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Hadronic loops and the OZI rule

Description: Arguments based on unitarity indicate that hadronic loop diagrams should produce large violations of the OZI (Okubo-Zweig-Iizuka) rule. The mechanism by which these corrections are evaded has long been a mystery. We have found that there is an exact cancellation of all such loops in a particular (quark model) limit and that, at least for the rho-->omega system which we have studied in detail, the cancellation is maintained in a realistic calculation which takes into account departures from this… more
Date: August 1, 1991
Creator: Isgur, Nathan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Heavy flavor lifetimes and lifetime differences

Description: The authors give an overview of heavy flavour lifetime measurements, focusing on recent results from the Tevatron and the B factories. In the first part of this article we summarize the status and latest measurements of B-hadron lifetimes and lifetime ratios, including some recent result from the Tevatron and the B factories, and compare those results with the predictions from Heavy Quark Expansion (HQE). Future prospects for lifetime measurements at the B factories and the Tevatron are discuss… more
Date: September 17, 2003
Creator: Rademacker, Jonas
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculation of 239Pu(n,2n) Cross Section by the Subtraction and the Ratio Methods

Description: The {sup 239}Pu(n,2n) and the {sup 235}U(n,2n) cross section are estimated by applying unitarity in several approaches: a subtraction method and also by using a ratio approach that relates the above cross sections to the {sup 238}U(n,2n) cross section and the {sup 239}Pu(n,2n) cross section to the {sup 235}U(n,2n) cross section, respectively. Also, a self-consistent, simultaneous analysis of the cross section data of four nuclei, {sup 239}Pu, {sup 235}U, {sup 238}U and {sup 232}Th, was undertak… more
Date: September 28, 2000
Creator: Mavratil, P. & McNabb, D.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Performance of CDF for B physics

Description: Hadron colliders can be an abundant source of heavy flavor, but pose a challenge to isolate the physics signals from the high backgrounds. The upgraded CDFII detector, with its precise tracking capabilities and powerful trigger system, is well equipped for this task. The detector is described with an emphasis on actual performance and on techniques to maximize the heavy flavor yield. Some first heavy flavor results are summarized.
Date: June 11, 2003
Creator: Oldeman, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The No-Higgs Signal: Strong WW Scattering at the LHC

Description: Strong WW scattering at the LHC is discussed as a manifestation of electroweak symmetry breaking in the absence of a light Higgs bosom. The general framework of the Higgs mechanism--with or without a Higgs boson--is reviewed, and unitarity is shown to fix the scale of strong WW scattering. Strong WW scattering is also shown to be a possible outcome of five-dimensional models, which do not employ the usual Higgs mechanism at the TeV scale. Precision electroweak constraints are briefly discussed.… more
Date: December 7, 2004
Creator: Chanowitz, Michael S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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MATRIX N/D METHOD WITH ABSORPTION AND THE UNITARITY PROBLEM IN COUPLED-CHANNEL REGGE THEORY

Description: In a crossing-symmetric Regge theory with several coupled two-particle channels, there are many-particle absorptive effects due to crossed two-particle processes. Also, some of the partial-wave amplitudes have overlapping left-hand and right-hand cuts in the s-plane, To enforce unitarity in such a theory, one needs a coupled-channel N/D method allowing arbitrary absorption parameters and overlapping cuts. These requirements lead to a nonlinear marginally singular N/D equation, which is proposed… more
Date: November 1, 1979
Creator: Warnock, Robert Lee
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prospects for measuring K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} and K{sub L}{sup 0} {r_arrow} {pi}{sup 0} {nu}{bar {nu}} at BNL

Description: Rare kaon decay experiments underway or planned for the BNL AGS will yield new and independent determinations of V*{sub ts}V{sub td}. A measurement of B(K{sub L}{sup 0} {r_arrow} {pi}{sup 0} {nu}{bar {nu}}) allows a determination of the imaginary part of this quantity, which is the fundamental CP-violating parameter of the Standard Model, in a uniquely clean manner. Since the measurement of B(K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}}) determines {vert_bar}V*{sub ts}V{sub td}, a complete der… more
Date: September 18, 2000
Creator: Bryman, D. A. & Littenberg, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Systematics of Baryon and Meson States

Description: Present information on established and possible baryons and mesons, its derivation, and its organization on the basis of unitary symmetry are discussed. Some questions of particular interest in connection with the last point are considered. 35 references. (D.C.W.)
Date: January 1, 1963
Creator: Dalitz, R H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Lattice QCD results for the B --> D(*) l nu form factors: F(1) and G(1)

Description: I review the current status of lattice QCD calculations of the B {yields} D and B {yields} D* form factors and discuss prospects for their improvement. Successful calculations within the quenched approximation demonstrate the power of lattice methods for calculating F(1) and G(1), and the unquenched calculations in progress should soon allow for a 2-3% exclusive determination of |Vcb|.
Date: January 1, 2007
Creator: Van de Water, R.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Strangeness in the Nucleon or the quark model beyond the valence approximation

Description: Simple arguments based on unitarity indicate that meson loops diagrams, induced by an underlying qq pair creation process, should badly disturb the phenomenologically successful spectroscopy and dynamics of the valence quark model, including such simple but mysterious regularities as the OZI rule. The author discusses some recent progress in adding pair creation to the valence quark model in a way which provides rationale for the quark model's success.
Date: January 1, 1999
Creator: Isgur, Nathan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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B to (rho/omega) gamma at BaBar

Description: This document describes the measurements of the branching fractions and isospin violations of the radiative electroweak penguin decays B {yields} ({rho}/{omega}){gamma} at the asymmetric-energy e{sup +}e{sup -} PEP-II collider with the BABAR detector. Together with the previously measured branching fractions of the decays B {yields} K*{gamma} the ratio of CKM-matrix elements |V{sub td}/V{sub ts}| are extracted and the length of the far side of the unitarity triangle is determined.
Date: February 6, 2008
Creator: Koeneke, Karsten
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Strongly coupled fermions in nature and the laboratory

Description: We report on recent work on the equation of state and pairing gap of neutron matter and cold atomic systems. Results of quantum Monte Carlo calculations show that the equations of state are very similar. The neutron matter pairing gap at low densities is found to be very large but, except at the smallest densities, significantly suppressed relative to cold atoms. We also discuss recent attempts to measure and extract the pairing gap in the fully paired superfluid state at unitarity.
Date: January 1, 2008
Creator: Carlson, Joseph; Gezerlis, Alexandros & Reddy, Sanjay
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of alpha / phi_2 from B to pi pi Decays

Description: The current results on B {yields} {pi}{pi} decays and SU(2) constraints on the Unitarity Triangle angle {alpha} or {phi}{sub 2} from the B-factories are summarized. Based on these measurements, predictions of the isospin analysis constraints at the end of the lifetime of both B-factories are given.
Date: January 17, 2007
Creator: Bevan, A.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Recent Measurements of sin2beta at BaBar

Description: The angle {beta} is the most accurately measured quantity that determines the Unitarity Triangle. In this article I review the various measurements of this angle performed by the BaBar Collaboration, and discuss their implications in the search for new physics.
Date: December 14, 2005
Creator: Sciolla, Gabriella
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bs physics and prospects at the Tevatron

Description: Both experiments CDF and D0 at the Tevatron collider have now the first samples of B{sub s} where preliminary measurements are performed. The mass and lifetime determination is shown and the yield for the hadronic B{sub s} decays, the first step towards the B{sub s} production fraction and Branching Ratio, is discussed. This also sets the bases for a re-evaluation of mixing capabilities in Run II.
Date: June 16, 2003
Creator: Lucchesi, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Higher-order corrections to BFKL evolution from t-channel unitarity

Description: Using reggeon diagrams as a partial implementation of t-channel unitarity, O(g{sup 4}) corrections to the BFKL evolution equation have been obtained. We describe the spectrum and holomorphic factorization properties of the resulting scale-invariant kernel. For a gauge theory, t-channel unitarity can be studied directly in the complex j-plane by implementing Ward identity constraints together with the group structure of reggeon interactions. We discuss how both the O(g{sup 2}) BFKL kernel and th… more
Date: 1994-12~
Creator: Coriano, C. & White, A. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Search for B^{+} \to \ell^{+} \nu_{\ell} Recoiling Against B^{-} \to D^{(*)0}\ell^{-}\bar{\nu}X

Description: We present a search for the decay B{sup +} {yields} {ell}{sup +} {nu}{sub {ell}} ({ell} = {tau}, {mu}, or e) in (458.9 {+-} 5.1) x 10{sup 6} {Upsilon}(4S) decays recorded with the BABAR detector at the SLAC PEP-IIB-Factory. A sample of events with one reconstructed exclusive semi-leptonic B decay (B{sup -} {yields} D{sup 0} {ell}{sup -}{bar {nu}}X) is selected, and in the recoil a search for B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}} signal is performed. The {tau} is identified in the follow… more
Date: April 17, 2009
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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How Well Do We Know the Unitarity Triangle? An Experimental Review

Description: In the past 10 years our knowledge of the parameters {rho} and {eta} of the Cabibbo-Kobayashi-Maskawa matrix has improved substantially. This article reviews the measurements that contributed to this advance, and discusses their implication in terms of understanding CP violation in the Standard Model and beyond.
Date: September 12, 2007
Creator: Sciolla, Gabriella
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CP VIOLATION HIGHLIGHTS: CIRCA 2005

Description: Recent highlights in CP violation phenomena, are reviewed. B-factory results imply that, CP-violation phase in the CKM matrix is the dominant contributor to the observed CP violation in K and B-physics. Deviations from the predictions of the CKM-paradigm due to beyond the Standard Model CP-odd phase are likely to be a small perturbation. Therefore, large data sample of clean B's will be needed. Precise determination of the unitarity triangle, along with time dependent CP in penguin dominated ha… more
Date: February 27, 2005
Creator: A., SONI
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurements of the CKM Angle Alpha at BaBar

Description: The authors present improved measurements of the branching fractions and CP-asymmetries fin the B{sup 0} {yields} {pi}{sup +}{pi}{sup -}, B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, and B{sup +} {yields} {rho}{sup +}{rho}{sup 0} decays, which impact the determination of {alpha}. The combined branching fractions of B {yields} K{sub 1}(1270){pi} and B {yields} K{sub 1}(1400){pi} decays are measured for the first time and allow a novel determination of {alpha} in the B{sup 0} {yields} {alpha}{sub 1}… more
Date: April 4, 2012
Creator: Stracka, Simone
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Alpha and Beta at the B Factories

Description: We review recent experimental results on time-dependent CP asymmetries in the B system from the BABAR and Belle experiments. Measurements of the {alpha} and {beta} angles of the Unitarity Triangle of the CKM matrix are discussed. These measurements constitute stringent tests of the Standard Model, and are also used to search for new physics.
Date: October 15, 2007
Creator: Finocchiaro, Giuseppe
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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