of new physics operators. We measure direct CP violation in B{sup 0} {yields} K{sup *+}{pi}{sup -} decays at the level of 3 {sigma} when measurements from both B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} and B{sup 0} {yields} K{sup 0}{sub s}{pi}{sup +}{pi}{sup -} decays are combined.
Date: November 4, 2011
Creator: Lees, J. P.
Partner: UNT Libraries Government Documents Department

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

Description: 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 restricted triple-Pomeron interactions can serve to remove the bare Pomeron, and substitute an alternate asymptotic expression for o/sub TOT/.
Date: January 1, 1976
Creator: Fried, H. M.
Partner: UNT Libraries Government Documents Department

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

Description: 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 translational factors which are part of the theory. Specific semiclassical formulae for the translational factors are given in a many-state approximation. Low-velocity quantal formulae are obtained in a one-state approximation. The one-state results of both approximations agree with an earlier determination by Riley. 14 references.
Date: October 1, 1978
Creator: Green, T.A.
Partner: UNT Libraries Government Documents Department

Charged current unitarity and extra neutral gauge bosons

Description: The experimental status of the Kobayashi-Maskawa-Cabibbo (KMC) matrix is surveyed and shown to provide a precision test of the standard model at the level of its O(..cap alpha..) radiative corrections. Implications for new physics and constraints of extra neutral gauge bosons are described. 12 refs., 1 fig.
Date: March 1, 1987
Creator: Marciano, W.J. & Sirling, A.
Partner: UNT Libraries Government Documents Department

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

Description: 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, W.J.
Partner: UNT Libraries Government Documents Department

KMC unitarity and new physics

Description: 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 are also discussed. 23 refs.
Date: September 1, 1986
Creator: Marciano, W. J.
Partner: UNT Libraries Government Documents Department

Toward a general description of two-body hadron reactions

Description: 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-dependent phase for the vacuum exchange amplitude (the Pomeron''), both in elastic scattering and in describing absorption effects. The Pomeron is not a Regge pole. The model is very simple to formulate and has a reasonable physical interpretation in terms of important unitarity effects and absorption. It allows one to understand the partial successes and the inadequacies of previous approaches such as the dual absorptive model the strong absorption model, the view that some amplitudes have Regge pole behavior while others do not, etc, All the 0/sup -/1/2/sup +/ reactions, np yields pn, and pp yields nn, cross sections, polarizations, and amplitudes; these include all the important kinds of helicity amplitudes for any two-body resctions, Apart from a few places the results are very good; it is argued that the few places where there may be some difficulty are due to effects we have left out rather than to the structure of the model. Although the input Reggeon exchanges are not all exchange degenerate, the phases of the output amplitudes after absorption show a remarkable and unexpected resemblance to what one would expect from exchange degenerate poles, apart from the necessity of having a zero structure related to important absorption corrections, A number of related results, some of which are considered puzzles are discussed (total cross section differences for pi N and KN, the ...
Date: January 1, 1973
Creator: Hartley, B.J. & Kane, G.L.
Partner: UNT Libraries Government Documents Department

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

Description: 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 degeneracy of these resonances is observed in agreement with general considerations regarding smooth zero trajectories. 18 references.
Date: April 1, 1978
Creator: Chew, D.M & Urban, M.
Partner: UNT Libraries Government Documents Department

Bootstrapping quarks and gluons

Description: 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 peripheral triangles lie along the hadron-face perimeter. Certain combinations of peripheral triangles with a basic-disc triangle can be identified as quarks, the flavor of a quark corresponding to the orientation of its edges that lie on the hadron-face perimeter. Both baryon number and flavor are additively conserved. Quark helicity, which can be associated with triangle-interior orientation, is not uniformly conserved and interacts with particle momentum, whereas flavor does not. Three different colors attach to the 3 quarks associated with a single basic subdisc, but there is no additive physical conservation law associated with color. There is interplay between color and quark helicity. In hadron faces with more than one basic subdisc, there may occur pairs of adjacent flavorless but colored triangles with net helicity +-1 that are identifiable as gluons. Broken symmetry is an automatic feature of the bootstrap. T, C and P symmetries, as well as up-down flavor symmetry, persist on all orientable surfaces.
Date: April 1, 1979
Creator: Chew, G.F.
Partner: UNT Libraries Government Documents Department

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

Description: 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 theories were completed. The result is a generalized classical field theory with correct clustering properties; unitarity is satisfied at the tree diagram level. Vacuum solutions to conformal relativity were found, exhibiting spontaneous symmetry breaking. A ''second Higgs mechanism'' was discovered; as a consequence, scalar mesons are removed from the theory altogether. Significance of the results from the point of view of quark confinement and some cosmological consequences are discussed.
Date: April 1, 1976
Partner: UNT Libraries Government Documents Department

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]

Description: 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 data recently taken. Two derivations of the profile function are given: the classic optical model and the partial wave treatment. The first stresses the ''grey disc'' interpretations of hadrons; both allow the decomposition of the profile into the elastic and inelastic overlap functions, which represent the probabilities of each of the two processes. A more rigorous procedure yielding essentially the same result involves the imposition of unitarity on the relativistic S-matrix and then requiring angular momentum conservation. Cross section measurements extend to t = -0.8 (GeV/c)/sup 2/; this calculation assumes pure exponential behavior thereafter, and accounts for the possibility of a sharp decrease in its slope at larger t. The real part of the scattering amplitude is neglected. The results display good qualitative agreement with the shadow-diffraction scattering model, and with previous analyses. They indicate distinct differences between meson-baryon and baryon-baryon interactions, and imply that dependence of the cross section on energy derives primarily from a net change in peripheral processes. A test of the quark model and the Lipkin sum rules shows substantial deviation from theoretical expectations.
Date: April 1, 1976
Creator: Heltsley, B. K.
Partner: UNT Libraries Government Documents Department

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

Description: 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 other methods; this can be partially explained by the fact that no previous partial-wave analysis has been able to solve the discrete ambiguity. The cost of the analysis is much less.
Date: June 1, 1976
Creator: Chew, D. M. & Urban, M.
Partner: UNT Libraries Government Documents Department

Unitarity restrictions on semi-classical approximations to certain functional integrals

Description: 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.
Partner: UNT Libraries Government Documents Department

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

Description: 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 can be solved numerically by rotation of contour together with matrix inversion. A complete phase shift calculation is performed for the isospin triplet interaction. The differential cross sections for all two-to-two processes initiated by p + /sup 3/He, n + /sup 3/H and d + d are compared with experiment for energies up to 25 MeV in the center of mass. Total elastic and reaction cross sections for the processes initiated by n + /sup 3/H are also calculated and compared with experimental data.
Date: June 1978
Creator: Fonseca, A. C.
Partner: UNT Libraries Government Documents Department

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

Description: 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-wave enhancement on which is superimposed a large inelasticity due to the KK-threshold effect.
Date: January 1, 1978
Creator: Apel, W D; Auslander, J S & Muller, H
Partner: UNT Libraries Government Documents Department

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

Description: 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) constraints, unitarity restriction and semi-classical solutions, quark confinement); unified gauge models of weak and electromagnetic interactions (Weinberg-Salam model, exclusion of effective V/sub e/V/sub N/ + A/sub e/A/sub N/ neutral-current interaction, Cabibbo angle and quark mass ratios); bound-state mean field theory (structural equivalence of two-dimensional four-fermion and Yukawa-like models, renormalization of four-dimensional four-fermion models, Fermi theory of weak interactions as a Yang-Mills theory); acoustic detection of cosmic neutrinos; topics in gravitation and cosmology; as well as other studies involving the interactions of elementary particles. A list of publications is included.
Date: October 1, 1978
Creator: Feldman, D.
Partner: UNT Libraries Government Documents Department

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

Description: 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, and which partial waves are responsible for the strong energy dependence are treated. 13 references. (JFP)
Date: January 1, 1978
Creator: Kloet, W.M. & Silbar, R.R.
Partner: UNT Libraries Government Documents Department