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Strong effects in weak nonleptonic decays

Description: In this report the weak nonleptonic decays of kaons and hyperons are examined with the hope of gaining insight into a recently proposed mechanism for the ..delta..I = 1/2 rule. The effective Hamiltonian for ..delta..S = 1 weak nonleptonic decays and that for K/sup 0/-anti K/sup 0/ mixing are calculated in the six-quark model using the leading logarithmic approximation. These are used to examine the CP violation parameters of the kaon system. It is found that if Penguin-type diagrams make import… more
Date: April 1, 1980
Creator: Wise, M.B.
Partner: UNT Libraries Government Documents Department
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Particle identification at an asymmetric B Factory

Description: Particle identification systems are an important component of any detector at a high-luminosity, asymmetric B Factory. In particular, excellent hadron identification is required to probe CP violation in B{sup 0} decays to CP eigenstates. The particle identification systems discussed below also provide help in separating leptons from hadrons at low momenta. We begin this chapter with a discussion of the physics motivation for providing particle identification, the inherent limitations due to int… more
Date: September 1, 1991
Creator: Coyle, P.; Eigen, G.; Hitlin, D.; Oddone, P.; Ratcliff, B.; Roe, N. et al.
Partner: UNT Libraries Government Documents Department
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Properties of D* production in e/sup +/e/sup -/ annihilation at 29 GeV

Description: D* production is studied in the decay chain D*/sup +/ ..-->.. D/sup 0/ ..pi../sup +/ with the D/sup 0/ observed in the K/sup -/..pi../sup +/ mode and the corresponding charge conjugate decays. The results were obtained from a preliminary analysis of an 80 pb/sup -1/ data sample of e/sup +/e/sup -/ annihilations at 29 GeV taken with the High Resolution Spectrometer at PEP. The excellent mass resolution of the HRS allows the study of the D* production and decay with very low background. We presen… more
Date: January 1, 1983
Creator: Ahlen, S.; Akerlof, C.; Baranko, G.; Baringer, P.; Beltrami, I.; Bender, D. et al.
Partner: UNT Libraries Government Documents Department
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Charmed baryon decays observed in e/sup +/e/sup -/ annihilation at SPEAR

Description: Various weak decays of the charmed baryon ..lambda../sub c/ are observed in the Mark II detector at the SLAC e/sup +/e/sup -/ storage ring SPEAR. Hadronic decays ..lambda../sub c//sup +/ ..-->.. pK/sup -/..pi../sup +/ and ..lambda../sub c//sup +/ ..-->.. pK/sub s//sup 0/ and their conjugates are observed as peaks in invariant mass spectra at m(..lambda../sub c/) = (2286 +- 6) MeV/c/sup 2/. An estimate of the charmed baryon production cross section, sigma(..lambda../sub c/) + sigma (anti ..lambd… more
Date: December 1, 1981
Creator: Vella, E.N.
Partner: UNT Libraries Government Documents Department
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Experiments on the nuclear interactions of pions and electrons. [Dept. of Physics, Univ. of Virginia]

Description: The analysis of the deuterium content in the CD target used in an experiment to study the [pi] + d [yields] 2p reaction at incident pion energies from 4 to 20 MeV was completed. The final paper describing this experiment will be submitted for publication this summer. Analysis of LAMPF Exp. on pion absorption in [sup 4]He is continuing. In 1991, we collaborated with D. Pocanic from the Univ. of Virginia on a measurement at LAMPF of the [pi][sup 0] production in [pi] + p interactions. This run pr… more
Date: August 1, 1992
Creator: Minehart, R.C. & Ziock, K.O.H.
Partner: UNT Libraries Government Documents Department
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Experimental Investigations in Particle Physics at Intermediate Energies Preformance Report: December 1991-November 1992

Description: The major emphasis of this project continues to be on fundamental symmetries and parameters of the Standard Model. A test of a quark model prediction was also done. The projects in the current period have been the following: LSND, a neutrino oscillation experiment at LAMPF; E791, a search for the decays K{sub L}{sup 0} {yields} {mu}e and K{sub L}{sup 0} {yields} ee; E871, tests and preparations for an upgrade proposal; and E888, a search for the H dibaryon. The LSND (Large Scintillator Neutrino… more
Date: July 12, 1992
Creator: Auerbach, L. B.; Highland, V. L.; McFarlane, K. W. & Kettell, S. H.
Partner: UNT Libraries Government Documents Department
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Measurement of the B{sub s} meson lifetime at CDF

Description: Proton-antiproton collision data corresponding to a total integrated luminosity of {approximately} 21 pb{sup {minus}1} were collected with the CDF detector at the Fermilab Tevatron collider during 1992--1993. The lifetime of the B{sub s} meson is measured using events from the semileptonic decay B{sub s} {yields} {ell}{sup +}{nu}D{sub s}{sup {minus}}X and from the exclusive decay B{sub s} {yields} J/{psi}{phi}. For the semileptonic decay channel, 76 {ell}{sup +}D{sub s}{sup {minus}} signal even… more
Date: June 1, 1994
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department
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Family symmetries and proton decay

Description: The proton decay modes p {yields} K{sup 0}e{sup +} and p {yields} K{sup 0}{mu}{sup +} may be visible in certain supersymmetric theories, and if seen would provide evidence for new flavor physics at extremely short distances. These decay modes can arise from the dimension five operator (Q{sub 1}Q{sub 1}Q{sub 2}L{sub 1,2}), where Q{sub i} and L{sub i} are i{sup th} generation quark and lepton superfields respectively. Such an operator is not generated at observable levels due to gauge or Higgs bo… more
Date: August 1, 1994
Creator: Murayama, Hitoshi & Kaplan, D. B.
Partner: UNT Libraries Government Documents Department
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D{sup 0}-{anti D}{sup 0} mixing and doubly Cabibbo-suppressed decays of the D{sup +}

Description: This report summarizes results from Fermilab experiment E791 on D{sup 0}-{anti D}{sup 0} mixing and doubly Cabibbo-suppressed decays of the D{sup +} meson. In order to search for D{sup 0}-{anti D}{sup 0} mixing, the authors use only D{sup 0} mesons from D{sup *+} decays in which case the charge of the pion from the D{sup *+} decay identifies the charm quantum number of the D{sup 0} at birth. When the D{sup 0} decays, the charge of the kaon identifies the charm quantum number and this way one ca… more
Date: July 1, 1994
Creator: Fermilab E791 Collaboration
Partner: UNT Libraries Government Documents Department
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Production asymmetries in x{sub F} and P{sub t}{sup 2} for D{sup {+-}} mesons

Description: Non-zero asymmetries have been reported in x{sub f} distributions of leading and non-leading charmed mesons produced from hadronic beams. Production models have also been proposed that would explain these asymmetries and make predictions on how these asymmetries will depend on P{sub t}{sup 2}. The authors present differences in leading and non-leading D charged meson production as a doubly differential function of both P{sub t}{sup 2} and x{sub f}. This information is from the preliminary analy… more
Date: July 1, 1994
Creator: E791 Collaboration
Partner: UNT Libraries Government Documents Department
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Measurement of the B meson differential cross-sections in p{anti p} collisions at {radical}s = 1.8 TeV using the exclusive decays B{sup {+-}} {yields} J/{psi}K{sup {+-}} and B{sup 0} {yields} J/{psi}K*{sup 0}

Description: This paper presents the first measurement of the differential B{sup {+-}} and B{sup 0} cross-sections, d{sigma}/dp{sub {Tau}}, in p{anti p} collisions at {radical}s = 1.8 TeV. The data sample used represents an integrated luminosity of 19.3 {+-} 0.8 pb{sup {minus}1} accumulated by the Collider Detector at Fermilab (CDF). The cross-sections are measured over the p{sub T} range 6--15 GeV/c in the central pseudorapidity region {vert_bar}{eta}{vert_bar} < 1 by fully reconstructing the B meson decay… more
Date: June 1, 1994
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department
open access

Experiments on the nuclear interactions of pions and electrons. Progress report

Description: The analysis of the deuterium content in the CD target used in an experiment to study the {pi} + d {yields} 2p reaction at incident pion energies from 4 to 20 MeV was completed. The final paper describing this experiment will be submitted for publication this summer. Analysis of LAMPF Exp. on pion absorption in {sup 4}He is continuing. In 1991, we collaborated with D. Pocanic from the Univ. of Virginia on a measurement at LAMPF of the {pi}{sup 0} production in {pi} + p interactions. This run pr… more
Date: August 1, 1992
Creator: Minehart, R. C. & Ziock, K. O. H.
Partner: UNT Libraries Government Documents Department
open access

Elementary Particle Physics and High Energy Phenomena. Progress Report for FY93

Description: Experimental and theoretical high-energy physics programs at the University of Colorado are reported. Areas of concentration include the following: study of the properties of the Z{sup 0} with the SLD detector; fixed-target K-decay experiments; the R&D program for the muon system: the SDC detector; high-energy photoproduction of states containing heavy quarks; electron--positron physics with the CLEO II detector at CESR; lattice QCD; and spin models and dynamically triangulated random surfaces.… more
Date: June 1, 1992
Creator: Barker, A. R.; Cumalat, J. P.; De Alwis, S. P.; DeGrand, T. A.; Ford, W. T.; Mahanthappa, K. T. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for D{sup +} {yields} {pi}{sup +}{mu}{sup +}{mu}{sup {minus}}

Description: Flavor-changing neutral current decays are forbidden in lowest order in the Standard Model. The authors present results of a search for the charm changing neutral current decay D{sup +} {yields} {pi}{sup +}{mu}{sup +}{mu}{sup {minus}} based on the analysis of one third of the data from Fermilab experiment E791, accumulated during the 1991--92 fixed target run with a 500 GeV negative pion beam incident on a segmented target. Assuming that the decay kinematics are the same as for D{sup +} {yields… more
Date: July 1994
Creator: Fermilab E791 Collaboration
Partner: UNT Libraries Government Documents Department
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Beam flavor dependence in the hadroproduction of D{sup {+-}} and D{sub s}{sup {+-}} mesons

Description: Fermilab E769, a fixed-target experiment conducted during the 1987--88 running period, yielded large numbers of charm particles. Through collisions of 250 GeV {pi}{sup {+-}}, K{sup {+-}}, and p on a multifoil target, E769 allows for studies of beam flavor dependence in the hadroproduction of charm. Through the decay modes D{sup +} {yields} K{sup {minus}}{pi}{sup +}{pi}{sup +}, D{sub s}{sup +} {yields} {phi}{pi}{sup +}, and D{sub s}{sup +} {yields} {anti K}{sup *0} K{sup +} (and charge conjugate… more
Date: July 1, 1994
Creator: Collaboration, Fermilab E769
Partner: UNT Libraries Government Documents Department
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Measurement of the Branching Fraction And Search for Direct CP-Violation in the B+- --> J/Psi Pi+- Decay Mode at BaBar

Description: The phenomenon of CP-violation in weak interactions, discovered in 1964 in decays of neutral kaons, receives a simple and elegant explanation in the Standard Model with three generations of quarks. Indeed, in this model the common source of CP-asymmetry phenomena is represented by a simple complex phase in the unitary matrix (the Cabibbo-Kobayashi-Maskawa matrix) describing the charged weak couplings of the quarks. This simple scheme has never received an accurate validation, because the phenom… more
Date: August 22, 2006
Creator: Fobozzi, Francesco & U., /Naples
Partner: UNT Libraries Government Documents Department
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Search for charmed F mesons in e/sup +/e/sup -/ collisions with the crystal ball

Description: In this work an experimental search for the production of the charmed F and F* mesons in e/sup +/e/sup -/ collisions is presented. The data for this analysis were obtained over a center of mass energy region from 3.86 GeV to 4.5 GeV with the Crystal Ball detector at SPEAR. The inclusive eta production cross section has been measured as a function of the center of mass energy. It was found to be almost constant with no indication for an significant increase which was cited as evidence for F prod… more
Date: January 1, 1984
Creator: Horisberger, R.P.
Partner: UNT Libraries Government Documents Department
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Decays of the Heavy Lepton, Tau (1785)

Description: The structure of the weak hadronic current coupled to the tau is investigated via some of the hadronic decays of the tau. The vector current coupling is determined by measuring the tau ..-->.. rho ..nu../sub tau/ branching ratio. The axial-vector coupling is determined by measuring the tau ..-->.. ..pi.. ..nu../sub tau/ branching ratio. The Cabibbo structure of the hadronic current is established by observing the decay tau ..-->.. K*(890)..nu../sub tau/ and measuring its branching ratio. The br… more
Date: April 1, 1980
Creator: Blocker, C. A.
Partner: UNT Libraries Government Documents Department
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Three-jet distributions from weak decay of heavy particles. [Final-state gluon]

Description: Several sources of 3-jet final states produced by the weak decay of mesons containing heavy quarks are examined. Some of the results are applicable to the decay of the W boson into 3 jets. It is found that vector meson 3-jet final states have the same x, spherocity, and thrust distributions as the q anti q g final state of e/sup +/e/sup -/. For pseudoscalar mesons it is found that the 3-jet branching ratio is suppresed by ratios of the final quark masses to the original meson mass. 37 reference… more
Date: April 1, 1979
Creator: Rizzo, Thomas G.
Partner: UNT Libraries Government Documents Department
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Measurement of the inclusive branching fraction tau/sup -/. -->. nu/sub tau/. pi. /sup -/. pi. /sup 0/ + neutral meson(s)

Description: This dissertation measures an inclusive branching fraction of (13.9 +- 2.0/sub -2.4//sup +2.1/)% for the decay tau/sup -/ ..-->.. nu/sub tau/..pi../sup -/..pi../sup 0/ + nh/sup 0/ where h/sup 0/ is a ..pi../sup 0/ or an eta and n greater than or equal to 1. The data sample, obtained with the TPC detector facility at PEP, corresponds to an integrated luminosity of 72 pb/sup -1/ at 29 GeV center of mass energy. The measured value for this branching fraction is somewhat greater than the theoretica… more
Date: December 1, 1986
Creator: Moses, W. W.
Partner: UNT Libraries Government Documents Department
open access

Elementary Particle Physics and High Energy Phenomena. [Dept. Of Physics, Univ. Of Colorado, Boulder, Colorado]

Description: Experimental and theoretical high-energy physics programs at the University of Colorado are reported. Areas of concentration include the following: study of the properties of the Z[sup 0] with the SLD detector; fixed-target K-decay experiments; the R D program for the muon system: the SDC detector; high-energy photoproduction of states containing heavy quarks; electron--positron physics with the CLEO II detector at CESR; lattice QCD; and spin models and dynamically triangulated random surfaces.… more
Date: June 1, 1992
Creator: Barker, A. R.; Cumalat, J. P.; De Alwis, S. P.; DeGrand, T. A.; Ford, W. T.; Mahanthappa, K. T. et al.
Partner: UNT Libraries Government Documents Department
open access

Photon detector for MEGA. Progress report, July 16, 1991--May 31, 1992

Description: The MEGA photon detector is designed to observe the 52.83-MeV photon produced in a {mu} {yields} e{gamma} decay with an energy resolution of 1.25 MeV, a position resolution of 2 {times} 5 mm{sup 2}, a directional resolution of 10{degree}, a time resolution of 500 ps, and an efficiency of about 5.4%. It will consist of three independent concentric cylindrical pair spectrometers mounted within a 1.5 T magnetic field produced by a superconducting solenoid magnet. Each pair spectrometer includes tw… more
Date: December 1, 1992
Creator: Gagliardi, C. A. & Tribble, R. E.
Partner: UNT Libraries Government Documents Department
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Experimental investigations in particle physics at intermediate energies. [Annual] performance report, December 1, 1991--November 30, 1992

Description: The major emphasis of this project continues to be on fundamental symmetries and parameters of the Standard Model. A test of a quark model prediction was also done. The projects in the current period have been the following: LSND, a neutrino oscillation experiment at LAMPF; E791, a search for the decays K{sub L}{sup 0} {yields} {mu}e and K{sub L}{sup 0} {yields} ee; E871, tests and preparations for an upgrade proposal; and E888, a search for the H dibaryon. The LSND (Large Scintillator Neutrino… more
Date: July 12, 1992
Creator: Auerbach, L. B.; Highland, V. L.; McFarlane, K. W. & Kettell, S. H.
Partner: UNT Libraries Government Documents Department
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