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144 results on '"M. Hempstead"'

1. Time-Resolved Performance Analysis of a Second-Order PMD Compensator

Author

M.J. Soulliere, U. Neukirch, M. Anderegg, Dragan Pikula, Michael Brian Webb, Garrett Andrew Piech, D. Sobiski, R. Hoyt, Yihong Mauro, M. Hempstead, Michal Mlejnek, Michael J. Dailey, Feiling Wang, and C. Drewnowski

Subjects
Control theory, Polarization mode dispersion, Detector, Bit error rate, Electronic engineering, Optical communication, Degrees of freedom (statistics), Probability distribution, Signal, Atomic and Molecular Physics, and Optics, Group delay and phase delay, Mathematics
Abstract

Design, test, and performance requirement and analysis for a polarization-mode-dispersion compensator (PMDC) with four degrees of freedom is presented. The performance is analyzed on the basis of time-integrated and time-resolved bit-error ratio (BER) measurements. Signal impairments are generated by both, first- and higher-order emulators. The probability distributions of bit errors measured over many one second intervals exhibit very long tails. Therefore even a PMDC with a good average BER performance may result in a significant total outage time for a given system.

Published
2004

2. Relief gratings on Er/Yb-doped borosilicate glasses and waveguides by excimer laser ablation

Author

Laurence Reekie, James S. Wilkinson, Stavros Pissadakis, M. Hempstead, and Michael Zervas

Subjects
Diffraction, Fabrication, Materials science, Laser ablation, Excimer laser, business.industry, Borosilicate glass, medicine.medical_treatment, Physics::Optics, General Physics and Astronomy, Surfaces and Interfaces, General Chemistry, Grating, Condensed Matter Physics, Diffraction efficiency, Surfaces, Coatings and Films, Optics, medicine, Physics::Atomic Physics, business, Diffraction grating
Abstract

Relief gratings have been fabricated on Er/Yb-doped borosilicate glass substrates by laser ablation using a 193 nm excimer laser and a modified Mach-Zehnder interferometer. The grating fabrication process was quantified using diffraction efficiency measurements and related to the incident energy density. Diffraction efficiencies and grating profiles are presented for gratings fabricated using different pulse energy densities and number of pulses, and optimised fabrication conditions are proposed. Finally, relief gratings were applied to ion-exchanged channel waveguides and spectral transmission measurements are presented.

Published
2000

3. Spectral properties of Er3+-doped gallium lanthanum sulphide glass

Author

M. Hempstead, Daniel W. Hewak, David N. Payne, C.C. Ye, and B.N. Samson

Subjects
Materials science, Absorption spectroscopy, Doping, Analytical chemistry, Physics::Optics, chemistry.chemical_element, Chalcogenide glass, Mineralogy, Condensed Matter Physics, Condensed Matter::Disordered Systems and Neural Networks, Electronic, Optical and Magnetic Materials, chemistry, Materials Chemistry, Ceramics and Composites, Radiative transfer, Lanthanum, Gallium, Absorption (electromagnetic radiation), Refractive index
Abstract

The spectral properties of chalcogenide glass 0.7Ga2S3:0.3La2S3 (Ga:La:S) doped with Er3+ are presented and discussed. Emission and absorption spectra and lifetimes of energy levels have been measured. The 2.7 km emission of Er3+ has been observed from chalcogenide glass for the first time. Radiative and non-radiative transition rates are calculated and compared with the measured lifetimes of interesting energy levels. Comparing this glass with Er3+-doped silica glasses, it is shown that the absorption and emission cross-sections of Er3+-doped Ga:La:S are around 2.5 times higher, radiative transition rates are around five times higher due to its higher refractive index, while multiphonon non-radiative decay rates are around three orders lower due to its much lower phonon energy. Furthermore, the inverse energy transfer process in Er3+:Ga:La:S glass may have significant implications for the operation of Er3+:Ga:La:S devices. These spectral properties, along with the higher solubility for rare earth-ions in Ga:La:S, make this glass a good candidate for new applications

Published
1996

4. Waveguide lasers operating at 1084 nm in neodymium-diffused lithium niobate

Author

M. Hempstead, James S. Wilkinson, and Laurence Reekie

Subjects
Materials science, business.industry, Lithium niobate, Slope efficiency, Physics::Optics, chemistry.chemical_element, Laser pumping, Laser, Waveguide (optics), Neodymium, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, law.invention, chemistry.chemical_compound, Optics, chemistry, law, Diode-pumped solid-state laser, Electrical and Electronic Engineering, business, Lasing threshold
Abstract

The authors report the demonstration of waveguide lasers in lithium niobate into which the active element neodymium has been introduced by thermal diffusion. The waveguides were fabricated using conventional Ti indiffusion and optical feedback was provided by the polished endfaces alone. The absorbed power threshold of one waveguide laser was estimated at 13+or-3 mW for pumping at 814 nm, and its slope efficiency in terms of total lasing output as a function of absorbed pump power was estimated to be 55+or-8%. Laser output powers in excess of 100 mW were observed. >

Published
1992

5. Beat-length measurement in directional couplers by thermo-optic modulation

Author

Reinhard Ulrich, J.E. Román, James S. Wilkinson, M. Hempstead, and H. Gnewuch

Subjects
Physics, business.industry, Beat (acoustics), Lambda, Atomic and Molecular Physics, and Optics, Semiconductor laser theory, Length measurement, Optics, Fiber laser, Optoelectronics, Power dividers and directional couplers, Integrated optics, Hybrid coupler, business
Abstract

In integrated optical directional couplers formed by two parallel waveguides, we measure the difference Δβ = βeven - βodd between the propagation constants of the 'supermodes'. They are coupled locally by heating a fine spot on one of the guides. When the spot is scanned along the coupler the output power from one of the guides is found to vary periodically. The period of variation is the modal beat length λ = 2π/Δβ. We demonstrate this technique with directional couplers fabricated by K+-exchange in glass. Beat lengths in the range of 0.6 ... 2.2 mm are measured with an accuracy of ±0.3%.

Published
2009

6. Channel waveguide laser at 1 microm in Yb-indiffused LiNbO(3)

Author

J.K. Jones, Anne C. Tropper, M. Hempstead, David Shepherd, James S. Wilkinson, A.C. Large, and J.P. de Sandro

Subjects
Ytterbium, Materials science, Annealing (metallurgy), business.industry, Slope efficiency, Doping, Lithium niobate, Physics::Optics, chemistry.chemical_element, Output coupler, Laser, Atomic and Molecular Physics, and Optics, law.invention, chemistry.chemical_compound, Optics, chemistry, law, business, Lasing threshold
Abstract

We report laser action in a Ti-diffused LiNbO(3) waveguide doped with trivalent Yb ions by thermal indiffusion. Lasing was observed at 1008, 1030, and 1060 nm with thresholds as low as 15-mW launched pump power. We reduced photorefractivity, which initially permitted only intermittent lasing, by annealing the sample in wet O(2). The annealed sample lased continuously in a cavity formed by high-ref lectivity mirrors; however, with a 7% output coupler the output power exhibited instabilities. The greatest value of the output power observed under these conditions was consistent with a slope efficiency of ~16% with respect to absorbed power.

Published
2009

7. Study ofπ+π−transitions from theϒ(3S)and a search for thehb

Author

R. DeSalvo, G. C. Moneti, E. I. Shibata, Thomas Ferguson, A. M. Halling, Y. Kubota, M. Worris, D. L. Hartill, R. Poling, Daniela Bortoletto, F. Morrow, J. W. Dewire, B. Gittelman, Ian Shipsey, D. Chen, V. Sharma, I. J. Kim, W. C. Li, M. Procario, R. Ehrlich, Xinchou Lou, T. Jensen, R. Fulton, C. Bebek, E. Nordberg, L. Garren, R. L. McIlwain, T. Skwarnicki, D. Besson, A. Silverman, R. Ng, F. M. Pipkin, M. D. Mestayer, M. S. Alam, T. Copie, D. G. Cassel, S. Nandi, P. Baringer, T. Letson, D. H. Miller, D. L. Kreinick, H. Kagan, Richard Wilson, P. Lubrano, R. S. Galik, James Mueller, S. E. Csorna, R. Holmes, K. Kinoshita, D. Riley, P. Haas, J. Byrd, M. Hempstead, A. J. Sadoff, T. J. V. Bowcock, D. Xiao, D. M. Coffman, John Yelton, B. K. Heltsley, E. Blucher, N. Horwitz, R. Namjoshi, Elliott Cheu, Glen D. Crawford, M. Pisharody, Karl Berkelman, V. Tanikella, D. R. Johnson, J. Kandaswamy, A. Jawahery, D. Peterson, Ian Brock, R. Kowalewski, C. H. Park, N. B. Mistry, Hans J. Vogel, N. Katayama, M. Goldberg, J. Wolinski, J. D. Lewis, C. R. Sun, R. D. Kass, Sheldon Stone, Paul Avery, D. Perticone, S. W. Gray, and J. Whitmore

Subjects
Physics, Crystallography, Particle decay, ComputingMilieux_THECOMPUTINGPROFESSION, Meson, Branching fraction, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Electron–positron annihilation, Hadron, Bound state, Dalitz plot, Elementary particle
Abstract

We have investigated the transitions {Upsilon}(3{ital S}){r arrow}{pi}{sup +}{pi}{sup {minus}}{Upsilon}(1{ital S}), {Upsilon}(3{ital S}){r arrow}{pi}{sup +}{pi}{sup {minus}}{Upsilon}(2{ital S}) and the cascade process {Upsilon}(3{ital S}){r arrow}{Upsilon}(2{ital S})+{ital X},{Upsilon}(2{ital S}){r arrow}{pi}{sup +}{pi}{sup {minus}}{Upsilon}(1{ital S}), both in the exclusive decay mode, with the daughter {Upsilon} state decaying into two leptons, and in the inclusive decay mode, with the daughter {Upsilon} state decaying hadronically. Results are presented on the branching fractions and properties of the {pi}{sup +}{pi}{sup {minus}} system. The {pi}{sup +}{pi}{sup {minus}} invariant-mass spectra for the decays {Upsilon}(3{ital S}){r arrow}{pi}{sup +}{pi}{sup {minus}}{Upsilon}(1{ital S}) and {Upsilon}(3{ital S}){r arrow}{pi}{sup +}{pi}{sup {minus}}{Upsilon}(2{ital S}) are measured and compared with theoretical predictions. We also present the results of a search for the {ital h}{sub {ital b}}(1 {sup 1}{ital P}{sub 1}) and {Upsilon}(1 {sup 3}{ital D}) states in inclusive {Upsilon}(3{ital S}) decays, and for the exclusive decay {Upsilon}(3{ital S}){r arrow}{eta}{Upsilon}(1{ital S}).

Published
1991

8. Measurement of γγ widths of charmonium states

Author

N. Katayama, P. Wilson, D. L. Hartill, R. Poling, R. Fulton, B. Gittlman, A. Silverman, W. M. Yao, D. L. Kreinick, E. Nordberg, C. O'Grady, H. Kagan, G. C. Moneti, M. S. Alam, Tomasz Skwarnicki, F. Morrow, E. I. Shibata, A. J. Sadoff, K. Sparks, Themistocles Bowcock, V. Jain, C. R. Ng, M. Procario, W. C. Li, M. Thulasidas, C. H. Park, John Yelton, Daniela Bortoletto, Marina Artuso, T. Jensen, R. L. McIlwain, D. M. Coffman, H. Worden, N. B. Mistry, L. Garren, B. K. Heltsley, S. W. Gray, J. W. Dewire, M. Pisharody, Karl Berkelman, Elliott Cheu, Glen D. Crawford, V. Sharma, R. Ehrlich, M. Sapper, J. Whitmore, N. Horwitz, Chunjie Wang, J. Kandaswamy, R. Ammar, D. Perticone, P. N. Wang, P. Haas, James Mueller, D. Peterson, Philip Baringer, D. R. Johnson, A. Jawahery, D. Xiao, D. Besson, E. H. Thorndike, F. M. Pipkin, D. Coppage, P.S. Dell, S. E. Csorna, M. I. Zoeller, K. Kinoshita, R. Namjoshi, T. Letson, D. H. Miller, Ha Lam, J. D. Lewis, C. Bebek, W. Y. Chen, C. R. Sun, R. D. Kass, M. Goldberg, A. M. Halling, M. Worris, J. Wolinski, D. Riley, Sheldon Stone, Xinchou Lou, S. F. Schaffner, Paul Avery, M. Hempstead, Yuichi Kubota, Richard Wilson, D. G. Cassel, James Alexander, S. Nandi, J. K. Nelson, M. D. Mestayer, I. J. Kim, R. S. Galik, and Ian Shipsey

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, Antiparticle, Condensed matter physics, Meson, Branching fraction, Molecular, Quarkonium, Atomic, Nuclear & Particles Physics, Nuclear physics, Particle decay, Particle and Plasma Physics, Pair production, Nuclear, Cornell Electron Storage Ring, Mathematical Physics, Astronomical and Space Sciences
Abstract

Using the CLEO detector at the Cornell Electron Storage Ring, we have searched for two-photon production of charmonium in four-track final states. We have measured Γ γγ ( η c )=5.9 +2.1 −1.8 ±1.9 keV, and we have obtained 95% CL upper limits of Γ γγ ( X c 0 ) Γ γγ ( X c 2 )

Published
1990

9. Exclusive and inclusive decays ofBmesons intoDsmesons

Author

D. Bortoletto, M. Goldberg, N. Horwitz, V. Jain, M. D. Mestayer, G. C. Moneti, V. Sharma, I. P. J. Shipsey, T. Skwarnicki, M. Thulasidas, S. E. Csorna, T. Letson, J. Alexander, M. Artuso, C. Bebek, K. Berkelman, D. G. Cassel, E. Cheu, D. M. Coffman, G. Crawford, J. W. DeWire, P. S. Drell, R. Ehrlich, R. S. Galik, B. Gittelman, S. W. Gray, A. M. Halling, D. L. Hartill, B. K. Heltsley, J. Kandaswamy, N. Katayama, D. L. Kreinick, J. D. Lewis, N. B. Mistry, J. Mueller, R. Namjoshi, S. Nandi, E. Nordberg, C. O’Grady, D. Peterson, M. Pisharody, D. Riley, M. Sapper, A. Silverman, S. Stone, H. Worden, M. Worris, A. J. Sadoff, P. Avery, D. Besson, L. Garren, J. Yelton, T. Bowcock, K. Kinoshita, F. M. Pipkin, M. Procario, Richard Wilson, J. Wolinski, D. Xiao, R. Ammar, P. Baringer, D. Coppage, P. Haas, Ha Lam, A. Jawahery, C. H. Park, Y. Kubota, J. K. Nelson, D. Perticone, R. Poling, R. Fulton, M. Hempstead, T. Jensen, D. R. Johnson, H. Kagan, R. Kass, F. Morrow, J. Whitmore, P. Wilson, W.-Y. Chen, R. L. McIlwain, J. Dominick, D. H. Miller, C. R. Ng, S. F. Schaffner, E. I. Shibata, W.-M. Yao, K. Sparks, E. H. Thorndike, C.-H. Wang, M. S. Alam, I. J. Kim, W. C. Li, X. C. Lou, C. R. Sun, P.-N. Wang, and M. I. Zoeller

Subjects
Physics, Statistics::Theory, Particle physics, Statistics::Applications, Meson, Branching fraction, High Energy Physics::Phenomenology, Hadron, General Physics and Astronomy, Elementary particle, Particle decay, High Energy Physics::Experiment, Production (computer science), B meson, Boson
Abstract

We have studied the production of ${\mathit{D}}_{\mathit{s}}$ mesons in the decays of B mesons at the \ensuremath{\Upsilon}(4S) resonance. We report on the first observation of exclusive B-meson decays B-g${\mathit{D}}_{\mathit{s}}^{\mathrm{\ensuremath{-}}}$${\mathit{D}}^{\mathrm{*}+}$, B\ensuremath{\rightarrow}${\mathit{D}}_{\mathit{s}}^{\mathrm{\ensuremath{-}}}$${\mathit{D}}^{+}$, and B\ensuremath{\rightarrow}${\mathit{D}}_{\mathit{s}}^{\mathrm{\ensuremath{-}}}$${\mathit{D}}^{0}$. We also present a new measurement of the branching ratio and the momentum spectrum for the inclusive decay B\ensuremath{\rightarrow}${\mathit{D}}_{\mathit{s}}$X.

Published
1990

10. Radiativeϒ(1S)decays

Author

Thomas Ferguson, B. Gittelman, I. J. Kim, R. S. Galik, Y. Kubota, F. Morrow, J. Whitmore, H. Kagan, Daniela Bortoletto, D. L. Hartill, W. M. Yao, V. Sharma, R. Ehrlich, J. W. Dewire, A. Jawahery, A. M. Halling, R. Poling, W. C. Li, E. H. Thorndike, T. Copie, James Alexander, M. Worris, D. G. Cassel, D. L. Kreinick, M. Procario, T. Jensen, F. M. Pipkin, M. Pisharody, J. Byrd, L. Garren, Helmut Vogel, P. Lubrano, Karl Berkelman, A. J. Sadoff, S. Nandi, D. Xiao, Xinchou Lou, Themistocles Bowcock, Ian Shipsey, M. S. Alam, S. E. Csorna, C. Bebek, J. Dominick, Richard Wilson, M. Sapper, John Yelton, K. Sparks, W. Y. Chen, C. R. Ng, D. Perticone, D. Riley, Ian Brock, D. R. Johnson, R. Kowalewski, T. Skwarnicki, M. Hempstead, Persis S. Drell, A. Silverman, P. Haas, James Mueller, K. Kinoshita, C. H. Park, Marina Artuso, D. Besson, Philip Baringer, Elliott Cheu, H. Worden, Glen D. Crawford, N. B. Mistry, N. Horwitz, R. L. McIlwain, N. Katayama, D. M. Coffman, M. D. Mestayer, E. Blucher, B. K. Heltsley, R. Namjoshi, C. O'Grady, J. Kandaswamy, D. Peterson, R. Fulton, T. Letson, D. H. Miller, E. Nordberg, J. Wolinski, M. Goldberg, Ha Lam, Sheldon Stone, Paul Avery, J. D. Lewis, C. R. Sun, R. D. Kass, G. C. Moneti, E. I. Shibata, and S. W. Gray

Subjects
Physics, Crystallography, Particle physics, Angular distribution, Meson, Branching fraction, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Hadron, Radiative transfer, Elementary particle, Quarkonium, Boson
Abstract

We report on a study of exclusive radiative decays of the {Upsilon}(1{ital S}) resonance. We have considered decays into final states of the form {Upsilon}{r arrow}{gamma}{ital n}({ital h}{sup +}{ital h}{sup {minus}}), with ({ital h}{sup +}{ital h}{sup {minus}}) denoting a charged-hadron pair (either {pi}{sup +}{pi}{sup {minus}},{ital K}{sup +}{ital K}{sup {minus}}, or {ital p{bar p}}), and {ital n} denoting the number of such pairs in the event. We measure branching ratios for {ital n}=2, 3, and 4, and search for structure in the recoiling hadronic system. For the {ital n}=1 case, we present upper limits. No evidence is observed for two-body radiative decays of the {Upsilon}(1{ital S}) meson in any of the above channels.

Published
1990

11. P-wave charmed mesons ine+e−annihilation

Author

M. Procario, R. S. Galik, R. Fulton, Y. Kubota, D. Riley, L. Garren, J. K. Nelson, R. L. McIlwain, Ian Shipsey, E. Nordberg, A. Silverman, C. Bebek, C. H. Park, D. L. Hartill, S. F. Schaffner, Daniela Bortoletto, N. B. Mistry, R. Poling, Ha Lam, M. Hempstead, W. Y. Chen, H. Worden, K. Sparks, J. D. Lewis, G. C. Moneti, D. G. Cassel, C. R. Ng, M. Sapper, J. W. Dewire, C. R. Sun, E. I. Shibata, R. D. Kass, Richard Wilson, C. O'Grady, F. Morrow, E. H. Thorndike, Marina Artuso, F. M. Pipkin, M. Pisharody, Karl Berkelman, N. Katayama, M. S. Alam, James Alexander, J. Kandaswamy, A. M. Halling, N. Horwitz, Themistocles Bowcock, R. Namjoshi, D. M. Coffman, Sheldon Stone, W. C. Li, S. Nandi, Paul Avery, M. D. Mestayer, T. Jensen, M. Worris, Persis S. Drell, D. Peterson, B. K. Heltsley, J. Whitmore, T. Letson, D. H. Miller, B. Gittelman, J. Wolinski, Xinchou Lou, S. E. Csorna, D. Besson, I. J. Kim, K. Kinoshita, D. R. Johnson, M. Goldberg, A. Jawahery, R. Ammar, V. Sharma, R. Ehrlich, H. Kagan, D. L. Kreinick, T. Skwarnicki, J. Dominick, D. Xiao, A. J. Sadoff, D. Perticone, Elliott Cheu, Glen D. Crawford, P. Haas, James Mueller, Philip Baringer, John Yelton, W. M. Yao, and S. W. Gray

Subjects
Physics, Particle physics, Annihilation, Meson, Electron–positron annihilation, Mass spectrum, State (functional analysis), Cornell Electron Storage Ring
Abstract

Author(s): Avery, P; Besson, D; Garren, L; Yelton, J; Bowcock, T; Kinoshita, K; Pipkin, FM; Procario, M; Wilson, R; Wolinski, J; Xiao, D; Ammar, R; Baringer, P; Haas, P; Lam, H; Jawahery, A; Park, CH; Nelson, JK; Perticone, D; Poling, R; Chen, W; Dominick, J; McIlwain, RL; Miller, DH; Ng, CR; Schaffner, SF; Shibata, EI; Yao, W; Sparks, K; Thorndike, EH; Alam, MS; Kim, IJ; Li, WC; Lou, XC; Sun, CR; Fulton, R; Hempstead, M; Jensen, T; Johnson, DR; Kagan, H; Kass, R; Morrow, F; Whitmore, J; Bortoletto, D; Goldberg, M; Horwitz, N; Mestayer, MD; Moneti, GC; Sharma, V; Shipsey, IP; Skwarnicki, T; Csorna, SE; Letson, T; Alexander, J; Artuso, M; Bebek, C; Berkelman, K; Cassel, DG; Cheu, E; Coffman, DM; Crawford, G; DeWire, JW; Drell, PS; Ehrlich, R | Abstract: Using the CLEO detector at the Cornell Electron Storage Ring, we have found evidence for L=1 charmed mesons in e+e- annihilations. We observe a D**0 state at mass 2461±3±1 MeV/c2 and width 20-12-10+9+9 MeV/c2 decaying to D+-. We also see an enhancement in the m(D*+-)-m(D*+) mass-difference spectrum and by examining D*+ decay-angle dependence, we see structure consistent with two states decaying to D*+-. We observe a lower-mass state, at mass (2428±3±2) MeV/c2 and width (23-6-4+8+10) MeV/c2, assuming that the higher-mass component is from the decay D**0(2461)D*+-. We present arguments for the spin-parity assignments of these states. We also report observation of candidate L=1 cs» state decaying to D*+Ks0. © 1990 The American Physical Society.

Published
1990

12. Observation ofB-meson semileptonic decays to noncharmed final states

Author

W. M. Yao, J. D. Lewis, M. Thulasidas, H. Kagan, A. M. Halling, M. Procario, R. Ehrlich, James Mueller, D. L. Kreinick, C. Bebek, Philip Baringer, A. J. Sadoff, M. Worris, Pu Wang, Cong Wang, R. Fulton, Daniela Bortoletto, Ian Shipsey, D. Z. Besson, J. Kandaswamy, D. R. Johnson, K. Sparks, John Yelton, J. W. Dewire, Xinchou Lou, D. G. Cassel, R. Ammar, T. Letson, D. M. Coffman, D. L. Hartill, E. I. Shibata, D. Peterson, R. Namjoshi, B. K. Heltsley, Ha Lam, C. R. Ng, P. S. Drell, W. Y. Chen, S. W. Gray, A. Silverman, Marina Artuso, Thomas Ferguson, R. Poling, E. Nordberg, P. Wilson, Elliott Cheu, N. Horwitz, J. Whitmore, L. Garren, D. Perticone, M. Hempstead, Glen D. Crawford, Vipul Jain, B. Gittelman, C. H. Park, T. Jensen, Janice Nelson, M. Sapper, I. J. Kim, N. B. Mistry, J. Wolinski, H. Worden, A. Jawahery, M. Pisharody, Karl Berkelman, Soumitra Nandi, C. O'Grady, C. R. Sun, R. D. Kass, Sheldon Stone, Paul Avery, M. D. Mestayer, E. H. Thorndike, F. M. Pipkin, T. J. V. Bowcock, D. Coppage, R. L. McIlwain, R. S. Galik, M. S. Alam, P. Haas, N. Katayama, T. Skwarnicki, M. Goldberg, G. C. Moneti, Vivek Sharma, S.F. Schaffner, Wei Li, D. H. Miller, J. Alexander, Richard Wilson, F. Morrow, D. Xiao, S. E. Csorna, M. I. Zoeller, K. Kinoshita, D. Riley, I. C. Brock, and Yuichi Kubota

Subjects
Semileptonic decay, Physics, Particle decay, Particle physics, Meson, Branching fraction, Electron–positron annihilation, Hadron, General Physics and Astronomy, B meson, Quarkonium
Abstract

We report the first evidence of charmless semileptonic decays of {ital B} mesons. In the momentum interval 2.4--2.6 GeV/{ital c} where the background from {ital b}{r arrow}{ital cl}{nu} is negligible, the average of the measured {ital b}{r arrow}{ital ue}{nu} and {ital b}{r arrow}{ital u}{mu}{nu} partial branching ratios is {Delta}{ital B}{sub {ital ub}}(2.4,2.6) =(1.8{plus minus}0.4{plus minus}0.3){times}10{sup {minus}4}. Inclusion of data from the interval 2.2--2.4 GeV/{ital c}, where the lepton yield is dominated by {ital b}{r arrow}{ital cl}{nu}, gives {Delta}{ital B}{sub {ital ub}}(2.2,2.6) =(3.3{plus minus}0.8{plus minus}0.8){times}10{sup {minus}4}. {vert bar}{ital V}{sub {ital ub}}/V{sub cb}{vert bar} depends on the theoretical model of {ital b}{r arrow}{ital ul}{nu} decay and is approximately 0.1.

Published
1990

13. Proposal for an Er/sup 3+/-doped chalcogenide glass fiber upconversion laser operating at 980 nm and pumped at 1480 nm

Author

David N. Payne, C.C. Ye, M. Hempstead, and Daniel W. Hewak

Subjects
Optical amplifier, Materials science, business.industry, chemistry.chemical_element, Chalcogenide glass, Population inversion, Laser, Atomic and Molecular Physics, and Optics, Photon upconversion, Electronic, Optical and Magnetic Materials, law.invention, Optical pumping, Erbium, Optics, chemistry, law, Optoelectronics, Electrical and Electronic Engineering, business, Lasing threshold
Abstract

We propose a novel fiber upconversion laser operating at 980 nm and pumped at 1480 nm, which will allow remote optical pumping of erbium-doped optical amplifiers. From the measured spectroscopy, we show Er3+-doped gallium lanthanum sulphide glass to be a potential host for such a 1480nm/980nm upconversion laser. The small-signal gain is analyzed numerically and the lasing possibilities are discussed.

Published
1997

14. Strong photo-induced refractive index changes in RF-sputtered tantalum oxide planar waveguides

Author

Jean-Luc Archambault, Liang Dong, M. Hempstead, M.P. Roe, and P. St. J. Russell

Subjects
Optical fiber, Materials science, Silicon photonics, business.industry, Microstructured optical fiber, Graded-index fiber, Waveguide (optics), law.invention, Slot-waveguide, Optics, Planar, law, Optoelectronics, sense organs, skin and connective tissue diseases, business, Refractive index
Abstract

Optical waveguide gratings have a multitude of uses in laser, communications, and sensing systems, in both planar and fibre configurations. They may be fabricated holographically in materials that display high levels of photosensitivity when exposed to UV light. An example is Bragg grating formation in germano-silicate optical glass fibres1 and planar waveguides of similar composition.2 We report here, for the first time, strong UV-induced refractive index changes in sputtered tantalum oxide planar waveguides.

Published
2005

15. Non-photorefractive CW Tm-indiffused Ti:LiNbO3 waveguide laser operating at room temperature

Author

Anne C. Tropper, J.K. Jones, Ji Wang, J.P. de Sandro, M. Hempstead, and David Shepherd

Subjects
Materials science, business.industry, chemistry.chemical_element, Laser pumping, Photorefractive effect, Laser, Waveguide (optics), Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, law.invention, Thulium, Optics, chemistry, law, Optoelectronics, Laser power scaling, Electrical and Electronic Engineering, business, Lasing threshold, Tunable laser
Abstract

We report laser operation at 1.81 /spl mu/m and 1.85 /spl mu/m in a Tm/sup 3+/:LiNbO/sub 3/ Ti-diffused waveguide doped by thermal indiffusion at high temperature. We believe this is the first time lasing has been seen in Tm:LiNbO/sub 3/ at room temperature. Continuous-wave operation was achieved at room temperature with a threshold of 42 mW launched pump power. The output power was observed to be stable, without any sign of photorefractive damage.

Published
1996

16. Four-wave mixing in EDFAs

Author

Stephen P. Hegarty, R.S. Mozdy, Yanming Liu, R.G. Smart, S. Burtsev, and M. Hempstead

Subjects
Physics, Four-wave mixing, Multi-mode optical fiber, Optics, business.industry, Cross-phase modulation, Physics::Optics, Dispersion-shifted fiber, Channel spacing, Polarization-maintaining optical fiber, Plastic optical fiber, business, Graded-index fiber
Abstract

We study FWM in C- and L-band EDFAs. We observe that FWM efficiency is determined by fiber length and channel spacing. We show that FWM from EDFAs exceeds that from non-zero dispersion-shifted fiber in DWDM system.

Published
2002

17. Ablated gratings on borosilicate glass by 193nm excimer laser radiation

Author

M. N. Zervas, Stavros Pissadakis, Laurence Reekie, James S. Wilkinson, and M. Hempstead

Subjects
Distributed feedback laser, Fabrication, Materials science, Excimer laser, Borosilicate glass, business.industry, medicine.medical_treatment, Physics::Optics, General Chemistry, Photorefractive effect, Waveguide (optics), X-ray laser, Optics, medicine, General Materials Science, Physics::Atomic Physics, Photonics, business
Abstract

The application of 193nm ArF excimer laser radiation to the fabrication of high-quality sub-micron relief gratings in Er/Yb-doped borosilicate glass using an interferometric system is presented. High quality relief gratings imprinted in silicate telecom glasses may find significant application in optical telecommunications or photonic band-gap fields in the near future. In particular, relief gratings applied to fibre or waveguide devices may provide high diffraction efficiencies over reduced dimensions compared with photorefractive gratings. Their straightforward application to a wide range of materials and the single step imprinting process are additional advantages. The ablation of BK-7 borosilicate glass using 193nm excimer laser radiation produces high quality surface etching when compared to 248nm radiation, prompting the use of this shorter wavelength for the fabrication of high-quality sub-micron structures.

Published
1999

18. Photonic Crystals in Planar Waveguides

Author

D.M. Atkin, P.S.J. Russell, and M. Hempstead

Subjects
Waveguide (electromagnetism), Materials science, Guided-mode resonance, business.industry, Photonic integrated circuit, Physics::Optics, Microstructured optical fiber, Grating, Yablonovite, Planar, Optics, Optoelectronics, business, Nonlinear Sciences::Pattern Formation and Solitons, Photonic crystal
Abstract

In this thesis the properties of waveguide modes in photonic crystal planar waveguides are considered. These are waveguides that have been etched with multi-dimensional gratings to create new wavelength dispersive and spatially dispersive behaviours. Analytical models have been developed for the modes in one and two-dimensional photonic crystal waveguides. These describe many of the rich phenomena that may be observed. Weak two-dimensional photonic crystal planar waveguides have been fabricated and their properties have been measured with a specially developed conical prism coupling technique. This thesis demonstrates the advantages of combining photonic crystals with planar waveguides. While future lithographic systems will have sufficient resolution to incorporate photonic crystal regions in integrated optical devices, it has been shown that the waveguide geometry increases the actual grating period required for optical band gaps and so lessens technological difficulties. It is also shown that there are stationary modes which could act as microresonators and that ranges of modes can be suppressed in multimode waveguides. Prism coupling has demonstrated the strong dispersive and frequency selective behaviour of weak photonic crystal waveguides. The future application of this work to efficient, broadband, nonlinear wavelength conversion is proposed.

Published
1998

19. Ion-exchanged glass waveguide lasers and amplifiers

Author

M Hempstead

Subjects
Materials science, Optical fiber, business.industry, Amplifier, Physics::Optics, chemistry.chemical_element, Laser, Waveguide (optics), law.invention, Ion, Glass waveguide, Erbium, Optics, chemistry, law, Fiber laser, Optoelectronics, business
Abstract

In this paper I will survey the field of ion-exchanged glass waveguide lasers and amplifiers. Ion-exchanged waveguide devices have significant virtues, such as low propagation losses and suitability for mass production. The progress in realising lasers and amplifiers has been impressive, but more work is needed to produce commercially viable devices.

Published
1997

20. Spectroscopy and Optical Amplification in Cr doped LiNbO3

Author

J. Amin, James S. Wilkinson, José M. M. M. de Almeida, M. Hempstead, R.M. De La Rue, Charles N. Ironside, and Andreia Leite

Subjects
Waveguide lasers, chemistry.chemical_compound, Materials science, chemistry, Lithium niobate, Analytical chemistry, Cr doped, Material system, Spectroscopy, Absorption (electromagnetic radiation), Waveguide (optics)
Abstract

We present measured polarised absorption and emission cross-sections for Cr:LiNbO3, and investigate the feasibility of active waveguide devices in this material system.

Published
1996

21. Spectroscopic analysis of Er3+ transitions in lithium niobate

Author

T. Schweizer, M. Hempstead, Bernard Dussardier, J. Amin, Optoelectronic Research Centre, University of Southampton, Laboratoire de physique de la matière condensée (LPMC), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)

Subjects
010302 applied physics, spectroscopy, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Absorption spectroscopy, Lithium niobate, Biophysics, 02 engineering and technology, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Biochemistry, Atomic and Molecular Physics, and Optics, Er-doped LiNb03, chemistry.chemical_compound, chemistry, Excited state, 0103 physical sciences, Atomic physics, 0210 nano-technology, Ground state, Spectroscopy, Crystal anisotropy, Line (formation)
Abstract

International audience; We report on the results of a spectroscopic analysis of the transition strengths of Er-doped LiNb03. The line strengths of several transitions from the ground state to excited state manifolds are evaluated from measured polarised absorption spectra and analysed using Judd-Ofelt theory, taking into account the crystal anisotropy. The measured and calculated oscillator strengths at 300 K compare favourably within the typical uncertainties associated with the Judd-Ofelt theory. The Judd-Ofelt parameters obtained have been used to evaluate the excited-state-absorption (ESA) transition strengths from the 4111,~level, which have important implications for pumping Er: LiNb03 devices.

Published
1996

22. Ion-exchanged Er/Yb waveguide laser at 1.5µm pumped by a laser diode

Author

P. Camy, James S. Wilkinson, C. Lerminiaux, J.E. Román, William S. Brocklesby, M. Hempstead, A. Béguin, and S. Nouh

Subjects
Optical fiber, Materials science, Laser diode, business.industry, Slope efficiency, Laser, Waveguide (optics), Ion, law.invention, Optics, law, Fiber laser, Optoelectronics, Electrical and Electronic Engineering, business, Lasing threshold
Abstract

A diode-pumped planar Er/Yb waveguide laser is demonstrated. The device was fabricated by thallium exchange in a phosphorus-free silicate glass. Lasing was achieved at 1544 nm with a threshold of 5 mW and a slope efficiency of 2%. The low threshold indicates the absence of the severe backtransfer effects previously reported in Er/Yb bulk laser silicate glasses.

Published
1995

23. 1.7 micron excited state absorption measurement in erbium-doped glasses

Author

Salim Nouh, Patrice Camy, M. Hempstead, Christian Lerminiaux, Chenchun Ye, J.E. Román, and Pascale Laborde

Subjects
Range (particle radiation), Materials science, Physics and Astronomy (miscellaneous), Absorption spectroscopy, Doping, Analytical chemistry, chemistry.chemical_element, Infrared spectroscopy, Spectral line, Photon upconversion, law.invention, Erbium, chemistry, law, Atomic physics, Waveguide
Abstract

We have measured, for the first time, the complete 1.7µm excited state absorption spectrum in erbium doped glasses. The spectrum is obtained by measuring the gain of an erbium doped waveguide in the 1400-1800 nm region. Using the measured spectra, we estimate the 1.5µm uniform upconversion rate by calculating the spectral overlap between the 1.5µm emission and 1.7µm ESA cross sections. The technique is applied to erbium-doped, ion-exchangeable silicate glasses, yielding upconversion constants in the range of 1-10 x 10-18 cm3 /s.

Published
1995

24. Lossless integrated active splitters for optical networks

Author

F.W. Willems, A.M.J. Koonen, M. Hempstead, J.C. van der Plaats, J.E. Román, P. Laborde, A. Béguin, Patrice Camy, R. Ries, and Christian Lerminiaux

Subjects
Optical amplifier, Lossless compression, Materials science, Amplifier, Optical engineering, Splitter, Optical cross-connect, Electronic engineering, Fiber optic splitter, media_common.cataloged_instance, European union, media_common
Abstract

We discuss the latest results in the European Union RACE II project LIASON to specify and develop "lossless" splitters in integrated optics, combining an erbium-doped planar amplifier and a passive 1xN cascaded y-junction splitter.

Published
1995

25. The photoluminescence of erbium-doped silicon monoxide

Author

G J Parker, S W Roberts, and M Hempstead

Subjects
Photoluminescence, Materials science, Annealing (metallurgy), business.industry, Organic Chemistry, Doping, chemistry.chemical_element, Silicon monoxide, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Inorganic Chemistry, Erbium, chemistry.chemical_compound, Wavelength, chemistry, Optoelectronics, Photoluminescence excitation, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, business, Spectroscopy
Abstract

Films of silicon monoxide coevaporated with erbium are shown to produce strong room temperature photoluminescence peaked at 1535 nm after annealing at 600°C. Decay measurements show a double exponential function with lifetimes of 0.41 ms and 2.12 ms, suggesting two distinct optically active erbium sites. Photoluminescence excitation spectroscopy between 700 and 860 nm reveals a monotonic increase in photoluminescence intensity towards shorter wavelengths. This result suggests that the transfer of energy from the pump source to the erbium ions is mainly via the recombination of electron-hole pairs (photocarriers) which are created by absorption within the SiO.

Published
1995

26. Ion-exchanged waveguide amplifier in erbium-doped glass for broad-band communications

Author

J.E. Román, Patrice Camy, Christian Lerminiaux, M. Hempstead, and Pascale Laborde

Subjects
Materials science, Fabrication, business.industry, Amplifier, Doping, Electrical engineering, Broad band, chemistry.chemical_element, Physics::Optics, Condensed Matter::Disordered Systems and Neural Networks, Ion, Erbium, Planar, Waveguide amplifier, chemistry, Condensed Matter::Superconductivity, Optoelectronics, Condensed Matter::Strongly Correlated Electrons, business
Abstract

We discuss the fabrication, characterisation and modelling of planar erbium-doped amplifiers realised as ion-exchanged waveguides in glass.

Published
1995

27. Spectra and Energy Levels of the Trivalent Ytterbium Ion Doped into Lithium Niobate by Thermal Indiffusion

Author

M. Hempstead, J.K. Jones, Anne C. Tropper, J.P. de Sandro, David Shepherd, and James S. Wilkinson

Subjects
Ytterbium, Materials science, Dopant, business.industry, Lithium niobate, Doping, Analytical chemistry, chemistry.chemical_element, Thermal diffusivity, Laser, Ion, law.invention, chemistry.chemical_compound, chemistry, law, Optoelectronics, business, Absorption (electromagnetic radiation)
Abstract

An X-cut LiNbO3 substrate has been doped with Yb3+ ions by thermal diffusion from an Yb metal film of thickness 7nm. Polarised absorption and fluorescence spectra of the dopant ion have been measured using Ti-diffused y-propagating channel waveguides prepared in the doped region. Yb is a diode pumpable laser ion with characteristics that can be compared favourably with those of Nd in some respects; for example the small energy difference between pump and laser photons reduces thermal load facilitating high power operation. A waveguide laser geometry is particularly advantageous for Yb due to the quasi-3-level nature of the laser transition. The simple fabrication technique described here has been used to produce a system which may have the potential to operate as an Yb waveguide laser in an electro-optic host crystal.

Published
1993

28. Integrated Q-switched multiple-cavity glass waveguide laser

Author

Laurence Reekie, E.K. Mwarania, M. Hempstead, James S. Wilkinson, and D.M. Murphy

Subjects
Optical amplifier, Distributed feedback laser, Materials science, business.industry, Physics::Optics, Waveguide (optics), Q-switching, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, law.invention, Resonator, Optics, Mode-locking, law, Optical cavity, Laser power scaling, Electrical and Electronic Engineering, business
Abstract

A novel Q-switching scheme, using rapid variation of the path difference between the cavities of a multiple-cavity resonator, is described. A thermooptic phase modulator was used to switch the cavity loss of a Y-junction glass waveguide laser between high and low states. Q-switched pulses with durations of 5 mu s and peak powers of 70 mW were obtained. >

Published
1992

29. A measurement of the refractive index of sodium fluoride in the far ultraviolet

Author

M. Hempstead, T. Ypsilantis, G. Comby, J. Seguinot, J. Chauveau, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, business.industry, Far ultraviolet, 01 natural sciences, Wavelength, chemistry.chemical_compound, Optics, chemistry, 0103 physical sciences, Sodium fluoride, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010306 general physics, business, Instrumentation, Refractive index
Abstract

We describe the measurement of the refractive index of sodium fluoride in the far ultraviolet, from 145 to 245 nm. We find the refractive index at short wavelengths to be significantly different from prediction.

Published
1991

30. Electric-field-induced periodic domain inversion in Nd3+-diffused LiNbO3

Author

James S. Wilkinson, J. Webjörn, P. St. J. Russell, J. Amin, and M. Hempstead

Subjects
Materials science, Field (physics), business.industry, Poling, Doping, Lithium niobate, chemistry.chemical_element, Isotropic etching, Neodymium, chemistry.chemical_compound, Optics, chemistry, Periodic poling, Electric field, Electrical and Electronic Engineering, business
Abstract

The authors report the first demonstration of electric-field-induced periodic poling in neodymium-indiffused lithium niobate. The fidelity of patterning is as good as with undoped samples, and the poling field required is smaller. This novel combination of two techniques for manipulation of the optical properties of lithium niobate makes possible an extended range of active devices.

Published
1994

31. Four-wave mixing in EDFAs

Author

M. Hempstead, R.S. Mozdy, Y. Liu, G.G. Luther, S. Tsuda, Stephen P. Hegarty, R.G. Smart, and S. Burtsev

Subjects
Optical amplifier, L band, Materials science, C band, business.industry, chemistry.chemical_element, Erbium, Crosstalk, Four-wave mixing, Optics, chemistry, Wavelength-division multiplexing, Electrical and Electronic Engineering, business
Abstract

A study is presented of four-wave mixing (FWM) in L- and C-band EDFAs. From experiments, it has been observed that FWM scales with the length of Er-doped fibre. It is shown theoretically that FWM crosstalk from EDFAs considerably exceeds that from NZDSF fibre in DWDM L-band systems and leads to a penalty of up to 1 dB in terms of the Q parameter.

Published
1999

32. Ion-exchanged planar lossless splitter at 1.5 [micro sign]m

Author

J.E. Román, J.C. van der Plaats, James S. Wilkinson, P. Camy, C. Prel, M. Hempstead, A.M.J. Koonen, A. Béguin, C. Lerminiaux, and F.W. Willems

Subjects
Ytterbium, Materials science, Laser diode, business.industry, Borosilicate glass, chemistry.chemical_element, Ion, law.invention, Optical pumping, Erbium, Planar, Optics, chemistry, law, Splitter, Electrical and Electronic Engineering, business
Abstract

The authors demonstrate the first ion-exchanged, planar lossless splitter at 1.5 /spl mu/m. The 1/spl times/2 device was fabricated by thallium ion exchange in an Er/Yb codoped borosilicate glass and achieved lossless splitting over the wavelength range 1534-1548 nm when pumped with a 980 nm laser diode.

Published
1996

33. Tunable coupled-cavity waveguide laser at room temperature in Nd-diffused Ti:LiNbO_3

Author

J.E. Román, James S. Wilkinson, J. Amin, and M. Hempstead

Subjects
Amplified spontaneous emission, Materials science, business.industry, Slope efficiency, Atmospheric temperature range, Laser, Waveguide (optics), Atomic and Molecular Physics, and Optics, law.invention, Optical pumping, Wavelength, Optics, law, Optoelectronics, business, Lasing threshold
Abstract

We report on a Y-junction channel waveguide laser, operating at room temperature, in Nd-diffused Ti:LiNbO(3). Pumping was performed with a cw Ti:A1(2)O(3) laser operating at 816 nm. With feedback provided only by the polished end faces of the device, a cw lasing threshold of ~39-mW launched pump power was obtained, with a slope efficiency of ~35%. Using 95% reflectivity mirrors at the waveguide ends, we reduced the lasing threshold to ~4 mW, with a slope efficiency of ~2.6%. Tuning of the lasing signal over a range of 2.3 nm around a center wavelength of 1092.7 nm was demonstrated, with a monolithically integrated phase modulator.

Published
1994

34. Limit on the mass of the tau neutrino

Author

Harris Kagan, Paul Tipton, M. S. Alam, Richard Wilson, C. Bebek, Ron Poling, S. E. Csorna, I. J. Kim, Sheldon Stone, A. M. Halling, Paul Avery, Ian Brock, R. Kowalewski, Chih-Ree Sun, Themistocles Bowcock, P. Haas, James Mueller, D. L. Kreinick, R. DeSalvo, K. Kinoshita, A. Chen, D. Perticone, J. Hassard, T. Jensen, N. B. Mistry, S. Holzner, S. Behrends, M. Pisharody, A. Silverman, G. C. Moneti, Karl Berkelman, M. D. Mestayer, D. Riley, V. Sharma, R. Ehrlich, T. Copie, C. Rippich, M. Goldberg, B. K. Heltsley, Kenneth Francis Read, A. Engler, R. D. Kass, M. Hempstead, Hans J. Vogel, Xia Yi, Joan A. Guida, J. Kandaswamy, N. Katayama, S. W. Gray, L. Garren, R. W. Kraemer, M. Ito, J. Wolinski, E. Nordberg, D. Peterson, P. Lubrano, R. Holmes, N. Horwitz, M. Ogg, Alice Bean, G. B. Word, R. T. Giles, F. Morrow, R. S. Panvini, G. J. Bobbink, E. H. Thorndike, F. M. Pipkin, D. L. Hartill, V. Tanikella, E. Blucher, R. Namjoshi, A. Jawahery, T. Gentile, D. Xiao, D. Besson, D. G. Cassel, Murdock Gilchriese, B. Gittelman, A. J. Sadoff, R. S. Galik, Daniela Bortoletto, Y. Kubota, Thomas Ferguson, J. W. Dewire, and Jan M. Guida

Subjects
Nuclear physics, Massless particle, Physics, Particle decay, Particle physics, Annihilation, Tau neutrino, High Energy Physics::Experiment, Elementary particle, Limit (mathematics), Neutrino, Lepton
Abstract

We place an upper limit on the mass of the tau neutrino by using the total-charged-energy distribution in three-track tau decays. Including both statistical and systematic uncertainties, the 95%-confidence-level limit is m/sub ..nu../

Published
1987

35. Measurement of theϒmass

Author

R. T. Giles, M. Hempstead, J. Hassard, Richard Wilson, L. N. Hand, K. Kinoshita, F. M. Pipkin, and W. W. MacKay

Subjects
Nuclear physics, Physics, Antiparticle, Meson, CLEO, Electron–positron annihilation, Antimatter, Hadron, CUSB, Atomic physics, Cornell Electron Storage Ring
Abstract

We have detected the polarization of the positron beam in the Cornell Electron Storage Ring (CESR) with a polarimeter which detects back-scattered laser light. The beam was resonantly depolarized using a vertical shaker magnet with a rf field, thus measuring the $g\ensuremath{-}2$ frequency. This gave us a precise value for the beam energy in CESR. By scanning the $\ensuremath{\Upsilon}$ resonance with the CUSB detector, we obtained a mass ${M}_{\ensuremath{\Upsilon}}=9459.97\ifmmode\pm\else\textpm\fi{}0.11\ifmmode\pm\else\textpm\fi{}0.07$ MeV. We also give rescaled values for the excited $\ensuremath{\Upsilon}$ states.

Published
1984

36. Measurement of the muonic branching fractions of the Υ(1S) and Υ(3S)

Author

C. O'Grady, M. Procario, N. Horwitz, Tomasz Skwarnicki, L. Garren, A. Silverman, D. L. Hartill, R. Poling, Ha Lam, W. M. Yao, D. Besson, E. H. Thorndike, F. M. Pipkin, M. Sapper, C. Bebek, T. Letson, D. H. Miller, Richard Wilson, W. Y. Chen, M. S. Alam, Sheldon Stone, John Yelton, Paul Avery, M. Pisharody, F. Morrow, Karl Berkelman, H. Worden, Thomas Ferguson, M. Goldberg, J. Kandaswamy, W. C. Li, Persis S. Drell, T. Jensen, D. Peterson, D. M. Coffman, B. K. Heltsley, R. Fulton, D. Xiao, S. Nandi, A. M. Halling, J. D. Lewis, J. Wolinski, D. Riley, Elliott Cheu, Ian Brock, M. Worris, Glen D. Crawford, E. Blucher, D. L. Kreinick, M. D. Mestayer, H. Kagan, R. Kowalewski, C. R. Sun, S. W. Gray, R. L. McIlwain, R. D. Kass, M. Hempstead, Themistocles Bowcock, R. Namjoshi, S. E. Csorna, J. Byrd, C. H. Park, A. J. Sadoff, D. R. Johnson, N. B. Mistry, Xinchou Lou, K. Kinoshita, D. G. Cassel, N. Katayama, E. Nordberg, A. Jawahery, C. R. Ng, Marina Artuso, Daniela Bortoletto, J. W. Dewire, V. Sharma, B. Gittelman, R. Ehrlich, I. J. Kim, D. Perticone, R. S. Galik, Y. Kubota, J. Whitmore, P. Haas, James Mueller, Philip Baringer, R. DeSalvo, G. C. Moneti, E. I. Shibata, and Ian Shipsey

Subjects
Physics, Analytical chemistry, Atomic physics, Cornell Electron Storage Ring
Abstract

Author(s): Chen, W; McIlwain, RL; Miller, DH; Ng, CR; Shibata, EI; Yao, W; Thorndike, EH; Alam, MS; Katayama, N; Kim, IJ; Li, WC; Lou, XC; Sun, CR; Bortoletto, D; Goldberg, M; Horwitz, N; Mestayer, MD; Moneti, GC; Sharma, V; Shipsey, IP; Skwarnicki, T; Csorna, SE; Letson, T; Brock, IC; Ferguson, T; Artuso, M; Bebek, C; Berkelman, K; Blucher, E; Byrd, J; Cassel, DG; Cheu, E; Coffman, DM; Crawford, G; DeSalvo, R; DeWire, JW; Drell, PS; Ehrlich, R; Galik, RS; Gittelman, B; Gray, SW; Halling, AM; Hartill, DL; Heltsley, BK; Kandaswamy, J; Kowalewski, R; Kreinick, DL; Kubota, Y; Lewis, JD; Mistry, NB; Mueller, J; Namjoshi, R; Nandi, S; Nordberg, E; O'Grady, C; Peterson, D; Pisharody, M; Riley, D; Sapper, M; Silverman, A; Stone, S; Worden, H; Worris, M; Sadoff, AJ | Abstract: Using the CLEO detector at the Cornell Electron Storage Ring, we have measured the muonic branching fractions B of the (1S) and (3S) to be (2.520.070.07)% and (2.020.190.33)%, respectively. © 1989 The American Physical Society.

Published
1989

37. Study ofπ+π−transitions from the Υ(3S)

Author

D. Perticone, S. Holzner, S. Behrends, Jan M. Guida, D. L. Hartill, R. W. Kraemer, T. Copie, R. Ehrlich, A. Jawahery, N. Horwitz, E. Nordberg, Thomas Ferguson, B. K. Heltsley, D. G. Cassel, R. Desalvo, A. Engler, V. Tanikella, C. Rippich, Kenneth Francis Read, Hans J. Vogel, D. Z. Besson, M. Hempstead, R. Poling, D. L. Kreinick, C. Bebek, T. Gentile, H. Kagan, Murdock Gilchriese, Paul Tipton, James Mueller, B. Gittelman, M. Ogg, P. Haas, G.J. Bobbink, I. J. Kim, A. J. Sadoff, Xia Yi, A. M. Halling, R. S. Panvini, J. Hassard, A. Silverman, M. Pisharody, T. Jensen, Karl Berkelman, E. H. Thorndike, M. Ito, Daniela Bortoletto, L. Garren, J. W. Dewire, F. M. Pipkin, Themistocles Bowcock, R. Kowalewski, J. Wolinski, A. Chen, F. Morrow, R. S. Galik, D. Xiao, N. B. Mistry, M. S. Alam, Joan A. Guida, J. Kandaswamy, M. Goldberg, G. C. Moneti, Vivek Sharma, D. Peterson, R. T. Giles, N. Katayama, M. D. Mestayer, R. Namjoshi, S. W. Gray, E. Blucher, P. Lubrano, R. Holmes, Alice Bean, S. E. Csorna, K. Kinoshita, D. Riley, G. B. Word, I. C. Brock, Yuichi Kubota, Richard Wilson, C. R. Sun, R. D. Kass, Sheldon Stone, and Paul Avery

Subjects
Nuclear physics, Physics, Particle physics, Electron–positron annihilation, Pi, General Physics and Astronomy
Published
1987

38. B0B¯0mixing at theΥ(4S)

Author

D. M. Coffman, B. K. Heltsley, J. Whitmore, D. L. Kreinick, C. Bebek, T. Jensen, H. Kagan, E. H. Thorndike, N. Horwitz, D. G. Cassel, W. Y. Chen, L. Garren, Ha Lam, Daniela Bortoletto, R. Poling, R. Kowalewski, F. M. Pipkin, J. W. Dewire, M. S. Alam, R. Desalvo, S. E. Csorna, J. Byrd, C. H. Park, A. M. Halling, M. Worris, A. J. Sadoff, P. S. Drell, K. Kinoshita, N. B. Mistry, Sheldon Stone, D. L. Hartill, Thomas Ferguson, Paul Avery, D. R. Johnson, M. Sapper, Xinchou Lou, E. Blucher, J. Wolinski, M. Pisharody, Karl Berkelman, J. Kandaswamy, C. O'Grady, B. Gittelman, I. J. Kim, R. S. Galik, Marina Artuso, M. Procario, D. Peterson, Tomasz Skwarnicki, A. Jawahery, T. J. V. Bowcock, Elliott Cheu, M. Hempstead, Glen D. Crawford, N. Katayama, E. I. Shibata, C. R. Sun, R. D. Kass, M. D. Mestayer, T. Letson, Wei Li, John Yelton, D. H. Miller, R. L. McIlwain, C. R. Ng, H. Worden, P. Lubrano, R. Fulton, P. Haas, M. Goldberg, E. Nordberg, G. C. Moneti, Vivek Sharma, W. M. Yao, J. D. Lewis, T. Copie, S. Nandi, F. Morrow, D. Riley, I. C. Brock, Yuichi Kubota, D. Xiao, Richard Wilson, A. Silverman, R. Namjoshi, S. W. Gray, James Mueller, Philip Baringer, D. Perticone, R. Ehrlich, I. P. J. Shipsey, and D. Z. Besson

Subjects
Semileptonic decay, Physics, Particle decay, Particle physics, Meson, Branching fraction, Hadron, General Physics and Astronomy, B meson, Quarkonium, Lepton
Abstract

We have measured B/sup 0/B-bar/sup 0/ mixing by observing like-sign dilepton events in UPSILON(4S) decay. Assuming that the semileptonic branching fractions of the charged and neutral B mesons are equal and that the UPSILON(4S) decays to B/sup +/B/sup -/ 55% of the time and to B/sup 0/B-bar/sup 0/ 45% of the time, we measure the mixing parameter r to be 0.19 +- 0.06 +- 0.06, where the first error is statistical and the second is systematic.

Published
1989

39. Ruling out exotic models of b quark decay

Author

A. Jawahery, Robert Stone, E. H. Thorndike, F. M. Pipkin, W. W. MacKay, M. Herzlinger, K. Chadwick, P. Ganci, C. Rosenfeld, A. Fridman, R. Wilcke, Murdock Gilchriese, J. Chauveau, T. Ferguson, G. Rucinski, D. G. Cassel, Harris Kagan, H. Van Hecke, J. Haggerty, G. Parkhurst, H. Kooy, A. Chen, G. C. Moneti, Ron Poling, P. Avery, F. Sannes, S. L. Olsen, Joseph Izen, B. Gittelman, P. Lipari, Karl Berkelman, R. Plunkett, S. Holzner, M. Ogg, R. Ehrlich, N. Horwitz, M. S. Alam, T. Gentile, D. Weber, M. Hempstead, M. Ito, R. S. Panvini, Richard Wilson, J. Rohlf, D. Herrup, J. Hassard, A. Silverman, R. G. Hicks, M. Goldberg, V. Kistiakowsky, F. Morrow, R. S. Galik, D. L. Kreinick, A. J. Sadoff, Y. Kubota, R. Perchonok, J. W. Dewire, Joan A. Guida, J. Kandaswamy, N. B. Mistry, A. Snyder, P. Skubic, P. C. Stein, S. E. Csorna, Sheldon Stone, R. D. Kass, E. Nordberg, M. Jibaly, D. L. Hartill, M. D. Mestayer, James C. Green, C. J. Bebek, A. C. Melissinos, and D. Andrews

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Muon, Energy Fraction, High Energy Physics::Phenomenology, Higgs boson, High Energy Physics::Experiment, Electron, Bottom quark, Lepton
Abstract

We consider three broad classes of nonstandard models for b quark decay: (1) b → llq with charged or neutral leptons of arbitrary flavor; (2) b → l q q ; and (3) b → qa − where a − is a Higgs boson or hyperpion. For these classes of models we have calculated the charged energy fraction and the inclusive yields of electrons, muons, protons, and lambdas. We demonstrate that these model predictions are inconsistent with CLEO measurements at the γ (4S).

Published
1983

40. Search forb→utransitions in exclusive hadronicB-meson decays

Author

D. L. Hartill, Elliott Cheu, M. Hempstead, Glen D. Crawford, H. Worden, E. Blucher, C. R. Ng, A. M. Halling, D. G. Cassel, D. L. Kreinick, C. Bebek, M. Worris, R. Fulton, R. Ehrlich, M. S. Alam, R. Poling, John Yelton, E. H. Thorndike, E. Nordberg, N. Horwitz, J. Whitmore, H. Kagan, F. M. Pipkin, A. Silverman, D. Z. Besson, Marina Artuso, C. O'Grady, M. Procario, P. S. Drell, D. R. Johnson, J. Byrd, R. S. Galik, Thomas Ferguson, W. M. Yao, T. Skwarnicki, M. D. Mestayer, A. J. Sadoff, J. D. Lewis, Daniela Bortoletto, Xinchou Lou, R. L. McIlwain, T. Jensen, A. Jawahery, J. W. Dewire, R. Desalvo, James Mueller, D. M. Coffman, M. Goldberg, B. K. Heltsley, Philip Baringer, W. Y. Chen, G. C. Moneti, T. Letson, Ha Lam, P. Haas, Vivek Sharma, B. Gittelman, M. Sapper, J. Kandaswamy, M. Pisharody, Karl Berkelman, I. J. Kim, Themistocles Bowcock, J. Wolinksi, D. Peterson, F. Morrow, E. I. Shibata, D. Xiao, N. Katayama, L. Garren, R. Kowalewski, C. H. Park, N. B. Mistry, R. Namjoshi, S. W. Gray, D. Perticone, S. E. Csorna, I. P. J. Shipsey, K. Kinoshita, Wei Li, D. H. Miller, Soumitra Nandi, D. Riley, I. C. Brock, Yuichi Kubota, Richard Wilson, C. R. Sun, R. D. Kass, Sheldon Stone, and Paul Avery

Subjects
Physics, Particle physics, Meson, Branching fraction, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, General Physics and Astronomy, Elementary particle, Nuclear physics, Particle decay, Pion, High Energy Physics::Experiment, B meson
Abstract

From a data sample of 242 000 BB\ifmmode\bar\else\textasciimacron\fi{} pairs collected with the CLEO detector at the \ensuremath{\Upsilon}(4S) resonance, we set upper limits for the branching ratios for exclusive hadronic decays of B mesons arising from b\ensuremath{\rightarrow}u transitions. Model-dependent limits for the ratio of the Kobayashi-Maskawa matrix elements ${V}_{\mathrm{ub}}$/${V}_{\mathrm{cb}}$ are presented.

Published
1989

41. Measurement of the Leptonic Branching Ratios of theϒ(1S),ϒ(2S), andϒ(3S)

Author

G. C. Moneti, D. Andrews, D. G. Cassel, Karl Berkelman, Sheldon Stone, N. B. Mistry, J. W. Dewire, S. Holzner, S. Behrends, M. D. Mestayer, C. J. Bebek, Y. Kubota, G. Parkhurst, E. H. Thorndike, M. Ogg, R. S. Panvini, K. Chadwick, W. W. MacKay, P. Ganci, F. M. Pipkin, A. Fridman, D. L. Kreinick, Jan M. Guida, Richard Wilson, J. Chauveau, Joan A. Guida, J. Kandaswamy, Ron Poling, T. Gentile, M. Halling, P. Lipari, L. Garren, F. Morrow, R. Wilcke, R. Plunkett, R. Ehrlich, D. Peterson, Robert Stone, R. Galik, M. Ito, Murdock Gilchriese, A. Snyder, B. Gittelman, R. T. Giles, N. Horwitz, M. Goldberg, M. S. Alam, R. D. Kass, C. Rosenfeld, M. Hempstead, D. Weber, T. Ferguson, D. L. Hartill, V. Kistiakowsky, A. Chen, R. Perchonok, C. G. Trahern, S. L. Olsen, G. Rucinski, F. Sannes, J. Hassard, A. Silverman, P. C. Stein, S. E. Csorna, A. Jawahery, D. Herrup, H. Kagan, J. Rohlf, James C. Green, P. Avery, K. Kinoshita, A. J. Sadoff, Joseph Izen, R. G. Hicks, A. C. Melissinos, E. Nordberg, M. Jibaly, H. Van Hecke, and P. Skubic

Subjects
Nuclear physics, Physics, Particle physics, Particle decay, Muon, Meson, Branching fraction, Electron–positron annihilation, Hadron, General Physics and Astronomy, Cornell Electron Storage Ring, Lepton
Abstract

Using the CLEO detector at the Cornell Electron Storage Ring, the authors have measured the leptonic branching fraction, B/sub mumu/, of the UPSILON(1S), UPSILON(2S), and UPSILON(3S) to be 2.7 +- 0.3 +- 0.3%, 1.9 +- 1.3 +- 0.5%, and 3.3 +- 1.3 +- 0.7%, respectively. Combining these values of B/sub mumu/ with previous measurements of the leptonic widths of these resonances, the authors find the total width of the UPSILON(1S), UPSILON(2S), and UPSILON(3S) to be 48 +- 4 +- 4, 27 +- 17 +- 6, and 13 +- 4 +- 3 keV.

Published
1983

42. Measurement of Ds decay modes

Author

D. G. Cassel, B. Gittelman, H. Kagan, R. Fulton, W. M. Yao, E. Nordberg, D. L. Hartill, R. Poling, I. J. Kim, M. Goldberg, E. H. Thorndike, T. Copie, L. Garren, C. Bebek, F. M. Pipkin, P. Lubrano, W. Y. Chen, M. S. Alam, Sheldon Stone, S. E. Csorna, M. Procario, N. Horwitz, R. DeSalvo, Paul Avery, Thomas Ferguson, D. L. Kreinick, M. Sapper, J. Byrd, K. Kinoshita, N. Katayama, G. C. Moneti, Ian Shipsey, Persis S. Drell, E. I. Shibata, F. Morrow, R. S. Galik, D. H. Miller, Y. Kubota, Richard Wilson, A. J. Sadoff, J. Wolinski, Ian Brock, M. D. Mestayer, A. Silverman, J. Whitmore, M. Pisharody, W. C. Li, Karl Berkelman, Themistocles Bowcock, C. H. Park, Ha Lam, T. Jensen, A. M. Halling, N. B. Mistry, R. L. McIlwain, J. D. Lewis, M. Worris, D. Besson, D. R. Johnson, J. Kandaswamy, K. Sparks, C. R. Sun, R. D. Kass, C. R. Ng, A. Jawahery, D. Peterson, Xinchou Lou, Marina Artuso, Daniela Bortoletto, J. W. Dewire, Elliott Cheu, Glen D. Crawford, D. Riley, E. Blucher, John Yelton, R. Namjoshi, M. Hempstead, James Alexander, V. Sharma, T. Letson, R. Ehrlich, S. Nandi, D. M. Coffman, B. K. Heltsley, H. Worden, C. O'Grady, Tomasz Skwarnicki, D. Perticone, P. Haas, James Mueller, Philip Baringer, D. Xiao, and S. W. Gray

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, Intellectual and Developmental Disabilities (IDD), High Energy Physics::Phenomenology, Nuclear Theory, Molecular, Branching (polymer chemistry), Nuclear & Particles Physics, Atomic, Brain Disorders, Nuclear physics, Particle and Plasma Physics, Nuclear, High Energy Physics::Experiment, Down Syndrome, Intellectual and Developmental Disabilities, Nuclear Experiment, Astronomical and Space Sciences, Mathematical Physics
Abstract

Using the CLEO detector, we have measured the branching ratios for the exclusive decays of the D s + meson into K ∗0 K + , K 0 K + , and K ∗+ K 0 relative to the decay D s + →φπ + to be close to unity. We have also measured the mass diference between the D s + and D + meson to be 98.5±1.5 MeV/ c 2 .

Published
1989

43. Charm production in nonresonante+e−annihilations at√s =10.55 GeV

Author

D. G. Cassel, Thomas Ferguson, W. C. Li, Daniela Bortoletto, T. Jensen, Ian Brock, J. W. Dewire, V. Tanikella, R. Kowalewski, Murdock Gilchriese, B. Gittelman, R. DeSalvo, R. S. Galik, Y. Kubota, G. C. Moneti, I. J. Kim, M. Procario, Ian Shipsey, D. Perticone, S. Holzner, S. Behrends, E. H. Thorndike, D. Riley, D. R. Johnson, N. B. Mistry, F. M. Pipkin, L. Garren, A. M. Halling, D. Besson, S. E. Csorna, M. S. Alam, F. Morrow, E. Blucher, E. I. Shibata, G. B. Word, Xinchou Lou, K. Kinoshita, A. Silverman, Ron Poling, M. Hempstead, C. Bebek, Joan A. Guida, J. Kandaswamy, R. W. Kraemer, R. S. Panvini, G. J. Bobbink, A. Jawahery, J. Wolinski, R. Namjoshi, Paul Tipton, S. W. Gray, Jan M. Guida, D. Peterson, D. Xiao, H. Kagan, Sheldon Stone, Paul Avery, T. Letson, D. H. Miller, T. Copie, M. Goldberg, Richard Wilson, M. D. Mestayer, C. R. Sun, A. J. Sadoff, R. L. McIlwain, R. D. Kass, T. J. V. Bowcock, D. L. Hartill, P. Haas, P. Lubrano, Hans J. Vogel, R. Holmes, N. Katayama, P. Thoma, N. Horwitz, Alice Bean, M. Pisharody, Karl Berkelman, D. L. Kreinick, B. K. Heltsley, Kenneth Francis Read, E. Nordberg, V. Sharma, R. Ehrlich, P. Baringer, and James Mueller

Subjects
Nuclear physics, Quantum chromodynamics, Charmed baryons, Baryon, Physics, Particle physics, Annihilation, Meson, Electron–positron annihilation, Hadron, Charm (quantum number), GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries)
Abstract

This is the publisher's version also available electronically from http://journals.aps.org/prd/abstract/10.1103/PhysRevD.37.1719

Published
1988

44. Improved upper limit on flavor-changing neutral-current decays of thebquark

Author

A. M. Halling, I. J. Kim, S. W. Gray, Murdock Gilchriese, Chih-Ree Sun, D. Perticone, P. Lubrano, B. Gittelman, S. Holzner, S. Behrends, Xinchou Lou, D. Riley, T. Copie, C. Bebek, R. Holmes, A. Engler, W. C. Li, Paul Tipton, T. Jensen, Thomas Ferguson, M. Hempstead, N. Horwitz, Themistocles Bowcock, L. Garren, R. S. Galik, Y. Kubota, Ron Poling, Ian Shipsey, A. Chen, Harris Kagan, Alice Bean, E. H. Thorndike, Joan A. Guida, E. Nordberg, F. M. Pipkin, J. Kandaswamy, P. Thoma, R. W. Kraemer, Jan M. Guida, G. B. Word, S. E. Csorna, F. Morrow, V. Tanikella, A. Silverman, D. Peterson, M. Pisharody, Karl Berkelman, R. S. Panvini, G. J. Bobbink, K. Kinoshita, C. Rippich, D. Xiao, D. G. Cassel, Ian Brock, R. Kowalewski, Hans J. Vogel, R. D. Kass, A. J. Sadoff, R. DeSalvo, J. Wolinski, Richard Wilson, G. C. Moneti, N. Katayama, N. B. Mistry, P. Haas, Sheldon Stone, Paul Avery, A. Jawahery, E. Blucher, M. Goldberg, R. Namjoshi, M. S. Alam, M. D. Mestayer, Daniela Bortoletto, James Mueller, J. W. Dewire, V. Sharma, R. Ehrlich, D. Besson, M. Procario, D. L. Hartill, B. K. Heltsley, Kenneth Francis Read, and D. L. Kreinick

Subjects
Physics, Particle decay, Particle physics, Meson, Branching fraction, Electron–positron annihilation, Flavor-changing neutral current, High Energy Physics::Phenomenology, Hadron, High Energy Physics::Experiment, B meson, Bottom quark
Abstract

We report the results of a new search for flavor-changing neutral-current decays of the b quark and present a 90%-confidence-level upper limit for the branching fraction for B\ensuremath{\rightarrow}${l}^{+}$${l}^{\mathrm{\ensuremath{-}}}$X of 1.2\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}3}$.

Published
1987

45. Study of the decay B¯0→D+l−ν¯

Author

D. Bortoletto, M. Goldberg, N. Horwitz, M. D. Mestayer, G. C. Moneti, V. Sharma, I. P. J. Shipsey, T. Skwarnicki, S. E. Csorna, T. Letson, I. C. Brock, T. Ferguson, J. Alexander, M. Artuso, C. Bebek, K. Berkelman, D. G. Cassel, E. Cheu, D. M. Coffman, G. Crawford, J. W. DeWire, P. S. Drell, R. Ehrlich, R. S. Galik, B. Gittelman, S. W. Gray, A. M. Halling, D. L. Hartill, B. K. Heltsley, J. Kandaswamy, R. Kowalewski, D. L. Kreinick, Y. Kubota, J. D. Lewis, N. B. Mistry, J. Mueller, R. Namjoshi, S. Nandi, E. Nordberg, C. O’Grady, D. Peterson, M. Pisharody, D. Riley, M. Sapper, A. Silverman, S. Stone, H. Worden, M. Worris, A. J. Sadoff, P. Avery, D. Besson, L. Garren, J. Yelton, T. Bowcock, K. Kinoshita, F. M. Pipkin, M. Procario, Richard Wilson, J. Wolinski, D. Xiao, R. Ammar, P. Baringer, P. Haas, Ha Lam, A. Jawahery, C. H. Park, D. Perticone, R. Poling, R. Fulton, M. Hempstead, T. Jensen, D. R. Johnson, H. Kagan, R. Kass, F. Morrow, J. Whitmore, W.-Y. Chen, R. L. McIlwain, D. H. Miller, C. R. Ng, E. I. Shibata, W.-M. Yao, K. Sparks, E. H. Thorndike, M. S. Alam, N. Katayama, I. J. Kim, W. C. Li, X. C. Lou, and C. R. Sun

Subjects
Physics, Semileptonic decay, Crystallography, Particle decay, Antiparticle, Meson, Branching fraction, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Hadron, General Physics and Astronomy, B meson, Cornell Electron Storage Ring
Abstract

Using a sample of 484 000 {ital B} mesons collected with the CLEO detector at the Cornell Electron Storage Ring, we have measured {ital B}({ital {bar B}}{sup 0}{r arrow}D{sup *+}l{sup {minus}}{nu}) and found that the polarization of the {ital D}{sup *+} is small. These results are compared with models of semileptonic {ital B} decay.

Published
1989

46. Semileptonic decays ofBmesons

Author

E. H. Thorndike, N. B. Mistry, P. Avery, F. M. Pipkin, F. Morrow, M. Herzlinger, D. Herrup, G. Rucinski, J. S. Dewire, A. Snyder, A. J. Sadoff, M. S. Alam, N. Horwitz, W. Tanenbaum, Ron Poling, R. Perchonok, D. Weber, Joan A. Guida, J. Kandaswamy, P. Pistilli, A. C. Melissinos, D. Andrews, R. S. Panvini, K. Chadwick, Sheldon Stone, H. Kooy, A. Fridman, A. Silverman, T. Gentile, T. Ferguson, Robert Stone, M. Hempstead, R. Cabenda, D. L. Hartill, R. Plunkett, C. Rosenfeld, S. L. Olsen, A. Chen, James C. Green, C. J. Bebek, R. D. Kass, G. C. Moneti, J. Chauveau, F. Sannes, J. Haggerty, R. Ehrlich, W. W. MacKay, Joseph Izen, Richard Wilson, P. Ganci, D. G. Cassel, A. Brody, D. L. Kreinick, R. G. Hicks, J. Rohlf, P. C. Stein, S. E. Csorna, M. Goldberg, Harris Kagan, R. Wilcke, Murdock Gilchriese, B. Gittelman, J. Mueller, W. A. Loomis, E. Nordberg, and P. Skubic

Subjects
Semileptonic decay, Physics, Particle physics, Meson, Branching fraction, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Nuclear physics, Particle decay, High Energy Physics::Experiment, B meson, Nuclear Experiment, Lepton
Abstract

We have studied the production of B mesons in e/sup +/e/sup -/ annihilations and present new measurements of the semileptonic branching fractions for B-meson decay. We find B(B..-->..e..nu..X) = 0.127 +- 0.017 +- 0.013 and B(B..--> mu nu..X) = 0.122 +- 0.017 +- 0.031, where the errors are statistical and systematic, respectively. The observed lepton momentum spectra from B decays are presented. From these spectra we find the mean hadronic mass (M/sub X/) recoiling against the detected lepton to be M/sub X/ = 2.2 +- 0.2 GeV/c/sup 2/. We have also observed an enhancement in the lepton yield from the continuum above BB-bar threshold. This enhancement is interpreted as continuum B production and is consistent with what is expected from the naive quark model.

Published
1983

47. High-statistics study ofϒ(2S)→π+π−ϒ(1S)

Author

D. L. Hartill, Ron Poling, Y. Kubota, S. Holzner, S. Behrends, M. Goldberg, G. C. Moneti, Richard Wilson, R. Namjoshi, Paul Tipton, Joan A. Guida, J. Kandaswamy, D. G. Cassel, M. Hempstead, R. Wilcke, S. L. Olsen, Murdock Gilchriese, T. Gentile, B. Gittelman, L. Garren, W. W. MacKay, R. D. Kass, E. H. Thorndike, A. Chen, M. Ogg, H. Van Hecke, J. W. Dewire, F. M. Pipkin, F. Sannes, N. B. Mistry, R. Ehrlich, Jan M. Guida, C. Bebek, G. Parkhurst, M. D. Mestayer, M. S. Alam, D. Weber, R. S. Panvini, R. G. Hicks, Xia Yi, F. Morrow, Karl Berkelman, J. Hassard, A. Silverman, N. Horwitz, R. S. Galik, H. Kagan, M. Ito, J. Chauveau, M. Halling, R. T. Giles, A. C. Melissinos, A. J. Sadoff, C. G. Trahern, P. Avery, P. Haas, Robert Stone, D. Besson, P. C. Stein, S. E. Csorna, James C. Green, K. Kinoshita, C. Rosenfeld, P. Lipari, D. Peterson, T. Jensen, Sheldon Stone, K. Chadwick, E. Nordberg, T. Ferguson, P. Skubic, A. Jawahery, D. L. Kreinick, and A. Snyder

Subjects
Physics, Particle decay, Pion, Meson, Branching fraction, Electron–positron annihilation, Hadron, Analytical chemistry, Elementary particle, Cornell Electron Storage Ring
Abstract

A detailed investigation of the decay UPSILON(2S)..--> pi../sup +/..pi../sup -/UPSILON(1S) has been made from 128 000 UPSILON(2S) decays observed in the CLEO detector at the Cornell Electron Storage Ring (CESR). We find this branching ratio to be (19.1 +- 1.2 +- 0.6)%. The properties of the ..pi pi.. system have been studied using 491 exclusive events of the type UPSILON(2S)..--> pi../sup +/..pi../sup -/UPSILON(1S), UPSILON(1S)..-->..e/sup +/e/sup -/ or ..mu../sup +/..mu../sup -/. Assuming e-..mu.. universality we find B(UPSILON(1S)..--> mu../sup +/..mu../sup -/) = (2.84 +- 0.18 +- 0.20)%. A search for UPSILON(2S)..-->..etaUPSILON(1S) yields an upper limit of 1% at the 90% confidence level for this branching ratio. We have also searched for (UPSILON(2S) or UPSILON(3S))..--> pi../sup +/..pi../sup -/UPSILON(1S), UPSILON(1S)..-->..noninteracting particles.

Published
1984

48. Study of the decayB→ψX

Author

Jan M. Guida, C. Rippich, T. Copie, Chih-Ree Sun, Ron Poling, R. D. Kass, D. Perticone, S. Holzner, S. Behrends, I. J. Kim, J. Wolinski, C. Bebek, M. Pisharody, S. W. Gray, N. Katayama, Karl Berkelman, P. Lubrano, Joan A. Guida, Richard Wilson, E. H. Thorndike, J. Kandaswamy, Sheldon Stone, D. G. Cassel, M. D. Mestayer, B. K. Heltsley, A. Jawahery, Kenneth Francis Read, Paul Avery, F. M. Pipkin, R. Kraemer, R. Holmes, A. Engler, Alice Bean, D. Riley, A. Chen, T. J. V. Bowcock, J. Hassard, A. Silverman, R. S. Panvini, D. Peterson, Ian Brock, Thomas Ferguson, R. Kowalewski, M. Hempstead, H. Kagan, R. DeSalvo, T. Jensen, M. Goldberg, G. C. Moneti, E. Nordberg, R. S. Galik, N. Horwitz, D. L. Kreinick, Y. Kubota, M. Ogg, S. E. Csorna, N. B. Mistry, A. J. Sadoff, E. Blucher, R. Namjoshi, P. Haas, Murdock Gilchriese, B. Gittelman, D. Xiao, M. Ito, R.B. Sutton, F. Morrow, Hans J. Vogel, R. T. Giles, K. Kinoshita, C. Rosenfeld, M. S. Alam, G. B. Word, Paul Tipton, L. Garren, Daniela Bortoletto, J. W. Dewire, D. Besson, D. L. Hartill, T. Gentile, Xia Yi, G. J. Bobbink, James Mueller, V. Sharma, R. Ehrlich, V. Tanikella, and A. M. Halling

Subjects
Physics, Meson, Branching fraction, Electron–positron annihilation, Hadron, Quark model, Mass spectrum, Analytical chemistry, B meson, Elementary particle
Abstract

We have measured the inclusive branching ratio for B..-->..psiX to be (1.09 +- 0.16 +- 0.21)%, and the exclusive branching ratios for B/sup -/..-->..psiK/sup -/ and B-bar /sup 0/..-->..psiK-bar /sup *//sup 0/ to be (0.09 +- 0.05)% and (0.41 +- 0.18)%, respectively. The mass difference between neutral and charged B mesons is 1.1 +- 2.1 MeV, while the difference between the mass of UPSILON(4S) and twice the mean B-meson mass is 18.5 +- 3.0 MeV. The psi momentum distribution implies a substantial two-body decay (in agreement with direct measurements), but also some combination of B..-->..psiX with M/sub X/>1.5 GeV, and B..-->..psi'X.

Published
1986

49. Γ(b→ulν)/Γ(b→clν) from the end point of the lepton momentum spectrum in semileptonicBdecay

Author

A. J. Sadoff, D. L. Hartill, I. P.J. Shipsey, M. Hempstead, A. M. Halling, James Mueller, R. S. Panvini, B. K. Heltsley, Kenneth Francis Read, T. J. V. Bowcock, C. R. Sun, D. L. Kreinick, C. Bebek, P. Haas, G.J. Bobbink, A. Chen, Xinchou Lou, R. D. Kass, S. E. Csorna, J. Wolinski, E. H. Thorndike, F. M. Pipkin, M. D. Mestayer, Sheldon Stone, Paul Avery, K. Kinoshita, R. Ehrlich, N. Horwitz, V. Tanikella, T. Jensen, R. S. Galik, C. Rippich, M. S. Alam, E. Blucher, E. Nordberg, Jan M. Guida, Murdock Gilchriese, B. Gittelman, Wei Li, P. Thoma, P. Lubrano, I. J. Kim, R. Holmes, Daniela Bortoletto, A. Jawahery, M. Pisharody, J. W. Dewire, Karl Berkelman, Alice Bean, Hans J. Vogel, Paul Tipton, D. G. Cassel, Richard Wilson, D. Riley, N. Katayama, Thomas Ferguson, R. Poling, I. C. Brock, Yuichi Kubota, Joan A. Guida, J. Kandaswamy, D. Peterson, L. Garren, R. Kowalewski, F. Morrow, D. Xiao, M. Goldberg, G. C. Moneti, Vivek Sharma, T. Copie, A. Engler, A. Silverman, G. B. Word, D. Z. Besson, N. B. Mistry, M. Procario, D. Perticone, R. Desalvo, S. Holzner, S. Behrends, R. W. Kraemer, R. Namjoshi, S. W. Gray, and H. Kagan

Subjects
Physics, Momentum (technical analysis), Particle physics, End point, Electron–positron annihilation, Spectrum (functional analysis), General Physics and Astronomy, Lepton
Published
1987

50. ΛcProduction frome+e−Annihilation in theϒEnergy Region

Author

Murdock Gilchriese, B. Gittelman, Jan M. Guida, M. Ito, D. Bartoletto, D. Peterson, Paul Tipton, Ron Poling, D. G. Cassel, R. S. Galik, Xia Yi, R. DeSalvo, Themistocles Bowcock, G. C. Moneti, R. D. Kass, C. Bebek, G. Parkhurst, Y. Kubota, D. Besson, R. S. Panvini, D. L. Hartill, A. Chen, P. Lubrano, F. Sannes, Richard Wilson, D. Perticone, S. Holzner, S. Behrends, James C. Green, E. H. Thorndike, A. M. Halling, T. Copie, J. W. Dewire, F. M. Pipkin, M. Goldberg, M. S. Alam, Thomas Ferguson, Robert Stone, C. Rosenfeld, G. B. Word, P. C. Stein, S. E. Csorna, H. Kagan, Alice Bean, Sheldon Stone, K. Kinoshita, M. D. Mestayer, C. G. Trahern, P. Avery, N. B. Mistry, R. Namjoshi, S. W. Gray, Joan A. Guida, J. Kandaswamy, F. Morrow, A. J. Sadoff, M. Hempstead, T. Gentile, P. Haas, M. Ogg, J. Hassard, A. Silverman, E. Nordberg, R. T. Giles, P. Skubic, N. Horwitz, A. Jawahery, H. Van Hecke, M. Pisharody, Karl Berkelman, Xu Kezun, B. K. Heltsley, Kenneth Francis Read, D. L. Kreinick, T. Jensen, L. Garren, and R. Ehrlich

Subjects
Physics, Particle physics, Annihilation, Meson, Branching fraction, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, General Physics and Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Lambda, Nuclear physics, Baryon, Particle decay, Pion, High Energy Physics::Experiment, Nuclear Experiment
Abstract

We have observed ..lambda../sub c/ baryons in nonresonant e/sup +/e/sup -/ annihilation at energies around ..sqrt..s = 10.5 GeV through their decay to ..lambda pi../sup +/..pi../sup +/..pi../sup -/. We measure the branching fraction to be (2.8 +- 0.7 +- 1.1)%. The momentum spectrum of the ..lambda../sub c/ is similar to that of charmed mesons, providing a constraint on models of charmed-quark hadronization.

Published
1985

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