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1. Status of the BNL muon (g-2) experiment.

Author

Ralf Prigl, H. N. Brown, G. Bunce, R. M. Carey, Priscilla B. Cushman, G. T. Danby, P. T. Debevec, H. Deng, W. Deninger, S. K. Dhawan, V. P. Druzhinin, L. Duong, W. Earle, E. Efstathiadis, F. J. M. Farley, G. V. Fedotovich, S. Giron, Frederick Gray, M. Grosse Perdekamp, A. Grossmann, U. Haeberlen, M. Hare, E. S. Hazen, D. W. Hertzog, V. W. Hughes, Masahiko Iwasaki, K. Jungmann, D. Kawall, M. Kawamura, B. I. Khazin, J. Kindem, F. Krienen, I. Kronkvist, R. Larsen, Y. Y. Lee, W. Liu, I. Logashenko, R. McNabb, W. Meng, J.-L. Mi, D. Miller, J. P. Miller, W. M. Morse, P. Neumayer, C. J. G. Onderwater, Y. Orlov, C. Pai, C. Polly, J. Pretz, G. zu Putlitz, S. I. Redin, O. Rind, B. L. Roberts, N. Ryskulov, R. Sanders, S. Sedykh, Y. K. Semertzidis, S. Serednyakov, Yu. M. Shatunov, Evgeny Solodov, M. Sossong, A. Steinmetz, L. R. Sulak, M. Tanaka, C. Timmermans, A. Trofimov, D. Urner, D. Warburton, D. Winn, A. Yamamoto, and D. Zimmerman

Published
1999
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2. PRODUCTION OF NEUTRAL STRANGE PARTICLES IN MUON-NUCLEON SCATTERING AT 490 GEV

Author

H. J. Gebauer, J. F. Bartlett, M. Wilhelm, I. Derado, S. Krzywdzinski, H. E. Stier, Jan Figiel, S. Wolbers, W. Mohr, P. L. Anthony, S. Aïd, M. Erdmann, Jim Hanlon, S. Magill, M. D. Baker, Henry Lubatti, H. M. Braun, H. J. Seyerlein, S. K. Dhawan, Shuichi Kunori, G. A. Snow, M. Aderholz, D. E. Jaffe, D. Hantke, L.S. Osborne, K. Dziunikowska, S. O'Day, A. Manz, Michael Schmitt, G. Jancso, A. Röser, K. Kadija, F. M. Pipkin, A. Salvarani, U. Ecker, Mark Raymond Adams, S. Tentindo-Repond, D. McLeod, H. E. Jackson, D. G. Michael, R. L. Talaga, P. Malecki, Andris Skuja, J. J. Ryan, J. Wilkes, P. Stopa, Ronald Gilman, R. D. Kennedy, V. Eckardt, H. E. Montgomery, Norbert Schmitz, V. W. Hughes, C. W. Salgado, V. Papavassiliou, M. C. Green, D. F. Geesaman, T. Dreyer, H. J. Trost, Janet Conrad, Jorge G. Morfin, Wit Busza, H. Venkataramania, J. Haas, G. Coutrakon, C. Halliwell, S. Söldner-Rembold, Tiefu Zhao, S. B. Kaufman, A. A. Bhatti, K. Olkiewicz, R. B. Nickerson, A. Eskreys, R. A. Swanson, P. H. Steinberg, H. Schellman, J. J. Lord, W. Dougherty, D. M. Jansen, K. P. Schüler, E. J. Ramberg, T. Kirk, H. L. Melanson, B. Pawlik, Richard Wilson, R. Davisson, W. Wittek, and H. G. E. Kobrak

Subjects
Quantum chromodynamics, Physics, Particle physics, Muon, Physics and Astronomy (miscellaneous), Scattering, Multiplicity (mathematics), Elementary particle, Strangeness, Lambda, Nuclear physics, High Energy Physics::Experiment, Nuclear Experiment, Nucleon, Engineering (miscellaneous)
Abstract

The production of K0, Λ and {Mathematical expression} particles is studied in the E665 muon-nucleon experiment at Fermilab. The average multiplicities and squared transverse momenta are measured as a function of xF and W2. Most features of the data can be well described by the Lund model. Within this model, the data on the K0/π± ratios and on the average K0 multiplicity in the forward region favor a strangeness suppression factor s/u in the fragmentation process near 0.20. Clear evidence for QCD effects is seen in the average squared transverse momentum of K0 and Λ particles. © 1994 Springer-Verlag.

Published
2016

3. DENSITY AND CORRELATION INTEGRALS IN DEEP-INELASTIC MUON-NUCLEON SCATTERING AT 490 GEV

Author

M. Wilhelm, G. A. Snow, D. E. Jaffe, R. Davisson, S. Aïd, F. M. Pipkin, H. E. Stier, Richard Wilson, W. Dougherty, H. Venkataramania, Norbert Schmitz, W. Wittek, Henry Lubatti, A. Manz, R. L. Talaga, S. O'Day, K. Kadija, Wit Busza, H. G. E. Kobrak, Shuichi Kunori, K. Dziunikowska, L.S. Osborne, K. Olkiewicz, D. G. Michael, Andris Skuja, M. R. Adams, Pa. Malecki, J. Wilkes, H. J. Gebauer, R. B. Nickerson, R. D. Kennedy, J. F. Bartlett, B. Pawlik, I. Derado, V. Eckardt, D. F. Geesaman, A. Salvarani, H. E. Montgomery, E. J. Ramberg, Martin Erdmann, U. Ecker, Jorge G. Morfin, M. C. Green, W. Mohr, Janet Conrad, J. J. Lord, V. Papavassiliou, H. J. Trost, S. Krzywdzinski, A. A. Bhatti, D. McLeod, G. Jancso, Michael Schmitt, Satish Dhawan, C. Halliwell, S. Tentindo-Repond, H. L. Melanson, Jan Figiel, D. M. Jansen, A. Röser, Ronald Gilman, H. E. Jackson, Jim Hanlon, V. W. Hughes, H. M. Braun, S. Wolbers, S. Magill, C. W. Salgado, P. Stopa, J. J. Ryan, M. D. Baker, K. P. Schüler, D. Hantke, F. Botterweck, A. Eskreys, R. A. Swanson, P. H. Steinberg, H. Schellman, T. Kirk, H. J. Seyerlein, T. Dreyer, J. Haas, P.L. Anthony, G. Coutrakon, S. Söldner-Rembold, Tiefu Zhao, and S. B. Kaufman

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Scattering, Hadron, Tevatron, Deep inelastic scattering, law.invention, Nuclear physics, law, Intermittency, High Energy Physics::Experiment, Fermilab, Nucleon
Abstract

Results on density integrals Fq(Q2) and correlation integrals Kq(Q2) are presented for the first time in muon-nucleon scattering at ∼ 490 GeV, using data from the E665 experiment at the Tevatron of Fermilab. A clear rise of the Fq integrals with decreasing size of the phase-space cells (“intermittency”) is observed for pairs and triplets of negative hadrons whereas the effect is much weaker for mixed charge combinations. From these findings it is concluded that the observed intermittency signal is mainly caused by Bose-Einstein interference. Furthermore, no energy (W) dependence of F2(Q2) is observed within the W range of the E665 experiment. Finally, the third-order correlation integrals K3(Q2) are found to be significantly different from zero which implies the presence of genuine three-particle correlations in muon-nucleon interactions.

Published
2016

4. A spectrometer for muon scattering at the Tevatron

Author

A. Eskreys, J. Wilkes, P. H. Steinberg, A. Salvarani, S. Söldner-Rembold, M. Vidal, S. A. Wolbers, L. S. Osborne, S. K. Dhawan, A. A. Bhatti, A. Röser, K. P. Schüler, D. G. Michael, D. M. Jansen, D. McLeod, Andris Skuja, C. Halliwell, P. Stopa, U. Ecker, H. E. Stier, B. Pawlik, S. B. Kaufman, M. Erdmann, G. Jancso, R. D. Kennedy, T. Kirk, H. Venkataramania, T. Lyons, H. M. Braun, P. Strube, E. Sexton, J. Hanlon, H. J. Gebauer, V. Eckardt, Michael Schmitt, S. Tentindo-Repond, Shuichi Kunori, H. E. Montgomery, T. Dreyer, Robert A. Swanson, Ronald Gilman, R. Davisson, P. L. Anthony, H. L. Melanson, F. M. Pipkin, Jorge G. Morfin, J. Haas, John P. Ryan, Richard Wilson, T. Burnett, M. D. Baker, H. J. Seyerlein, M. C. Green, S. O'Day, M. Wilhelm, A. M. Osborne, H. J. Trost, Janet Conrad, W. Dougherty, P. Malecki, H. Kobrak, E. J. Ramberg, G. Coutrakon, Tianchi Zhao, Wit Busza, V. W. Hughes, R. B. Nickerson, D. F. Geesaman, Mark Raymond Adams, R. L. Talaga, S. Magill, S. Aïd, A. Manz, Henry Lubatti, K. Eskreys, H. E. Jackson, J. F. Bartlett, W. Mohr, S. Krzywdzinski, and J. Lord

Subjects
Physics, Nuclear and High Energy Physics, Wire chamber, Particle physics, Muon, Spectrometer, Physics::Instrumentation and Detectors, Scattering, Tevatron, Particle detector, Particle identification, Nuclear physics, Physics::Accelerator Physics, High Energy Physics::Experiment, Instrumentation, Fermi Gamma-ray Space Telescope
Abstract

In this paper the spectrometer constructed by the E665 Collaboration is described. The spectrometer was built during the period 1982–87 and the first data were taken during the 1987–88 Fixed Target run of the Fermi National Accelerator Laboratory (FNAL) Tevatron. This is the first of a series of runs in which a comprehensive program of high energy muon scattering experiments will be performed.

Published
2016

5. NUCLEAR SHADOWING, DIFFRACTIVE SCATTERING AND LOW MOMENTUM PROTONS IN MU-XE INTERACTIONS AT 490-GEV

Author

H. E. Stier, F. M. Pipkin, G. Coutrakon, Jim Hanlon, H. M. Braun, K. Kadija, K. Olkiewicz, A. Salvarani, Henry Lubatti, D. G. Michael, G. Jancso, P. Malecki, M. Wilhelm, S. Krzywdzinski, W. Wittek, A. Eskreys, M. Erdmann, H. G. E. Kobrak, Andris Skuja, R. A. Swanson, P. L. Anthony, P. H. Steinberg, T. Dreyer, Jan Figiel, S. Aïd, S. Wolbers, V. W. Hughes, J. F. Bartlett, C. Halliwell, M. C. Green, H. J. Trost, I. Derado, L.S. Osborne, P. Stopa, U. Ecker, M. D. Baker, C. W. Salgado, R. D. Kennedy, W. Mohr, J. Haas, B. Pawlik, D. Hantke, R. B. Nickerson, Shuichi Kunori, S. Söldner-Rembold, D. E. Jaffe, Mark Raymond Adams, Ronald Gilman, H. J. Seyerlein, Tiefu Zhao, V. Eckardt, R. L. Talaga, S. O'Day, D. F. Geesaman, H. E. Montgomery, S. Magill, T. Kirk, H. Schellman, S. B. Kaufman, H. E. Jackson, Janet Conrad, V. Papavassiliou, R. Davisson, Timothy J. Carroll, H. L. Melanson, E. J. Ramberg, Jorge G. Morfin, D. M. Jansen, S. K. Dhawan, M. Aderholz, A. Röser, J. Wilkes, A. A. Bhatti, H. Venkataramania, J. J. Ryan, K. P. Schüler, Richard Wilson, A. Manz, K. Dziunikowska, D. McLeod, G. A. Snow, Michael Schmitt, S. Tentindo-Repond, J. J. Lord, W. Dougherty, H. J. Gebauer, Norbert Schmitz, and Wit Busza

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Spectrometer, Scattering, Hadron, Tevatron, Elementary particle, Nuclear physics, Particle acceleration, Rapidity, High Energy Physics::Experiment, Fermilab, Nuclear Experiment, Engineering (miscellaneous)
Abstract

The production of charged hadrons is studied in μXe and μD interactions at 490 GeV beam energy. The data were taken at the Tevatron at Fermilab with the E665 spectrometer, equipped with a streamer chamber as vertex detector. Differences between the μXe and μD data are explained by cascading of hadrons in the Xe nucleus. The average multiplicity of charged hadrons in μXe scattering is compared to previously published pXe scattering data and is found to be strongly reduced. This is traced back to the low number of ‘projectile’ collisions in μXe interactions. From a study of thex Bj dependence of hadron production in μXe scattering, and by considering events with a large rapidity gap, evidence is found for a significant contribution of diffractive scattering, which is enhanced in the kinematic region where shadowing of the cross section is observed. This result supports recent models in which diffractive scattering and nuclear shadowing are closely related.

Published
2016

6. Statistical equations and methods applied to the precision muon experiment at BNL

Author

H. N. Brown, S. Sedykh, Lawrence Sulak, F. J. M. Farley, J. M. Paley, G. zu Putlitz, S. I. Redin, Klaus-Peter Jungmann, F. Krienen, L. Duong, I. Kronkvist, Masahiko Iwasaki, T. Qian, P. T. Debevec, Alexei Trofimov, Wuzheng Meng, J. P. Miller, D. Kawall, M. Grosse-Perdekamp, R. Prigl, J. Mi, R. McNabb, E. Efstathiadis, A. Steinmetz, A. Yamamoto, Yannis K. Semertzidis, D. Nikas, G. Bunce, B. L. Roberts, B. Bousquet, J. Kindem, C. Ozben, G. W. Bennett, B.I. Khazin, Q. Peng, C. Timmermans, A. Lam, I. Logashenko, M. Kawamura, Frederick Gray, M. Deile, William Morse, Yu. F. Orlov, M. Sossong, V. W. Hughes, Yu. M. Shatunov, O. Rind, G.V. Fedotovich, D.N. Grigoriev, N.M. Ryskulov, P. M. Shagin, A. Grossmann, Y.Y. Lee, D. Warburton, J. Pretz, G. T. Danby, P. von Walter, Satish Dhawan, E. P. Sichtermann, V. P. Druzhinin, Rasmus Larsen, H. Deng, M. F. Hare, D. Winn, D. Urner, X. Huang, C. J. G. Onderwater, E. P. Solodov, R. M. Carey, D. Zimmerman, C. C. Polly, William Deninger, D. W. Hertzog, S. Giron, and P. Cushman

Subjects
Physics, Larmor precession, Nuclear and High Energy Physics, Muon, Quality (physics), Nuclear magnetic resonance, Minification, Electron, Function (mathematics), Instrumentation, Spin-½, Computational physics, Weighting
Abstract

In the muon ( g - 2 ) experiment at Brookhaven National Laboratory, the spin precession frequency ω a is obtained from a standard χ 2 minimization fit applied to the time distribution of decay electrons. The unusually high accuracy ( ∼ 0.5 ppm ) of the experiment puts stringent requirements on the quality of the fit and the level of understanding of the statistical properties of the fitted parameters. We discuss the properties of the fits and their implications on the derived value for ω a , including estimates of the effect of an imperfect fit function, methods of including additional external information to reduce the error, the effects of splitting the data into many smaller subsets of data, applying different weighting methods to the data using energy information, and various tests of data suitability.

Published
2007

7. Measurement of the pion form factor in the range 1.04–1.38 GeV with the CMD-2 detector

Author

V. M. Aul’chenko, R. R. Akhmetshin, V. Sh. Banzarov, L. M. Barkov, N. S. Bashtovoi, D. V. Bondarev, A. E. Bondar’, A. V. Bragin, A. A. Valishev, N. I. Gabyshev, D. A. Gorbachev, A. A. Grebenyuk, D. N. Grigor’ev, S. K. Dhawan, D. A. Epifanov, A. S. Zaitsev, S. G. Zverev, F. V. Ignatov, V. F. Kazanin, S. V. Karpov, I. A. Koop, P. P. Krokovny, A. S. Kuz’min, I. B. Logashenko, P. A. Lukin, A. P. Lysenko, A. I. Mil’shtein, K. Yu. Mikhailov, I. N. Nesterenko, M. A. Nikulin, A. V. Otboev, V. S. Okhapkin, E. A. Perevedentsev, A. A. Polunin, A. S. Popov, S. I. Redin, B. L. Roberts, N. I. Root, A. A. Ruban, N. M. Ryskulov, A. L. Sibidanov, V. A. Sidorov, A. N. Skrinsky, V. P. Smakhtin, I. G. Snopkov, E. P. Solodov, J. A. Thompson, G. V. Fedotovich, B. I. Khazin, V. W. Hughes, A. G. Shamov, Yu. M. Shatunov, B. A. Shwartz, S. I. Éidel’man, and Yu. V. Yudin

Subjects
Physics, Particle physics, Range (particle radiation), Pion, Physics and Astronomy (miscellaneous), Detector, Form factor (quantum field theory), Energy (signal processing), High Energy Physics - Experiment
Abstract

The cross section for the process $e^+e^-\to\pi^+\pi^-$ is measured in the c.m. energy range 1.04-1.38 GeV from 995 000 selected collinear events including 860000 $e^+e^-$ events, 82000 $\mu^+\mu^-$ events, and 33000 $\pi^+\pi^-$ events. The systematic and statistical errors of measuring the pion form factor are equal to 1.2-4.2 and 5-13%, respectively., Comment: 5 pages, 2 figures

Published
2005

8. The muonic hydrogen Lamb-shift experiment

Author

Livia Ludhova, V. W. Hughes, Randolf Pohl, C.M.B. Monteiro, Françoise Mulhauser, J.F.C.A. Veloso, Satish Dhawan, Yi-Wei Liu, F. J. Hartmann, L.M.P. Fernandes, Lucile Julien, J.M.F. dos Santos, João Cardoso, Franz Kottmann, Theodor W. Hänsch, Aldo Antognini, Paul E. Knowles, David Taqqu, L. A. Schaller, Catherine Schwob, François Nez, F. D. Amaro, François Biraben, Paul Indelicato, O. Huot, A. Dax, C.A.N. Conde, and Paul Rabinowitz

Subjects
Physics, Nuclear physics, Muon, Proton, Charge radius, Excited state, General Physics and Astronomy, Radius, Atomic physics, Spectroscopy, Lamb shift, Exotic atom
Abstract

The charge radius of the proton, the simplest nucleus, is known from electron-scattering experiments only with a surprisingly low precision of about 2%. The poor knowledge of the proton charge radius restricts tests of bound-state quantum electrodynamics (QED) to the precision level of about 6 × 10–6, although the experimental data themselves (1S Lamb shift in hydrogen) have reached a precision of 2 × 10–6. The determination of the proton charge radius with an accuracy of 10–3 is the main goal of our experiment, opening a way to check bound-state QED predictions to a level of 10–7. The principle is to measure the 2S–2P energy difference in muonic hydrogen (µ–p) by infrared laser spectroscopy. The first data were taken in the second half of 2003. Muons from our unique very-low-energy muon beam are stopped at a rate of ~100 s–1 in 0.6 mbar H2 gas where the lifetime of the formed µp(2S) atoms is about 1.3 µs. An incoming muon triggers a pulsed multistage laser system that delivers ~0.2 mJ at λ ≈ 6 µm. Following the laser excitation µp(2S) → µp(2P) we observe the 1.9 keV X-rays from 2P–1S transitions using large area avalanche photodiodes. The resonance frequency, and, hence, the Lamb shift and the proton radius, is determined by measuring the intensity of these X-rays as a function of the laser wavelength. A broad range of laser frequencies was scanned in 2003 and the analysis is currently under way. PACS Nos.: 36.10.Dr, 14.20.Dh, 42.62.Fi

Published
2005

9. Precise measurements of the hadronic cross sections at the VEPP-2M collider with the CMD-2 detector

Author

B.I. Khazin, V.Sh. Banzarov, Yu.V. Yudin, Alexander Valishev, P. Krokovny, N.M. Ryskulov, N.I. Root, G.V. Fedotovich, A.L. Sibidanov, A.A. Grebeniuk, V.A. Sidorov, A. Bondar, V. W. Hughes, L.M. Barkov, A.A. Ruban, A. P. Lysenko, S.I. Redin, V.M. Titov, D.V. Bondarev, A.S. Kuzmin, S. Eidelman, I.G. Snopkov, D.A. Gorbachev, K.Yu. Mikhailov, A.N. Skrinsky, J. P. Miller, V.S. Okhapkin, Yu. M. Shatunov, B. L. Roberts, E. P. Solodov, Ivan Koop, D.N. Grigoriev, I.B. Logashenko, Vassili Kazanin, S.E. Baru, N.S. Bashtovoy, J. A. Thompson, S.G. Zverev, R.R. Akhmetshin, A.V. Bragin, Fedor Ignatov, A.A. Polunin, V. M. Aulchenko, S.V. Karpov, A.S. Popov, P.A. Lukin, N. Gabyshev, and B. Shwartz

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Particle physics, Annihilation, Luminosity (scattering theory), Meson, Hadron, Detector, Atomic and Molecular Physics, and Optics, law.invention, Nuclear physics, law, High Energy Physics::Experiment, Nuclear Experiment, Collider, Astrophysics::Galaxy Astrophysics
Abstract

The current status of the updated results from the CMD-2 detector is presented. The cross sections of e + e − annihilation into hadrons were measured in the c.m. energy range from 0.37 to 1.39 GeV and are based on the total integrated luminosity of about 30 pb −1 . Results of refitting experimental data for the ρ, ω and mesons are reviewed.

Published
2004

10. Update: A reanalysis of hadronic cross section measurements at CMD-2

Author

Semen Eidelman, M. A. Nikulin, L.M. Barkov, A. I. Milstein, D. Epifanov, E.V. Anashkin, P.Yu. Stepanov, A.E. Bondar, B. L. Roberts, V.A. Sidorov, E. A. Kuraev, L.M. Kurdadze, Yu. M. Shatunov, Pavel Krokovny, E. P. Solodov, Andrej Arbuzov, J. A. Thompson, V. W. Hughes, J. P. Miller, D.V. Bondarev, G.V. Fedotovich, Andrey Vladimirovich Bogdan, N.M. Ryskulov, A.S. Zaitsev, Vladimir Smakhtin, R.R. Akhmetshin, B. Shwartz, A.S. Kuzmin, D.A. Gorbachev, A.L. Sibidanov, A.S. Popov, A. Baratt, P.A. Lukin, K.Yu. Mikhailov, Yu.E Lischenko, Vassili Kazanin, N. Gabyshev, V.Sh. Banzarov, A. A. Grebenuk, A.N. Skrinsky, I. Logashenko, B.I. Khazin, N.I. Root, F.V. Ignatov, and D.N. Grigoriev

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Cross section (physics), Particle physics, Luminosity (scattering theory), Pion, 010308 nuclear & particles physics, Electron–positron annihilation, 0103 physical sciences, Hadron, 010306 general physics, 01 natural sciences
Abstract

The updated results of the precise measurements of the processes e + e − → ρ → π + π − , e + e − → ω → π + π − π 0 and e + e − → φ → K 0 L K 0 S performed by the CMD-2 Collaboration are presented. The update appeared necessary due to an overestimate of the integrated luminosity in previous analyses.

Published
2004

11. Study of the process e+e−→ωπ0→π0π0γ in c.m. energy range 920–1380 MeV at CMD-2

Author

E. P. Solodov, Igor Nesterenko, Yu.V. Yudin, Vassili Kazanin, D. Epifanov, N.I. Root, R.R. Akhmetshin, Alexander Valishev, A.A. Polunin, B. L. Roberts, A.V. Otboev, P.Yu. Stepanov, A.V. Bragin, V.S. Okhapkin, E.A. Perevedentsev, I.B. Logashenko, Fedor Ignatov, G.V. Fedotovitch, I.G. Snopkov, L.M. Barkov, N.S. Bashtovoy, S.E. Baru, A.S. Kuzmin, K.Yu. Mikhailov, A. P. Lysenko, N.M. Ryskulov, S.I. Eidelman, Yu. M. Shatunov, D.N. Grigoriev, A.A. Grebeniuk, A.G. Shamov, B.A. Shwartz, S.G. Zverev, J. A. Thompson, A.S. Zaitsev, P. Krokovny, A. Baratt, V.M. Aulchenko, V.Sh. Banzarov, V.A. Sidorov, A. I. Milstein, Alexey Pak, D.V. Bondarev, A.S. Popov, P.A. Lukin, A.N. Skrinsky, V. W. Hughes, N. Gabyshev, S.V. Karpov, A.L. Sibidanov, I. A. Koop, A.A. Ruban, S.I. Redin, D.A. Gorbachev, A.E. Bondar, and B.I. Khazin

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Antiparticle, Annihilation, Pion, Meson, Electron–positron annihilation, Hadron, Atomic physics, Omega baryon, Lepton
Abstract

The cross section of the process e + e − → ωπ 0 → π 0 π 0 γ has been measured in the c.m. energy range 920–1380 MeV with the CMD-2 detector. Its energy dependence is well described by the interference of the ρ (770) and ρ (1450) mesons decaying to ωπ 0 . Upper limits for the cross sections of the direct processes e + e − → π 0 π 0 γ , ηπ 0 γ have been set.

Published
2003

12. Recent results from the BNL g-2 experiment

Author

D.N. Grigoriev, D. Zimmerman, M. Sossong, C. Ozben, C. C. Polly, P. Cushman, Satish Dhawan, J. Pretz, F. J. M. Farley, I. Logashenko, P. von Walter, E. P. Solodov, G. zu Putlitz, S. I. Redin, R. M. Carey, Klaus-Peter Jungmann, D. W. Hertzog, A. Grossman, Frederick Gray, F. Krienen, D. Urner, Masahiko Iwasaki, S. Giron, C. J. G. Onderwater, L. Duong, Wuzheng Meng, Y.Y. Lee, H. N. Brown, Rasmus Larsen, R. Prigl, J. Mi, L. R. Sulak, J. P. Miller, O. Rind, H. Deng, B. L. Roberts, R. McNabb, A. Yamamoto, J. M. Paley, N.M. Ryskulov, William Deninger, D. Winn, C. Timmermans, D. Warburton, Alexei Trofimov, Yannis K. Semertzidis, E. P. Sichtermann, E. Efstathiadis, A. Steinmetz, M. F. Hare, S. Sedykh, G.V. Fedotovich, William Morse, I. Kronkvist, M. Deile, G. T. Danby, D. Kawall, V. P. Druzhinin, D. Nikas, P. T. Debevec, V. W. Hughes, M. Grosse-Perdekamp, Yu. M. Shatunov, J. Kindem, B.I. Khazin, M. Kawamura, G. Bunce, and Yuri F. Orlov

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Anomalous magnetic dipole moment, Electron, Atomic and Molecular Physics, and Optics, Nuclear physics, Data set, Magnetic-moment, Physics::Accelerator Physics, High Energy Physics::Experiment, National laboratory, Storage ring
Abstract

The status of the muon g — 2 experiment at the AGS facility of Brookhaven National Laboratory is discussed. Data obtained in 1999 with positive muons has been analyzed and published. The final data set contained 0.95 × 10 9 events and had an accuracy of 1.3 ppm . Approximately four times more data with positive muons and three times more data with negative muons were obtained in 2000 and 2001, respectively. These data were obtained with a more uniform magnetic field and with different storage ring tunes. An accuracy of the order of 0.5 ppm is anticipated.

Published
2002

13. Recent results and current status of the muon g-2 experiment at BNL

Author

Alexei Trofimov, E. Efstathiadis, A. Steinmetz, Q. Peng, Yu. F. Orlov, P. von Walter, E. P. Solodov, D.N. Grigoriev, R. M. Carey, Yannis K. Semertzidis, Rasmus Larsen, Wuzheng Meng, H. Deng, A. Yamamoto, D. Nikas, D. Urner, G. T. Danby, D. Winn, J. M. Paley, R. Prigl, J. Mi, R. McNabb, S. K. Dhawan, V. P. Druzhinin, B. L. Roberts, F. Krinen, T. Qian, P. Cushman, Frederick Gray, C. J. G. Onderwater, J. Kindem, F. J. M. Farley, C. Ozben, P. T. Debevec, G. zu Putlitz, Yu. M. Shatunov, M. Deile, P. M. Shagin, S. I. Redin, X. Huang, E. P. Sichtermann, C. Timmermans, M. F. Hare, I. Kronkvist, B. Bousquet, O. Rind, I.B. Logashenko, B.I. Khazin, L. Duong, M. Kawamura, J. P. Miller, D. Warburton, M. Sossong, J. Pretz, D. Kawall, A. Grossmann, G. Bunce, Klaus-Peter Jungmann, Masahiko Iwasaki, V. W. Hughes, A. Lam, H. N. Brown, N.M. Ryskulov, S. Sedykh, M. Grosse-Perdekamp, G. W. Bennett, D. Zimmerman, William Deninger, L. R. Sulak, Y. Y. Lee, William Morse, D. W. Hertzog, S. Giron, and G.V. Fedotovich

Subjects
Physics, Particle physics, Muon, Anomalous magnetic dipole moment, General Physics and Astronomy, Charge (physics), Elementary particle, Electron, Nmr, Standard Model, Nuclear physics, Anomalous magnetic-moment, Positive muon, Storage ring, Lepton
Abstract

The measurement of the (g−2) value of leptons provides a unique test of theory since it is the only quantity (unlike charge and mass) calculable in the framework of the Standard Model of elementary particles. The muon (g−2) experiment E821 is currently in progress at Brookhaven National Laboratory. Four data taking runs for positive muons and one run for negative muons were successfully accomplished in 1997–2000 and 2001, respectively. Results of the 1997–2000 runs have been published, thus completing our experiment for μ+. Data analysis for the 2001 run for μ− is currently in progress. To provide measurement of \(a_\mu = \tfrac{1} {2}(g - 2)_{\mu ^ - }\) at the same level of accuracy as for \(a_{\mu ^ + } = \tfrac{1} {2}(g - 2)_{\mu ^ + }\), we need to have one more data taking run.

Published
2002

14. The superconducting inflector for the BNL g-2 experiment

Author

M. Mapes, H. N. Brown, L. X. Jia, E. P. Sichtermann, V. W. Hughes, H. Hseuh, William Morse, G. T. Danby, A. Grossmann, M Suenaga, W. B. Sampson, H Otsuka, D. Kawall, Klaus-Peter Jungmann, M G-Perdekamp, Y.Y. Lee, J. Pretz, B. L. Roberts, Y Tachiya, J. Sandberg, G. Bunce, C. Pai, H Tanaka, F. Krienen, Akira Yamamoto, T. Tallerico, K. Woodle, Y Saito, R. Prigl, S. K. Dhawan, H. Deng, T Ozawa, A. Steinmetz, Yasuhiro Makida, Wuzheng Meng, Kazuhiro Tanaka, I Itoh, G. zu Putlitz, S. I. Redin, F. Toldo, and Michael A. Green

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Muon, Anomalous magnetic dipole moment, Dipole magnet, Magnet, Superconducting magnet, Cryogenics, Instrumentation, Storage ring, Magnetic field
Abstract

The muon g-2 experiment at Brookhaven National Laboratory (BNL) has the goal of determining the muon anomalous magnetic moment, a μ (=( g- 2)/2) , to the very high precision of 0.35 parts per million and thus requires a storage ring magnet with great stability and homogeneity. A super-ferric storage ring has been constructed in which the field is to be known to 0.1 ppm . In addition, a new type of air core superconducting inflector has been developed and constructed, which successfully serves as the injection magnet. The injection magnet cancels the storage ring field, 1.5 T , seen by the entering muon beam very close to the storage ring aperture. At the same time, it gives negligible influence to the knowledge of the uniform main magnetic field in the muon storage region located at just 23 mm away from the beam channel. This was accomplished using a new double cosine theta design for the magnetic field which traps most of the return field, and then surrounding the magnet with a special superconducting sheet which traps the remaining return field. The magnet is operated using a warm-to-cold cryogenic cycle which avoids affecting the precision field of the storage ring. This article describes the design, research development, fabrication process, and final performance of this new type of superconducting magnet.

Published
2002

15. Muon g — 2 experiment at Brookhaven National Laboratory

Author

N.M. Ryskulov, L. Duong, C. Ozben, P. Cushman, F. Krienen, D.N. Grigoriev, H. N. Brown, Rasmus Larsen, Wuzheng Meng, Y.Y. Lee, P. von Walter, Yu. M. Shatunov, G.V. Fedotovich, H. Deng, M. Sossong, William Deninger, D. Winn, A. Grossmann, J. Pretz, E. P. Sichtermann, D. Urner, M. F. Hare, E. P. Solodov, R. M. Carey, C. Timmermans, William Morse, V. W. Hughes, F. J. M. Farley, Alexei Trofimov, R. Prigl, J. Mi, E. Efstathiadis, A. Steinmetz, D. Warburton, R. McNabb, D. Zimmerman, G. zu Putlitz, D. Kawall, S. I. Redin, D. Nikas, C. C. Polly, J. Kindem, Satish Dhawan, J. M. Paley, L. R. Sulak, Klaus-Peter Jungmann, J. P. Miller, B. L. Roberts, Masahiko Iwasaki, Yannis K. Semertzidis, G. T. Danby, C. J. G. Onderwater, M. Kawamur, V. P. Druzhinin, M. Deile, Frederick Gray, P. T. Debevec, A. Yamamoto, D. W. Hertzog, O. Rind, S. Giron, I. Kronkvist, Yuri F. Orlov, G. Bunce, B.I. Khazin, S. Sedykh, I. Logashenko, and M. Grosse-Perdekamp

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Muon, Alternating Gradient Synchrotron, National laboratory, Atomic and Molecular Physics, and Optics
Abstract

A precise measurement of the anomalous g value, a(mu)(+) = (g - 2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a(mu)(+) = 11 659 202(14)(6) x 10(-10) (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a(mu) (SM)= 11 659 159.6(6.7) x 10(-10) (0.57 ppm) and a(mu)(exp)-a(mu)(SM) = 42(16) x 10(-10) in which a(mu)(exp) is the world average experimental value.

Published
2002

16. Radial magnetic field measurements with a Hall probe device in the muon (g-2) storage ring magnet at BNL

Author

B.I. Khazin, G. T. Danby, P. von Walter, A. Grossmann, B. L. Roberts, William Morse, M. Grosse-Perdekamp, Yannis K. Semertzidis, F. J. M. Farley, G. Bunce, G. zu Putlitz, S. I. Redin, S. K. Dhawan, V. W. Hughes, J. W. Jackson, E. Efstathiadis, D. Kawall, Klaus-Peter Jungmann, N.M. Ryskulov, G.V. Fedotovich, and R. Prigl

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Muon, Hall effect, Magnet, Measure (physics), Orbit (dynamics), National laboratory, Instrumentation, Storage ring, Magnetic field
Abstract

A Hall probe device has been built to measure the radial component of the magnetic field in the muon (g-2) storage ring at Brookhaven National Laboratory. The ultraprecise (g-2) magnet provides a dominantly vertical magnetic field of about 1:45 T. In order to limit the vertical shift of the muon orbit, the average radial field component should be no more than 5 � 10 � 5 of the vertical field. Our measurements with the Hall probe device achieved an accuracy of 1 � 10 � 5 , which is one of the most precise measurements with Hall probes. This provides adequate accuracy for shimming and control of the radial field. # 2001 Elsevier Science B.V. All rights reserved.

Published
2001

17. Study of conversion decays φ→ηe+e−, η→e+e−γ and η→π+π−e+e− at CMD-2

Author

Alexander Valishev, M. Arpagaus, A.S. Kuzmin, V.A. Sidorov, N.I. Root, Igor Nesterenko, L.M. Kurdadze, M. Lechner, A.V. Otboev, A.A. Grebeniuk, P.Yu. Stepanov, B.A. Shwartz, V.M. Aulchenko, V.S. Okhapkin, A.G. Shamov, R.R. Akhmetshin, A.V. Bragin, A.S. Popov, V.Sh. Banzarov, V. W. Hughes, V.M. Titov, S.I. Eidelman, P.M. Ivanov, J. A. Thompson, S.G. Zverev, E. P. Solodov, K.Yu. Mikhailov, G.V. Fedotovitch, A.N. Skrinsky, Yu. M. Shatunov, N.M. Ryskulov, S.V. Karpov, Vassili Kazanin, Ivan Koop, A.L. Sibidanov, N.S. Bashtovoy, I.B. Logashenko, I.G. Snopkov, D.V. Bondarev, D.V. Chernyak, P.A. Lukin, A.I. Sukhanov, D.N. Grigoriev, P. Krokovny, A.A. Ruban, V.P. Smakhtin, Yu.V. Yudin, E.A. Perevedentsev, L.M. Barkov, E.V. Anashkin, T.A. Purlatz, F.V. Ignatov, N. Gabyshev, A.E. Bondar, and B.I. Khazin

Subjects
Physics, Nuclear and High Energy Physics, Meson, Electron–positron annihilation, Mass spectrum, Physical chemistry, Atomic physics
Abstract

Using 15.1 pb −1 of data collected by CMD-2 in the φ -meson energy range, the branching ratios of the following conversion decays have been measured: B ( φ → ηe + e − )=(1.14±0.10±0.06)×10 −4 , B ( η → e + e − γ )=(7.10±0.64±0.46)×10 −3 , B ( η → π + π − e + e − )=(3.7 +2.5 −1.8 ±0.3)×10 −4 . The upper limits for the following rare conversion decays have been obtained at the 90% confidence level: B ( φ → ημ + μ − ) −6 , B ( η → e + e − e + e − ) −5 .

Published
2001

18. [Untitled]

Author

J.F.C.A. Veloso, Satish Dhawan, Randolf Pohl, David Taqqu, F. Nez, Wolfgang Schott, Lukas A. Schaller, Yi-Wei Liu, Hubert Schneuwly, L. Julien, Paul E. Knowles, F. J. Hartmann, Paul Indelicato, C.A.N. Conde, Franz Kottmann, J.M.F. dos Santos, Paul Rabinowitz, W. Amir, S. Kazamias, O. Huot, F. Mulhauser, Theodor W. Hänsch, François Biraben, and V. W. Hughes

Subjects
Physics, Nuclear and High Energy Physics, Muon, Proton, Physics::Instrumentation and Detectors, Condensed Matter Physics, Laser, Atomic and Molecular Physics, and Optics, Lamb shift, law.invention, Nuclear physics, Root mean square, Charge radius, law, Physics::Atomic Physics, Physical and Theoretical Chemistry, Atomic physics, Spectroscopy, Lepton
Abstract

A measurement of the 2S Lamb shift in muonic hydrogen (µ − p) is being prepared at the Paul Scherrer Institute (PSI). The goal of the experiment is to measure the energy difference �E( 2 5 P3/2 − 2 3 S1/2) by laser spectroscopy (λ ≈ 6µm) to a precision of 30 ppm and to deduce the root mean square (rms) proton charge radius with 10 −3 relative accuracy, 20 times more precise than presently known. An important prerequisite to this experiment is the availability of long-lived µp2S -atoms. A 2S- lifetime of ∼1 µs - sufficiently long to perform the laser experiment - at H2 gas pressures of 1-2 hPa was deduced from recent measurements of the collisional 2S-quenching rate. A new low-energy negative muon beam yields an order of magnitude more muon stops in a small low-density gas volume than a conventional cloud muon beam. A stack of ultra-thin carbon foils is the key element of a fast detector for keV-muons. The development of a 2 keV X-ray detector and a 3-stage laser system providing 0.5 mJ laser pulses at 6 µ mi s on the way.

Published
2001

19. Observation of the φ→η′γ decay with four charged particles and photons in the final state

Author

A.S. Popov, A.V. Otboev, K.Yu. Mikhailov, Igor Nesterenko, V.S. Okhapkin, A.V. Bragin, E.A. Perevedentsev, P.Yu. Stepanov, Yu. M. Shatunov, V. W. Hughes, V.Sh. Banzarov, P.M. Ivanov, Ivan Koop, L.M. Barkov, E. P. Solodov, I.G. Snopkov, N.I. Root, Alexander Valishev, R.R. Akhmetshin, A.S. Kuzmin, Vassili Kazanin, N.S. Bashtovoy, D.V. Chernyak, V.M. Aulchenko, A.A. Ruban, F.V. Ignatov, P. Krokovny, S.V. Karpov, S.I. Redin, Yu.V. Yudin, A.L. Sibidanov, N.M. Ryskulov, G.V. Fedotovitch, M. Arpagaus, D.N. Grigoriev, A.A. Grebeniuk, A.G. Shamov, V.P. Smakhtin, J. A. Thompson, A.I. Sukhanov, S.I. Eidelman, D.V. Bondarev, B.A. Shwartz, S.G. Zverev, L.M. Kurdadze, A.N. Skrinsky, P.A. Lukin, M. S. Korostelev, V.A. Sidorov, T.A. Purlatz, N. Gabyshev, I.B. Logashenko, E.V. Anashkin, V.M. Titov, A.E. Bondar, and B.I. Khazin

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Photon, Branching fraction, Electron–positron annihilation, State (functional analysis), Decay chain, Atomic physics, Charged particle
Abstract

Using 11.6 pb −1 of data collected in the energy range 0.864-1.06 GeV by CMD-2 at VEPP-2M, the rare decay mode φ → η ′ γ was observed via the decay chain η ′→ π + π − η , η → π + π − π 0 or η → π + π − γ . The following branching ratio was obtained: Br(φ→η′γ)= 4.9 +2.2 −1.8 ±0.6 ×10 −5 .

Published
2000

20. Observation of the decay

Author

Alexander Valishev, I.G. Snopkov, N.I. Root, P.Yu. Stepanov, P.M. Ivanov, A.V. Bragin, V.Sh. Banzarov, Yu. M. Shatunov, N.M. Ryskulov, E. P. Solodov, Yu.V. Yudin, A.I. Sukhanov, B.I. Khazin, E.A. Perevedentsev, R.R. Akhmetshin, D.N. Grigoriev, Vassili Kazanin, S.V. Karpov, D.V. Chernyak, L.M. Barkov, A.L. Sibidanov, M. Arpagaus, F.V. Ignatov, V.P. Smakhtin, N.S. Bashtovoy, J. A. Thompson, A.V. Otboev, A.S. Popov, A.S. Kuzmin, I.B. Logashenko, G.V. Fedotovitch, V.S. Okhapkin, E.V Anashkin, V. W. Hughes, B.A. Shwartz, K.Yu. Mikhailov, M. S. Korostelev, A.A Ruban, A.N. Skrinsky, S.I. Eidelman, P.A. Lukin, P. Krokovny, A.E. Bondar, S.G. Zverev, Igor Nesterenko, V.A. Sidorov, T.A. Purlatz, L.M. Kurdadze, N. Gabyshev, I. A. Koop, S.I. Redin, A. I. Milstein, V.M. Titov, D.V. Bondarev, V.M. Aulchenko, A.A. Grebeniuk, and A.G. Shamov

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Crystallography, Annihilation, Pion, Meson, OZI rule, Branching fraction, Atomic physics
Abstract

Using 11.6 pb −1 of data collected in the energy range 0.984–1.06GeV by CMD-2 at VEPP-2M, the cross section of the reaction e + e − →π + π − π + π − hasbeen studied. For the firsttime an interference patternwas observed in the energy dependence of the cross section near theφ meson. The branching ratio of the φ → π + π − π + π − decay doublesuppressed by the G-parity and OZI rule is measuredBr(φ → π + π − π + π − ) = (3.93 ±1.74 ±2.14) ·10 −6 .The upper limits have been placed for the decays φ → π + π − π + π − π 0 and φ → ηπ + π − Br(φ → π + π − π + π − π 0 ) < 4.6 ·10 −6 90%CL,Br(φ → ηπ + π − ) < 1.8 ·10 −5 90%CL. 1 Introduction Production of four pions in e + e − annihilation is now well studied in the c.m.energy range 1.05 to 2.5 GeV (see [ 1] and references therein). Results onthe measurements of the cross section of the reaction e + e − → π + π − π + π − in the energy range from 0.60 to 0.97 GeV as well as the probability of theρ 0 meson decay into the π + π − π + π −

Published
2000

21. A quad 500 MHz waveform digitizer with differential trigger for use in the muon g-2 experiment

Author

D. Kawall, J. Pretz, Wen Liu, V. W. Hughes, Satish Dhawan, and R Sumner

Subjects
Physics, Nuclear and High Energy Physics, Muon, business.industry, Feature (computer vision), 8-bit, Waveform, Differential (infinitesimal), business, Instrumentation, Sample (graphics), Computer hardware, Communication channel
Abstract

We have developed and tested a 4 channel, 500 MHz, 512 k sample, 8 bit waveform digitizer in a FASTCAMAC module. A novel feature is the implementation of a sparse scan during readout with a programmable differential trigger to reduce the data to a manageable level. The differential trigger allows reliable detection of pulses with low threshold in the presence of a variable baseline.

Published
2000

22. Measurement of the1s−2sEnergy Interval in Muonium

Author

A. Breitrück, J. Merkel, Robin Santra, W. T. Toner, Simon L. Cornish, S. Reinhard, G. H. Eaton, Y Matyugin, Yakhontov, Klaus-Peter Jungmann, Yi-Wei Liu, GZ Putlitz, B Meyer, Christopher A. Scott, P E G Baird, D Hubl, A. Grossmann, SN Bagayev, P. Bakule, Lorenz Willmann, I. C. Lane, V. W. Hughes, S Dychkov, M. G. Boshier, D Lucas, P.G.H. Sandars, K. Träger, M. Towrie, and P. V. Schmidt

Subjects
Physics, Muon, Deuterium, Frequency separation, Muonium, Atom, Energy interval, General Physics and Astronomy, High Energy Physics::Experiment, Charge (physics), Physics::Atomic Physics, Atomic physics, Spectroscopy
Abstract

The 1s-2s interval has been measured in the muonium (;mgr;(+)e(-)) atom by Doppler-free two-photon pulsed laser spectroscopy. The frequency separation of the states was determined to be 2 455 528 941.0(9.8) MHz, in good agreement with quantum electrodynamics. The result may be interpreted as a measurement of the muon-electron charge ratio as -1-1.1(2.1)x10(-9). We expect significantly higher accuracy at future high flux muon sources and from cw laser technology.

Published
2000

23. New measurement of the rare decay φ→η′γ with CMD-2

Author

N.M. Ryskulov, A.I. Shekhtman, A.A. Grebeniuk, D.V. Bondarev, Alexander Valishev, A.G. Shamov, Igor Nesterenko, P.A. Lukin, A.S. Popov, V.A. Sidorov, L.M. Kurdadze, T.A. Purlatz, S.V. Karpov, A.S. Kuzmin, K.Yu. Mikhailov, E. P. Solodov, V.P. Smakhtin, N. Gabyshev, P. Krokovny, A.E. Bondar, A. P. Lysenko, V.Sh. Banzarov, J. A. Thompson, Yu. M. Shatunov, B.I. Khazin, D.N. Grigoriev, A.I. Sukhanov, Ivan Koop, M. Arpagaus, A.L. Sibidanov, I.G. Snopkov, V.M. Aulchenko, G.V. Fedotovitch, E.V. Anashkin, A.N. Skrinsky, M. S. Korostelev, A.A. Ruban, P.Yu. Stepanov, V.M. Titov, I.B. Logashenko, V. W. Hughes, B.A. Shwartz, N.I. Root, S.G. Zverev, N.S. Bashtovoy, Vassili Kazanin, A.V. Otboev, V.S. Okhapkin, A.V. Bragin, P.M. Ivanov, R.R. Akhmetshin, D.V. Chernyak, A.A. Polunin, Yu.V. Yudin, S.I. Eidelman, E.A. Perevedentsev, and L.M. Barkov

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), law, Branching fraction, Electron–positron annihilation, Detector, Collider, law.invention
Abstract

A new measurement of the rare decay φ → η ′ γ performed with the CMD-2 detector at the VEPP-2M collider in Novosibirsk is described. Of the data sample corresponding to the integrated luminosity of 14.5 pb −1 , twenty one events have been selected in the mode η ′→ π + π − η , η → γγ . The following branching ratio was obtained: B( φ → η ′ γ )=(8.2 +2.1 −1.9 ±1.1)·10 −5 .

Published
2000

24. Cross section of the reaction e+e−→π+π−π+π− below 1 GeV at CMD-2

Author

A.A. Polunin, A.V. Bragin, Igor Nesterenko, Alexander Valishev, S.V. Karpov, A.I. Sukhanov, A.E. Bondar, A. I. Milstein, E. P. Solodov, S.I. Eidelman, A.A. Grebeniuk, M. Arpagaus, N.M. Ryskulov, V.Sh. Banzarov, E.V. Anashkin, A.G. Shamov, A.L. Sibidanov, I.G. Snopkov, A.N. Skrinsky, A.S. Kuzmin, J. A. Thompson, M. S. Korostelev, I.B. Logashenko, Vassili Kazanin, V.A. Sidorov, R.R. Akhmetshin, B.A. Shwartz, V.M. Aulchenko, G.V. Fedotovitch, B.I. Khazin, V.M. Titov, S.G. Zverev, P.Yu. Stepanov, L.M. Kurdadze, N.I. Root, D.V. Bondarev, A.V. Otboev, P.A. Lukin, D.V. Chernyak, V.S. Okhapkin, T.A. Purlatz, N.S. Bashtovoy, N. Gabyshev, V. W. Hughes, Yu. M. Shatunov, Ivan Koop, A.S. Popov, K.Yu. Mikhailov, Yu.V. Yudin, L.M. Barkov, A.A. Ruban, P. Krokovny, V.P. Smakhtin, and D.N. Grigoriev

Subjects
Physics, Nuclear and High Energy Physics, Cross section (physics), Range (particle radiation), Meson, Branching fraction, Electron–positron annihilation, Intermediate state, Atomic physics
Abstract

Using 3.07 pb −1 of data collected in the energy range 0.60–0.97 GeV by CMD-2, about 150 events of the process e + e − → π + π − π + π − have been selected. The energy dependence of the cross section agrees with the assumption of the a 1 (1260) π intermediate state which is dominant above 1 GeV. For the first time π + π − π + π − events are observed at the ρ meson energy. Under the assumption that all these events come from the ρ meson decay, the value of the cross section at the ρ meson peak corresponds to the following decay width: Γ(ρ 0 →π + π − π + π − )=(2.8±1.4±0.5) keV or to the branching ratio B(ρ 0 →π + π − π + π − )=(1.8±0.9±0.3)·10 −5 .

Published
2000

25. [Untitled]

Author

P E G Baird, J. Merkel, Yi-Wei Liu, S Dychkov, WT Toner, Lorenz Willmann, D Hubl, Michael Towrie, Simon L. Cornish, I. C. Lane, P. V. Schmidt, V. W. Hughes, SN Bagayev, P. Bakule, S. Reinhard, A. Grossmann, K. Träger, D Lucas, Klaus-Peter Jungmann, Robin Santra, G. H. Eaton, M. G. Boshier, P.G.H. Sandars, Y Matyugin, Christopher A. Scott, B Meyer, G. zu Putlitz, A. Breitrück, and Yakhontov

Subjects
Hydrogen, Chemistry, Muonium, chemistry.chemical_element, Mass ratio, Lamb shift, symbols.namesake, Deuterium, Atom, symbols, High Energy Physics::Experiment, Physics::Atomic Physics, Atomic physics, Spectroscopy, Doppler effect
Abstract

The 1s–2s energy interval in the muonium (μ+e−) atom has been measured by Doppler free two photon laser spectroscopy. A value of 2455528941.0(9.8) MHz has been obtained in good agreement with quantum electrodynamics (QED). The muon-electron mass ratio can be extracted and is found to be 206.76838(17). The measurement may also be interpreted as a determination of the muon-electron charge ratio as -1- 1.1(2.1)· 10−9. Corresponding measurements in deuterium using the same experimental setup confirmed the validity of the applied analysis procedure.

Published
2000

26. [Untitled]

Author

Randolf Pohl, F. Trehin, Wolfgang Schott, O. Huot, Yi-Wei Liu, C. Petitjean, Paul E. Knowles, J.M.F. dos Santos, F. J. Hartmann, Hubert Schneuwly, L. M. Simons, C.A.N. Conde, V. W. Hughes, P. Hauser, David Taqqu, Françoise Mulhauser, Franz Kottmann, Theodor W. Hänsch, François Biraben, Paul Rabinowitz, J.F.C.A. Veloso, F. Nez, Paul Indelicato, and Lukas A. Schaller

Subjects
Physics, Muon, Proton, Physics::Instrumentation and Detectors, chemistry.chemical_element, Laser, law.invention, Lamb shift, Root mean square, Laser linewidth, Xenon, chemistry, law, Charge radius, Atomic physics
Abstract

The contribution of the root mean square (RMS) proton charge radius to the Lamb shift (2S–2P energy difference) in muonic hydrogen (μp) amounts to 2%. Apart from the uncertainty on this charge radius, theory predicts the Lamb shift with a precision on the ppm level. We are going to measure ΔE (2 S1/2(F=1)–2 P3/2(F=2)) in a laser resonance experiment to a precision of 30 ppm (i.e., 10% of the natural linewidth) and to deduce the RMS proton charge radius with 10−3 relative accuracy, 20 times more precise than presently known. The most important requirement for the feasibility of such an experiment, namely the availability of a sufficient amount of long lived metastable μp atoms in the 2S state, has been investigated in a recent experiment at PSI. Our analysis shows that in the order of one percent of all muons stopped in low pressure hydrogen gas form a long lived μp(2S) with a lifetime of the order of 1 μs. The technical realization of our experiment involves a new high intensity low energy muon beam, an efficient low energy muon entrance detector, a randomly triggered 3 stage laser system providing the 0.5 mJ, 7 ns laser pulses at 6.02 μm wavelength, and a combination of a xenon gas proportional scintillation chamber (GPSC) and a microstrip gas chamber (MSGC) with a CsI coated surface to detect the 2 keV X rays from theμp(2P → 1S) transition.

Published
2000

27. Study of the radiative decay φ→ηγ with CMD-2 detector

Author

P.A. Lukin, V.P. Smakhtin, N. Gabyshev, J. A. Thompson, P.Yu. Stepanov, I.B. Logashenko, S.I. Eidelman, D.V. Bondarev, A.A. Ruban, T.A. Purlatz, L.M. Kurdadze, I.G. Snopkov, N.I. Root, N.S. Bashtovoy, G.V. Fedotovich, A.I. Sukhanov, D.N. Grigoriev, B.A. Shwartz, Yu.V. Yudin, V. W. Hughes, S.G. Zverev, V. S. Banzarov, A. Bondar, A. P. Lysenko, L.M. Barkov, R.R. Akhmetshin, D.V. Chernyak, A.A. Grebeniuk, B.I. Khazin, A.G. Shamov, E.V. Anashkin, B. L. Roberts, A.N. Skrinsky, A.S. Kuzmin, Yu. M. Shatunov, P.M. Ivanov, Ivan Koop, P. Krokovny, K.Yu. Mikhailov, V.A. Sidorov, N.M. Ryskulov, V.S. Okhapkin, E. P. Solodov, and Vassili Kazanin

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Branching fraction, Detector, Mode (statistics), Radiative decay
Abstract

Using the 1.9 pb −1 of data collected with the CMD-2 detector at VEPP-2M the decay mode φ→ηγ, η→π+π−π0 has been studied. The obtained branching ratio is B(φ→ηγ)=(1.18±0.03±0.06)%.

Published
1999

28. Status of the BNL muon (g-2) experiment

Author

W.M. Morse, S. I. Serednyakov, Yu. M. Shatunov, S. Sedykh, C. J. G. Onderwater, N.M. Ryskulov, A. Yamamoto, Lawrence Sulak, O. Rind, C. Timmermans, F. J. M. Farley, M. Sossong, P. Neumayer, H. N. Brown, G. zu Putlitz, D. Urner, S. I. Redin, W. Meng, J. Pretz, I. Kronkvist, P. T. Debevec, E. Hazen, L. Duong, E. Efstathiadis, J. Kindem, Yuri F. Orlov, S. K. Dhawan, J. P. Miller, D. W. Hertzog, M. Tanaka, V. W. Hughes, Frederick Gray, G.T. Danby, Robert Sanders, D. Miller, F. Krienen, Y.Y. Lee, Wen Liu, Klaus-Peter Jungmann, W. Earle, Masahiko Iwasaki, G. Bunce, B.I. Khazin, M. Grosse Perdekamp, M. Kawamura, D. Zimmerman, P. Cushman, C. Pai, D. Warburton, C. C. Polly, H. Deng, D. Winn, A. Grossmann, E. P. Solodov, R. M. Carey, William Deninger, M. F. Hare, G.V. Fedotovich, I.B. Logashenko, R. Prigl, J. Mi, R. McNabb, D. Kawall, Alexei Trofimov, A. Steinmetz, V. P. Druzhinin, B. L. Roberts, S. Giron, Yannis K. Semertzidis, R. Larsen, and Ulrich Haeberlen

Subjects
Larmor precession, Physics, Particle physics, Large Hadron Collider, Muon, Muon storage ring, Meson, Proton, Physics::Instrumentation and Detectors, Electron, Superconducting coils, G factor, Nuclear magnetic resonance, Nuclear physics, Physics::Accelerator Physics, High Energy Physics::Experiment, Supersymmetry, Electrical and Electronic Engineering, Spin precession, Superconducting Coils, Instrumentation, Storage ring, Standard model
Abstract

The muon (g-2) experiment at Brookhaven completed a first run in June and July 1997. The main components of the experiment, which include the superconducting inflector, the superferric storage ring, the electrostatic quadrupoles and the lead-scintillating fiber electron calorimeters, have been commissioned satisfactorily. Our first measurement of the ratio R of the spin precession frequency of the positive muon relative to that of a free proton, R=(3.707219/spl plusmn/0.000048)/spl times/10/sup -3/, is in good agreement with the previous CERN measurements for /spl mu//sup +/ and /spl mu//sup -/, and has approximately the same uncertainty as each of these measurements. In spring 1998 a muon kicker was installed and successfully tested in the storage ring magnet and a significant improvement in the knowledge of the muon g-factor is expected from upcoming runs in August 1998 and January 1999.

Published
1999

29. Status of the g-2 experiment at BNL

Author

D. Kawall, V. B. Golubev, S. Kurokawa, E. P. Solodov, B. J. Hughes, G. Bunce, P. Cushman, P. von Walter, R. M. Carey, A. Stillman, P. T. Debevec, Y.Y. Lee, J. W. Jackson, G.V. Fedotovich, Louis Snydstrup, F. Toldo, A.G. Chertovskikh, Rasmus Larsen, H. Hirabayashi, J. Cullen, M. F. Hare, O. Rind, H. Deng, D. von Lintig, E. Benedict, D. Urner, David Miller, Alexei Trofimov, X. Fei, J. Benante, A. Disco, D. Winn, A. Soukas, E. Efstathiadis, F. J. M. Farley, Yannis K. Semertzidis, R. Prigl, H. N. Brown, R. McNabb, O. N. Ryskulov, Yuri Shatunov, C. Timmermans, Jinsong Ouyang, J. Geller, William Deninger, G. zu Putlitz, S. I. Redin, M. Tanaka, K. Woodle, C. Poly, E. Hazen, B. Bunker, C. Pearson, Y. Mizumachi, M. Grosse Perdekamp, H. E. Ahn, Ulrich Haeberlen, J. Pretz, K. Endo, D. Zimmerman, V. Monich, L. Jia, G. T. Danby, R. P. Shutt, J. Kindem, William Morse, T. D. Jones, A. Maskimov, L. Duong, H. Hseuh, V. P. Druzhinin, S. I. Serednyakov, F. Krienen, Wuzheng Meng, B.I. Khazin, C. Pai, Yuri F. Orlov, Michael A. Green, W. Earle, M. Mapes, A. Grossmann, V. W. Hughes, D. Warbuton, Yu Merzliakov, I. Polk, Satish Dhawan, J. Gerhaeuser, W. A. Worstell, S. Kochis, J. P. Miller, B. L. Roberts, Klaus-Peter Jungmann, Masahiko Iwasaki, J. Sandberg, S. Sedykh, S. Rankowitz, D.H Brown, D. N. Grigorev, I. Logashenko, G. S. Varner, D. W. Hertzog, A. Yamamoto, T. Tallerico, S. Giron, L. R. Sulak, and Precision Frontier

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Large Hadron Collider, Muon, Meson, Anomalous magnetic dipole moment, Physics::Instrumentation and Detectors, MUON, Atomic and Molecular Physics, and Optics, Nuclear physics, Pion, DIPOLE-MOMENT, Antimatter, Physics::Accelerator Physics, High Energy Physics::Experiment, ANOMALOUS MAGNETIC-MOMENT, Storage ring, Lepton
Abstract

The muon g-2 experiment at Brookhaven has successfully completed two exploratory runs using pion injection and direct muon injection for checkout and initial data taking. The main components of the experiment, which include the pion beam line, the superconducting storage ring and inflector magnets, the muon kicker and the lead-scintillating fiber calorimeters have been satisfactorily commissioned. First results on the anomalous magnetic moment of the positive muon from pion injection are in good agreement with previous experimental results for a(mu+) and a(mu-) from CERN and of comparable accuracy (13 ppm). Analysis of the 1998 muon injection run is in progress and expected to improve the precision to about 4 ppm. A first production run is scheduled for January 1999 with the goal of reaching the 1 ppm error level.

Published
1999

30. Anomalousgvalues of the electron and muon

Author

V. W. Hughes and T. Kinoshita

Subjects
Physics, Muon, Quantum electrodynamics, General Physics and Astronomy, Electron, Atomic physics, Spectroscopy, Spin (physics), Electron magnetic dipole moment, Hyperfine structure, Lamb shift, Spin magnetic moment
Abstract

Historically, the spin magnetic moment of the electron µ e or its gvalue g e has played a central role in modern physics, dating from its discovery in atomic optical spectroscopy and its subsequent incorporation in the Dirac theory of the electron, which predicted the value g e = 2 The experimental discovery in atomic microwave spectroscopy that g e was larger than 2 by a multiplicative factor of about 1 part in 103, g e =2.00238(10), together with the discovery of the Lamb shift in hydrogen (S=22 S 1/2 − 22 P 1/2), led to the development of modern quantum electrodynamics with its renormalization procedure. The theory enables us to calculate these effects precisely as finite radiative corrections. By now the experimental value of g e -2has been measured to about 4 ppb, and the theoretical value, which is expressed as a power series in the fine-structure constant a, has been evaluated to better than 1 ppb, assuming the value of α is known.

Published
1999

31. Study of dynamics of φ→π+π−π0 decay with CMD-2 detector

Author

V.A. Sidorov, A.I. Sukhanov, V.I Ptitzyn, D.N. Grigoriev, P.M. Ivanov, B.I. Khazin, V. W. Hughes, Yu. M. Shatunov, D.H Brown, N.I. Root, S.G. Zverev, N.M. Ryskulov, T.A. Purlatz, Ivan Koop, G.V. Fedotovich, S. Eidelman, Igor Nesterenko, B. L. Roberts, A.A. Polunin, L.M. Kurdadze, V.S. Okhapkin, I.G. Snopkov, B.O Baibusinov, J. A. Thompson, A.S. Dvoretsky, Yu.I Merzlyakov, E.V. Anashkin, I.B. Logashenko, G.A Aksenov, A.N. Skrinsky, M. Arpagaus, P.Yu. Stepanov, R.R. Akhmetshin, P.A. Lukin, N. Gabyshev, V.M. Titov, B. Shwartz, V.P. Smakhtin, A.A. Ruban, Yu.V. Yudin, A. Bondar, L.M. Barkov, V. S. Banzarov, V.V Danilov, E. P. Solodov, A.A. Grebeniuk, A.S. Kuzmin, D.V. Chernyak, and A.G. Shamov

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Amplitude, Meson, law, Electron–positron annihilation, Detector, Dalitz plot, Atomic physics, Collider, law.invention
Abstract

A study of the φ → π + π − π 0 decay mode has been performed using a data sample of about 2.0 million φ decays collected by the CMD-2 detector at VEPP-2M collider in Novosibirsk. The following parameters of the φ -meson have been measured: Br ( φ → π + π − π 0 )=0.145±0.009±0.003 and δ φ − ω =162±17°. The analysis of the Dalitz plot showed the dominance of the φ → ρπ intermediate mechanism, the limits for the ratio of the direct amplitude of φ →3 π to that of φ → ρπ are −0.16 a 1 φ → π + π − η and direct φ → ργγ have been found for the first time: Br ( φ → π + π − η ) −4 and Br ( φ → ργγ ) −4 at 90% C.L.

Published
1998

32. Polarised quark distributions in the nucleon from semi-inclusive spin asymmetries

Author

F. Tessarotto, F. Perrot-Kunne, W. Kröger, E. Burtin, K. Zaremba, Jay Roberts, J. Cranshaw, T. Matsuda, M. Plo, I. Sabo, M. Grosse Perdekamp, A. Karev, K. Haft, V. G. Krivokhijine, S. K. Dhawan, J. Lichtenstadt, S. Platchkov, N. de Botton, Victor Kukhtin, H. Gilly, M. Lamanna, J. H. Moromisato, Clemens A. Heusch, J. S. McCarthy, G. Igo, A. Steinmetz, Patrick Hautle, S. Bültmann, R. Birsa, F. Feinstein, D. von Harrach, J. E.J. Oberski, Takahiro Iwata, A. Ogawa, A. Schiller, D. Thers, Yu. Kisselev, G. Reicherz, D. Crabb, J. A. Garzon, C. Dulya, Naoaki Horikawa, Franco Bradamante, T. Akdogan, B. Roscherr, S. Dalla Torre, H. J. Kessler, G. Bardin, L. Betev, Roland Windmolders, J. Martino, Abhay Deshpande, C. S. Özben, M. Velasco, A. Arvidson, Rudiger Voss, J. Nassalski, M. Giorgi, U. Stiegler, T. Hasegawa, I.A. Savin, D. J. Miller, P. Schiavon, Andrea Bressan, Michal Szleper, A. Gallas, G. K. Mallot, J. Vogt, E. Arik, B. W. Mayes, T. O. Niinikoski, S. Ishimoto, Lawrence Pinsky, A. Witzmann, Y. Miyachi, St. Goertz, F. Lehar, G. Unel, B. Frois, H. Postma, R. van Dantzig, Matias Rodriguez, E. P. Sichtermann, F. Simeoni, G.I. Smirnov, J. Saborido, R. Puntaferro, D. Fasching, G. van Middelkoop, Jinkui Zhao, D. Pose, W. Meyer, Kunikazu Mori, C. A. Whitten, J. Kyynäräinen, A. de Lesquen, J. Pretz, K. Medved, Regine Willumeit, H. Pereira, W. Tlaczala, A. Tripet, G. Gracia, A. Sandacz, N. De Groot, K. Kurek, Anna Zanetti, F. Marie, T. Kageya, A. Rijllart, Bernardo Adeva, E. Rondio, T. Çuhadar, J. M. Le Goff, Heinrich B. Stuhrmann, A. Magnon, J. Ylöstalo, L. Naumann, M. Litmaath, Günter Baum, P. Berglund, B. Derro, E. von Goeler, D. Krämer, W. Wislicki, G. Rädel, S. Eichblatt, Alan D. Martin, B. Badelek, C. Fernandez, N. Hayashi, D. Peshekhonov, A. Bravar, V. W. Hughes, Ulrich Landgraf, A. Staude, T. J. Ketel, S. Forthmann, J. Kiryluk, E. M. Kabuß, (Astro)-Particles Physics, B., Adeva, T., Akdogan, E., Arik, A., Arvidson, B., Badelek, G., Bardin, G., Baum, P., Berglund, L., Betev, R., Birsa, N., de Botton, Bradamante, Franco, A., Bravar, Bressan, Andrea, S., Bültmann, E., Burtin, D., Crabb, J., Cranshaw, T., Çuhadar, DALLA TORRE, Silvia, R., van Dantzig, B., Derro, A., Deshpande, S., Dhawan, C., Dulya, S., Eichblatt, D., Fasching, F., Feinstein, C., Fernandez, S., Forthmann, B., Froi, A., Galla, J. A., Garzon, H., Gilly, Giorgi, Marcello, E., von Goeler, S., Goertz, G., Gracia, N., de Groot, M., Grosse Perdekamp, K., Haft, D., von Harrach, T., Hasegawa, P., Hautle, N., Hayashi, C. A., Heusch, N., Horikawa, V. W., Hughe, G., Igo, S., Ishimoto, T., Iwata, E. M., Kabuß, T., Kageya, A., Karev, H. J., Kessler, T. J., Ketel, J., Kiryluk, Kisselev, Y. u., D., Krämer, V., Krivokhijine, W., Kröger, V., Kukhtin, K., Kurek, J., Kyynäräinen, M., Lamanna, U., Landgraf, J. M., Le Goff, F., Lehar, A., de Lesquen, J., Lichtenstadt, M., Litmaath, A., Magnon, G. K., Mallot, F., Marie, Martin, Anna, J., Martino, T., Matsuda, B., Maye, J. S., Mccarthy, K., Medved, W., Meyer, G., van Middelkoop, D., Miller, Y., Miyachi, K., Mori, J., Moromisato, J., Nassalski, L., Naumann, T. O., Niinikoski, J. E. J., Oberski, A., Ogawa, C., Ozben, H., Pereira, F., Perrot Kunne, D., Peshekhonov, L., Pinsky, S., Platchkov, M., Plo, D., Pose, H., Postma, J., Pretz, R., Puntaferro, G., Rädel, A., Rijllart, G., Reicherz, J., Robert, M., Rodriguez, E., Rondio, B., Roscherr, I., Sabo, J., Saborido, A., Sandacz, I., Savin, Schiavon, Paolo, A., Schiller, E. P., Sichtermann, F., Simeoni, G. I., Smirnov, A., Staude, A., Steinmetz, U., Stiegler, H., Stuhrmann, M., Szleper, F., Tessarotto, D., Ther, W., Tlaczala, A., Tripet, G., Unel, M., Velasco, J., Vogt, R., Vo, C., Whitten, R., Windmolder, R., Willumeit, W., Wislicki, A., Witzmann, J., Ylöstalo, Zanetti, ANNA MARIA, K., Zaremba, and J., Zhao

Subjects
Quark, Physics, Nuclear and High Energy Physics, Particle physics, Muon, Valence (chemistry), SMC, Hadron, FOS: Physical sciences, SIDIS, Polarized quark distributions, Deep inelastic scattering, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), Deuterium, High Energy Physics::Experiment, Nucleon, Particle Physics - Experiment
Abstract

We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003$1 GeV$^2$. Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at $Q^2$=10 GeV$^2$. The polarised $u$ valence quark distribution, $\Delta u_v(x)$, is positive and the polarisation increases with $x$. The polarised $d$ valence quark distribution, $\Delta d_v(x)$, is negative and the non-strange sea distribution, $\Delta \bar q(x)$, is consistent with zero over the measured range of $x$. We find for the first moments $\int_0^1 \Delta u_v(x) dx = 0.77 \pm 0.10 \pm 0.08$, $\int_0^1 \Delta d_v(x) dx = -0.52 \pm 0.14 \pm 0.09$ and $\int_0^1 \Delta \bar q(x) dx= 0.01 \pm 0.04 \pm 0.03$, where we assumed $\Delta \bar u(x) = \Delta \bar d(x)$. We also determine for the first time the second moments of the valence distributions $\int_0^1 x \Delta q_v(x) dx$., Comment: 17 pages

Published
1998

33. Search for rare φ decays in π+π−γ final state

Author

D.H Brown, M.A Shubin, S.I. Eidelman, Igor Nesterenko, P.M. Ivanov, B.O Baibusinov, V.A. Sidorov, N.I. Root, E.V Popkov, L.M. Kurdadze, I.G. Snopkov, G.V. Fedotovich, V. S. Banzarov, I.B. Logashenko, V.P. Smakhtin, E. P. Solodov, B.I. Khazin, A. Bondar, L.M. Barkov, B.A. Shwartz, B.L. Roberts, C.M Valine, Yu.V. Yudin, R.R. Akhmetshin, M. Arpagaus, A.V Maksimov, I. A. Koop, G.A Aksenov, V. W. Hughes, T.A. Purlatz, Yu.I Merzlyakov, N.M. Ryskulov, V.M. Titov, Alexander Skrinsky, V.S. Okhapkin, E.A. Perevedentsev, A.A. Ruban, J. A. Thompson, E.V Anashkin, V. A. Astakhov, A.A. Grebeniuk, P.A. Lukin, D.N. Grigoriev, N. Gabyshev, A.I. Sukhanov, A.S. Kuzmin, A.P. Lysenko, and D.V. Chernyak

Subjects
Physics, Nuclear and High Energy Physics, Crystallography, Bremsstrahlung, State (functional analysis), Atomic physics
Abstract

A search for φ radiative decays has been performed using a data sample of about 2.0 million φ decays collected by the CMD-2 detector at VEPP-2M collider in Novosibirsk. From the selected e + e − → π + π − γ events the following results were obtained: B( φ → f 0 (980) γ ) −4 for destructive and B( φ → f 0 (980) γ ) −4 for constructive interference with the Bremsstrahlung process respectively, B( φ → γ → π + π − γ ) −5 for E γ >20 MeV, B( φ → ργ ) −4 . From the selected e + e − → μ + μ − γ events B( φ → μ + μ − γ )=(2.3±1.0)×10 −5 has been obtained for E γ >20 MeV. The upper limit on the P,CP-violating decay η → π + π − has also been placed: B( η → π + π − ) −4 . All upper limits are at 90% C.L.

Published
1997

34. First observation of the decay φ→η′(958)γ

Author

E.V Popkov, E.V Anashkin, B.I. Khazin, P.Yu. Stepanov, D.H Brown, M.A Shubin, V.V Danilov, Yu. M. Shatunov, N.M. Ryskulov, V.P. Smakhtin, A.I. Sukhanov, A.I. Shekhtman, A.P. Lysenko, V.I Ptitzyn, S.I. Eidelman, B.A. Shwartz, M. Arpagaus, T.A. Purlatz, A.A. Grebeniuk, A. V. Klimenkov, P.M. Ivanov, S.G. Zverev, N.I. Root, A.A. Polunin, G.V. Fedotovich, A.G. Shamov, V. W. Hughes, A.A. Ruban, S.E Baru, E. P. Solodov, D.N. Grigoriev, I.B. Logashenko, J. A. Thompson, P.A. Lukin, E.A. Perevedentsev, A.S. Kuzmin, A.G. Chertovskikh, A. Bondar, L.M. Barkov, Yu.V. Yudin, R.R. Akhmetshin, V.A. Sidorov, Vassili Kazanin, V. S. Banzarov, D.V. Chernyak, V.M Aulchenko, Alexander Skrinsky, I. A. Koop, A.V Maksimov, V.S. Okhapkin, B.L. Roberts, N. Gabyshev, L.M. Kurdadze, I.G. Snopkov, and A.S. Dvoretsky

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, law, Branching fraction, Radiative decay, Collider, Event (particle physics), law.invention
Abstract

The decay φ → η ′ γ has been observed by the CMD-2 detector at the e + e − collider VEPP-2M at Novosibirsk. Of 5.5 million produced φ 's, six events of the φ → η ′ γ decay were selected with the expected background less than one event. The corresponding branching ratio is B( φ → η ′ γ )=1.2 +0.7 −0.5 ·10 −4 . It is the first observation of this radiative decay.

Published
1997

35. The spin-dependent structure function g1(x) of the proton from polarized deep-inelastic muon scattering

Author

Michal Szleper, D. Crabb, Heinrich B. Stuhrmann, A. Schiller, Naoaki Horikawa, J. Pretz, A. Rijllart, Bernardo Adeva, T. Kageya, J. Ylöstalo, A. Ogawa, L. Naumann, C. Dulya, I. Sabo, C. A. Whitten, J. Kyynäräinen, A. Tripet, D. Peshekhonov, F. Lehar, V. W. Hughes, G. Gracia, P. Schiavon, A. Sandacz, M. Giorgi, V. G. Krivokhijine, B. Mayes, Rudiger Voss, Yu. Kisselev, S. K. Dhawan, B. Derro, J. S. McCarthy, S. Bültmann, T. O. Niinikoski, Ulrich Landgraf, E. Arik, Alan D. Martin, F. Marie, A. Staude, M. Litmaath, Etienne Burtin, David Miller, Matias Rodriguez, Kunikazu Mori, J. Moromisato, A. Magnon, D. Thers, E. P. Sichtermann, K. Kurek, E. M. Kabuß, E. Rondio, D. Pose, Abhay Deshpande, K. Zaremba, I.A. Savin, T. J. Ketel, M. Plo, F. Feinstein, A. Karev, Matthias Grosse Perdekamp, G. Bardin, A. Witzmann, Patrick Hautle, J. M. Le Goff, G. Igo, J. Kiryluk, Clemens A. Heusch, T. Çuhadar, S. Platchkov, J. Lichtenstadt, R. Birsa, J. A. Garzon, Franco Bradamante, W. Wislicki, A. Steinmetz, P. Berglund, K. Medved, N. De Groot, Anna Zanetti, H. Postma, B. Frois, J. Saborido, W. Tlaczala, B. Roscherr, Lawrence Pinsky, T. Matsuda, S. Ishimoto, U. Stiegler, H. Gilly, G. Unel, F. Simeoni, G.I. Smirnov, R. van Dantzig, R. Puntaferro, J. E.J. Oberski, J. Nassalski, G. van Middelkoop, G. Rädel, W. Meyer, B. Badelek, C. Fernandez, Mayda Velasco, N. Hayashi, L. Betev, F. Perrot-Kunne, S. Eichblatt, A. Bravar, V. Kuktin, J. Cranshaw, D. Fasching, J. Vogt, G. Baum, Takahiro Iwata, G. Reicherz, Roland Windmolders, S. Dalla Torre, A. Arvidson, H. Pereira, A. de Lesquen, St. Goertz, N. de Botton, Andrea Bressan, J. Martino, A. Gallas, G. K. Mallot, Y. Miyachi, M. Lamanna, S. Forthmann, K. Haft, F. Tessarotto, W. Kröger, B., Adeva, E., Arik, A., Arvidson, B., Badelek, G., Bardin, G., Baum, P., Berglund, L., Betev, Birsa, Renato, N., de Botton, Bradamante, Franco, A., Bravar, Bressan, Andrea, S., Bültmann, E., Burtin, D., Crabb, J., Cranshaw, T., Çuhadar, DALLA TORRE, Silvia, R., van Dantzig, B., Derro, A., Deshpande, S., Dhawan, C., Dulya, S., Eichblatt, D., Fasching, F., Feinstein, C., Fernandez, S., Forthmann, B., Froi, A., Galla, J. A., Garzon, H., Gilly, Giorgi, Marcello, S., Goertz, G., Gracia, N., de Groot, K., Haft, D., von Harrach, T., Hasegawa, P., Hautle, N., Hayashi, C. A., Heusch, N., Horikawa, V. W., Hughe, G., Igo, S., Ishimoto, T., Iwata, E. M., Kabuß, T., Kageya, A., Karev, T. J., Ketel, J., Kiryluk, Kisselev, Y. u., V., Krivokhijine, W., Kröger, V., Kuktin, K., Kurek, J., Kyynäräinen, M., Lamanna, U., Landgraf, J. M., Le Goff, F., Lehar, A., de Lesquen, J., Lichtenstadt, M., Litmaath, A., Magnon, G. K., Mallot, F., Marie, Martin, Anna, J., Martino, T., Matsuda, B., Maye, J. S., Mccarthy, K., Medved, W., Meyer, G., van Middelkoop, D., Miller, Y., Miyachi, K., Mori, J., Moromisato, J., Nassalski, L., Naumann, T. O., Niinikoski, J. E. J., Oberski, A., Ogawa, M., Perdekamp, H., Pereira, F., Perrot Kunne, D., Peshekhonov, L., Pinsky, S., Platchkov, M., Plo, D., Pose, H., Postma, J., Pretz, R., Puntaferro, G., Rädel, A., Rijllart, G., Reicherz, M., Rodriguez, E., Rondio, B., Roscherr, I., Sabo, J., Saborido, A., Sandacz, I., Savin, Schiavon, Paolo, A., Schiller, E. P., Sichtermann, F., Simeoni, G. I., Smirnov, A., Staude, A., Steinmetz, U., Stiegler, H., Stuhrmann, M., Szleper, F., Tessarotto, D., Ther, W., Tlaczala, A., Tripet, G., Unel, M., Velasco, J., Vogt, R., Vo, C., Whitten, R., Windmolder, W., Wislicki, A., Witzmann, J., Ylöstalo, Zanetti, ANNA MARIA, K., Zaremba, and (Astro)-Particles Physics

Subjects
Physics, Quantum chromodynamics, DIS, Nuclear and High Energy Physics, Particle physics, Muon, Proton, SMC, Scattering, g1 structure function, Perturbative QCD, Deep inelastic scattering, Nuclear physics, Sum rule in quantum mechanics, Nucleon, Particle Physics - Experiment
Abstract

We present a new measurement of the virtual photon proton asymmetry $A_1^{\rm p}$ from deep inelastic scattering of polarized muons on polarized protons in the kinematic range $0.0008 < x < 0.7$ and $0.2 < Q^{2} < 100$ GeV$^{2}$. With this, the statistical uncertainty of our measurement has improved by a factor of $2$ compared to our previous measurements. The spin-dependent structure function $g_{1}^{\rm p}$ is determined for the data with $Q^{2} > 1$ GeV$^{2}$. A perturbative QCD evolution in next-to-leading order is used to determine $g_1^{\rm p}(x)$ at a constant $Q^2$. At $Q^{2} = 10$ GeV$^{2}$ we find, in the measured range, $\int_{0.003}^{0.7} g_{1}^{\rm p}(x){\rm d}x = 0.139 \pm 0.006~({\rm stat})\pm 0.008~({\rm syst)} \pm 0.006~({\rm evol})$. The value of the first moment $\Gamma_{1}^{\rm p} = \int_{0}^{1} g_{1}^{\rm p}(x){\rm d}x$ of $g_{1}^{\rm p}$ depends on the approach used to describe the behaviour of $g_{1}^{\rm p}$ at low $x$. We find that the Ellis-Jaffe sum rule is violated. With our published result for $\Gamma_{1}^{\rm d}$ we confirm the Bjorken sum rule with an accuracy of $\approx 15\%$ at the one standard deviation level.

Published
1997

36. Precision measurement of the magnetic field in terms of the free-proton NMR frequency

Author

V. W. Hughes, Ralf Prigl, and Xiang Fei

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Accuracy and precision, Range (particle radiation), Field (physics), Proton NMR, Experimental methods, Instrumentation, Water sample, Magnetic field, Computational physics
Abstract

We have developed a NMR standard probe using a spherical pure water sample of 1 cm diameter to determine the absolute magnetic field B in terms of the free-proton NMR frequency fp with an accuracy of 3.4 × 10−8. Our standard probe can be used conveniently to calibrate other probes in the field range from 1.45 to 1.7 T and can readily be employed over a much wider field range. The probe design and the tests carried out to verify its precision and accuracy are presented.

Published
1997

37. Test results of the g-2 superconducting solenoid magnet system

Author

L. X. Jia, R. P. Shutt, N.M. Ryskulov, Louis Snydstrup, B. L. Roberts, Y. Semertzidas, Martin A. Green, H. Hirabayashi, H. Hseuh, T. Tallerico, D. Kawall, Akira Yamamoto, G.V. Fedotovich, I. Polk, J. Cullen, Ulrich Haeberlen, Rasmus Larsen, P. von Walter, K. Endo, G. T. Danby, S.I. Redin, C. Pai, R. Prigl, M. Grosse-Perdckamp, F. Krienen, J. Geller, J. W. Jackson, Wuzheng Meng, V. W. Hughes, GZ Putlitz, Gerry Bunce, B. I. Khazin, Klaus-Peter Jungmann, K. A. Woodle, William Morse, A. Grossmann, J. Benante, and Precision Frontier

Subjects
Physics, Physics::Instrumentation and Detectors, Solenoid, Superconducting magnet, Mechanics, Cryogenics, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Dipole, Nuclear magnetic resonance, Dipole magnet, Magnet, Physics::Accelerator Physics, Electrical and Electronic Engineering, Magnetic dipole, Yoke
Abstract

The g-2 experiment dipole consists of a single 48 turn, 15.1 meter diameter outer solenoid and a pair of 24 turn inner solenoids, 13.4 meters in diameter. The inner solenoids are hooked in series and are run at a polarity that is opposite that of the outer solenoid, thus creating a dipole field in the space between the inner and outer solenoids. The dipole flux is returned by a C shaped continuous iron yoke. The superconducting solenoid coils are closely coupled to the solenoid mandrels and as such are subject to quench back. This report presents the results of various tests on the g-2 magnet system operating within its iron return yoke. These tests include quench back time constant measurements for the inner and outer solenoids and measurements of the response of the two-phase forced cooled helium cryogenic system to magnet quenches. The overall effectiveness of the g-2 magnet quench protection system was measured.

Published
1997

38. The spin-dependent structure function g1(x) of the deuteron from polarized deep-inelastic muon scattering

Author

S. Bültmann, T. Kageya, M. Boutemeur, D. Fasching, T. Pussieux, A. Bressan, J. E.J. Oberski, E. M. Kabuß, E. Burtin, T. Matsuda, D.V. Peshekhonov, K. M. Teichert, I. Sabo, Jay Roberts, I.A. Savin, V. G. Krivokhijine, J. Nassalski, J. Zhao, N. de Botton, Victor Kukhtin, A. Bravar, B. W. Mayes, E. Arik, R. Seitz, G. Gratia, W. Tlaczala, J. Cranshaw, H. J. Kessler, Roland Windmolders, M. Lowe, A. Arvidson, J. Martino, A. Gallas, A. Nagaitsev, G. K. Mallot, M. Lamanna, Y. Ylöstalo, David Miller, Aina Yañez, G. Bardin, Drew Parks, L. Naumann, G. Unel, T. O. Niinikoski, J. Lichtenstadt, J. Kyynäräinen, F. Tessarotto, W. Kröger, H. Postma, J. Kiryluk, J. Saborido, M. Litmaath, L. S. Pinsky, P. Schiavon, N. Horikawa, B. Derro, D. von Harrach, M. K. Ballintijn, D. Krämer, Abhay Deshpande, F. Sever, R. Puntaferro, K. P. Schüler, E. Rondio, J. H. Moromisato, Satish Dhawan, G. Baum, F. Feinstein, T. Iwata, Yannis K. Semertzidis, J. Pyrlik, Mayda Velasco, L. Betev, S. Eichblatt, A. Witzmann, Patrick Hautle, P. Björkholm, T. Hasegawa, S. Dalla Torre, J. C. Faivre, L. Klostermann, J. M. Le Goff, F. Marie, J. S. McCarthy, C. Cavata, Regine Willumeit, Matias Rodriguez, C. Dulya, G. van Middelkoop, A. Ogawa, P. Berglund, B. Frois, S. Platchkov, Roy Weinstein, N. De Groot, J. Vogt, E. von Goeler, P. Shanahan, A. Kishi, A. Rosado, G. Rädel, G. Igo, S. Rock, T. Gaussiran, L. V. Kalinovskaya, Clemens A. Heusch, F. Simeoni, G.I. Smirnov, Ricardo Piegaia, T. Çuhadar, A. de Lesquen, J. Pretz, J. A. Garzon, Franco Bradamante, D. Y. Bardin, M. Giorgi, J. Polec, B. Badelek, C. Fernandez, R. Birsa, N. Hayashi, A. Sandacz, F. Perrot-Kunne, C.S. Ozben, S. Trentalange, D. G. Crabb, Yu. Kisselev, W. Wislicki, A. Steinmetz, T. Lindqvist, D. L. Adams, T. Akdogan, D. Pose, A. Rijllart, Bernardo Adeva, A. Dyring, Heinrich B. Stuhrmann, A. Staude, T. J. Ketel, V. W. Hughes, Ulrich Landgraf, A. Karev, F. Lehar, A. Magnon, A. Tripet, B. E. Bonner, M. Grosse-Perdekamp, Rudiger Voss, Michal Szleper, S. Ishimoto, R. van Dantzig, I. G. Bird, E. P. Sichtermann, K. Zaremba, M. Plo, U. Stiegler, Faustino Gómez, Kunikazu Mori, K. Medved, Anna Zanetti, K. Kurek, C. A. Whitten, Anne-Laure Martin, (Astro)-Particles Physics, D., Adam, B., Adeva, T., Akdogan, E., Arik, A., Arvidson, B., Badelek, M. K., Ballintijn, D., Bardin, G., Bardin, G., Baum, P., Berglund, L., Betev, I. G., Bird, Birsa, Renato, P., Björkholm, B. E., Bonner, N., de Botton, M., Boutemeur, Bradamante, Franco, A., Bravar, Bressan, Andrea, S., Bültmann, E., Burtin, C., Cavata, D., Crabb, J., Cranshaw, T., Çuhadar, DALLA TORRE, Silvia, R., van Dantzig, B., Derro, A., Deshpande, S., Dhawan, C., Dulya, A., Dyring, S., Eichblatt, J. C., Faivre, D., Fasching, F., Feinstein, C., Fernandez, B., Froi, A., Galla, J. A., Garzon, T., Gaussiran, Giorgi, Marcello, E., von Goeler, F., Gomez, G., Gracia, N., de Groot, M., Grosse Perdekamp, D., von Harrach, T., Hasegawa, P., Hautle, N., Hayashi, C. A., Heusch, N., Horikawa, V. W., Hughe, G., Igo, S., Ishimoto, T., Iwata, E. M., Kabuß, T., Kageya, L., Kalinovskaya, A., Karev, H. J., Kessler, T. J., Ketel, J., Kiryluk, A., Kishi, Kisselev, Y. u., L., Klostermann, D., Krämer, V., Krivokhijine, W., Kröger, V., Kukhtin, K., Kurek, J., Kyynäräinen, M., Lamanna, U., Landgraf, J. M., Le Goff, F., Lehar, A., de Lesquen, J., Lichtenstadt, T., Lindqvist, M., Litmaath, M., Lowe, A., Magnon, G. K., Mallot, F., Marie, Martin, Anna, J., Martino, T., Matsuda, B., Maye, J. S., Mccarthy, K., Medved, G., van Middelkoop, D., Miller, K., Mori, J., Moromisato, A., Nagaitsev, J., Nassalski, L., Naumann, T. O., Niinikoski, J. E. J., Oberski, A., Ogawa, C., Ozben, D. P., Park, F., Perrot Kunne, D., Peshekhonov, R., Piegaia, L., Pinsky, S., Platchkov, M., Plo, J., Polec, D., Pose, H., Postma, J., Pretz, R., Puntaferro, T., Pussieux, J., Pyrlik, G., Rädel, G., Rijllart, J. B., Robert, S., Rock, M., Rodriguez, E., Rondio, A., Rosado, I., Sabo, J., Saborido, A., Sandacz, I., Savin, Schiavon, Paolo, K. P., Schüler, R., Seitz, Y., Semertzidi, F., Sever, P., Shanahan, E. P., Sichtermann, Simeoni, Fabrizio, G. I., Smirnov, A., Staude, A., Steinmetz, U., Stiegler, H., Stuhrmann, M., Szleper, K. M., Teichert, F., Tessarotto, W., Tlaczala, S., Trentalange, A., Tripet, G., Unel, M., Velasco, J., Vogt, R., Vo, R., Weinstein, C., Whitten, R., Windmolder, R., Willumeit, W., Wislicki, A., Witzmann, A., Yañez, Y., Ylöstalo, Zanetti, ANNA MARIA, K., Zaremba, and J., Zhao

Subjects
Physics, DIS, Nuclear and High Energy Physics, Strange quark, Muon, SMC, Scattering, g1 structure function, Perturbative QCD, Deep inelastic scattering, Nuclear physics, High Energy Physics::Experiment, Sum rule in quantum mechanics, Nucleon, Particle Physics - Experiment, Spin-½
Abstract

We present a new measurement of the spin-dependent structure function $g_{1}^{\rm d}$ of the deuteron from deep inelastic scattering of 190 GeV polarized muons on polarized deuterons. The results are combined with our previous measurements of $g_{1}^{\rm d}$. A perturbative QCD evolution in next-to-leading order is used to compute $g_{1}^{\rm d}(x)$ at a constant $Q^{2}$. At $Q^{2} = 10$ GeV$^{2}$, we obtain a first moment $\Gamma_{1}^{\rm d} = \int_{0}^{1} g_{1}^{\rm d}{\rm d}x = 0.041 \pm 0.008$, a flavour-singlet axial charge of the nucleon $a_{0} = 0.30 \pm 0.08$, and an axial charge of the strange quark $a_{s} = -0.09 \pm 0.03$. Using our earlier determination of $\Gamma_{1}^{\rm p}$, we obtain $\Gamma_1^{\rm p} - \Gamma_1^{\rm n} = 0.183 \pm 0.035$ at $Q^2 = 10\,\mbox{GeV}^2$. This result is in agreement with the Bjorken sum rule which predicts $\Gamma_1^{\rm p} - \Gamma_1^{\rm n} = 0.186 \pm 0.002$ at the same $Q^2$.

Published
1997

39. Polarisation of valence and non-strange sea quarks in the nucleon from semi-inclusive spin asymmetries

Author

S. Lopez-Ponte, Yu. Kisselev, J. C. Faivre, T. O. Niinikoski, Alan D. Martin, Etienne Burtin, F. Marie, E. Rondio, T. Layda, P. Shanahan, M. Plo, K. M. Teichert, G.I. Smirnov, G. Bardin, Jinkui Zhao, R. E. Segel, A. Nagaitsev, J. M. Le Goff, K. P. Schüler, E. Arik, T. Kageya, Jay Roberts, Naoaki Horikawa, M. Grosse Perdekamp, J. H. Moromisato, S. K. Dhawan, D. Crabb, Cristino Pérez, M. Velasco, S. Dalla Torre, I. Sabo, Takahiro Iwata, J. Nassalski, J. Cranshaw, T. Gaussiran, D. J. Miller, S. Eichblatt, W. Wislicki, Iskender Atilla Reyhancan, V. G. Krivokhijine, T. Hasegawa, Michal Szleper, A. Steinmetz, Lawrence Pinsky, Patrick Hautle, J. Vogt, J.A. Garzon, J. S. McCarthy, J. Kyynäräinen, P. Schiavon, T. Matsuda, A. Ogawa, J. E.J. Oberski, S. Rock, I.G. Bird, Sergey M. Sergeev, A. Kishi, C. Fernandez, B. Frois, A. Rosado, M. Lowe, P. Björkholm, F. Sever, M. K. Ballintijn, C. Cavata, A. de Lesquen, H. J. Kessler, Abhay Deshpande, F. Feinstein, Roland Windmolders, E. P. Sichtermann, D. Peshekhonov, A. Arvidson, F. Tessarotto, L. Naumann, W. Kröger, I.A. Savin, V. W. Hughes, J. Martino, G. K. Mallot, Alessandro Bressan, C. Dulya, D. von Harrach, Roy Weinstein, N. De Groot, E. M. Kabuß, Clemens A. Heusch, Kunikazu Mori, R. Birsa, Yannis K. Semertzidis, B. W. Mayes, F. Lehar, J. Pyrlik, Ricardo Piegaia, K. Medved, E. Gülmez, R. Seitz, M. Giorgi, J. Pretz, D. Fasching, L. Betev, T. Pussieux, Aldo Penzo, G. Gracia, G. van Middelkoop, Ulrich Landgraf, N. de Botton, A. Sandacz, H. Postma, A. Witzmann, M. Lamanna, J. Saborido, L. Klostermann, Matias Rodriguez, B. Badelek, N. Hayashi, F. Perrot-Kunne, D. Pose, Regine Willumeit, A. Karev, G. Igo, A. Rijllart, A. Staude, T. Çuhadar, Bernardo Adeva, T. J. Ketel, Franco Bradamante, A. Dyring, Heinrich B. Stuhrmann, Anna Zanetti, C. A. Whitten, Günter Baum, P. Berglund, A. Magnon, E. von Goeler, A. Gomez, S. Platchkov, M. Litmaath, J. Lichtenstadt, D. Krämer, S. Ishimoto, U. Stiegler, R. van Dantzig, B. E. Bonner, C. S. Özben, Rudiger Voss, S. Bültmann, B., Adeva, E., Arik, A., Arvidson, B., Badelek, M. K., Ballintijn, G., Bardin, G., Baum, P., Berglund, L., Betev, I. G., Bird, R., Birsa, P., Björkholm, B. E., Bonner, N., de Botton, Bradamante, Franco, Bressan, Andrea, S., Bültmann, E., Burtin, C., Cavata, D., Crabb, J., Cranshaw, T., Çuhadar, DALLA TORRE, Silvia, R., van Dantzig, A., Deshpande, S., Dhawan, C., Dulya, A., Dyring, S., Eichblatt, J. C., Faivre, D., Fasching, F., Feinstein, C., Fernandez, B., Froi, J. A., Garzon, T., Gaussiran, Giorgi, Marcello, E., von Goeler, A., Gomez, G., Gracia, N., de Groot, M., Grosse Perdekamp, E., Gülmez, D., von Harrach, T., Hasegawa, P., Hautle, N., Hayashi, C. A., Heusch, N., Horikawa, V. W., Hughe, G., Igo, S., Ishimoto, T., Iwata, E. M., Kabuß, T., Kageya, A., Karev, H. J., Kessler, T. J., Ketel, A., Kishi, Kisselev, Y. u., L., Klostermann, D., Krämer, V., Krivokhijine, W., Kröger, J., Kyynäräinen, M., Lamanna, U., Landgraf, T., Layda, J. M., Le Goff, F., Lehar, A., de Lesquen, J., Lichtenstadt, M., Litmaath, S., Lopez Ponte, M., Lowe, A., Magnon, G. K., Mallot, F., Marie, Martin, Anna, J., Martino, T., Matsuda, B., Maye, J. S., Mccarthy, K., Medved, G., van Middelkoop, D., Miller, K., Mori, J., Moromisato, A., Nagaitsev, J., Nassalski, L., Naumann, T. O., Niinikoski, J. E. J., Oberski, A., Ogawa, C., Ozben, A., Penzo, C., Perez, F., Perrot Kunne, D., Peshekhonov, R., Piegaia, L., Pinsky, S., Platchkov, M., Plo, D., Pose, H., Postma, J., Pretz, T., Pussieux, J., Pyrlik, I., Reyhancan, A., Rijllart, J. B., Robert, S., Rock, M., Rodriguez, E., Rondio, A., Rosado, I., Sabo, J., Saborido, A., Sandacz, I., Savin, Schiavon, Paolo, K. P., Schüler, R., Segel, R., Seitz, Y., Semertzidi, S., Sergeev, F., Sever, P., Shanahan, E. P., Sichtermann, G. I., Smirnov, A., Staude, A., Steinmetz, U., Stiegler, H., Stuhrmann, M., Szleper, K. M., Teichert, F., Tessarotto, M., Velasco, J., Vogt, R., Vo, R., Weinstein, C., Whitten, R., Windmolder, R., Willumeit, W., Wislicki, A., Witzmann, Zanetti, ANNA MARIA, J., Zhao, and (Astro)-Particles Physics

Subjects
Physics, Quark, Nuclear and High Energy Physics, Particle physics, Muon, Valence (chemistry), spin dependent parton distribution, High Energy Physics::Phenomenology, Hadron, Nuclear Theory, Deep inelastic scattering, valence quarks, Nuclear physics, Distribution function, spin dependent parton distributions, Deuterium, deep inelastic scattering, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Nucleon, Particle Physics - Experiment
Abstract

We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range 0.003

Published
1996

40. Recent results of the study of hadronic production with the CMD-2 and SND detectors at the VEPP-2M collider

Author

S. I. Serednyakov, N.M. Ryskulov, A. I. Milstein, A.V. Vasiljev, K. Y. Mikhailov, D.N. Grigoriev, A.S. Zaitsev, V.A. Sidorov, D.V. Bondarev, Z. K. Silagadze, Fedor Ignatov, S.E. Baru, E.V. Pakhtusova, I.B. Logashenko, A.E. Bondar, A.L. Sibidanov, Yu.V. Yudin, S.V. Karpov, Alexander Valishev, P. Krokovny, A.N. Skrinsky, A.V. Berdugin, A. Baratt, A.S. Kuzmin, Yuri Shatunov, A.S. Popov, Konstantin Beloborodov, P.A. Lukin, D.A. Bukin, A.V. Otboev, I. A. Koop, D. Epifanov, V.M. Aulchenko, A.A. Ruban, B.A. Shwartz, A. A. Korol, Alexander Bogdanchikov, N.I. Root, T.V. Dimova, S.I. Redin, E.A. Perevedentsev, V.S. Okhapkin, S.V. Koshuba, B.I. Khazin, V. W. Hughes, S.G. Zverev, M. N. Achasov, J. A. Thompson, R.R. Akhmetshin, V. P. Druzhinin, L.M. Barkov, N. Gabyshev, A.A. Polunin, E. P. Solodov, A. P. Lysenko, D.A. Gorbachev, N.S. Bashtovoy, A.A. Grebeniuk, Yu. V. Usov, A.G. Shamov, Vassili Kazanin, A. V. Bozhenok, Igor Nesterenko, G.V. Fedotovitch, I.G. Snopkov, S.I. Eidelman, A. D. Bukin, A.V. Bragin, and V.Sh. Banzarov

Subjects
Physics, Luminosity (scattering theory), Annihilation, Physics and Astronomy (miscellaneous), Meson, Physics::Instrumentation and Detectors, Hadron, Elementary particle, law.invention, Nuclear physics, Particle decay, law, High Energy Physics::Experiment, Vector meson, Collider, Engineering (miscellaneous)
Abstract

The Cryogenic Magnetic Detector (CMD-2) and Spherical Neutral Detector (SND) operated at the VEPP-2M electron-positron collider in the c.m. energy range 360-1380 MeV. The total integrated luminosity above 60 pb–1 has been collected by both detectors. The cross sections of hadronic production have been measured with high precision. New results for the light vector meson parameters and rare decay mode were obtained. PACS: 13.66.Bc Hadron production in e – e + interactions – 13.66.Jn Precision measurements in e – e + interactions

Published
2004

41. Measurement of φ meson parameters with CMD-2 detector at VEPP-2M collider

Author

I.G. Snopkov, V.V Danilov, B.A. Shwartz, A.A. Grebeniuk, W. A. Worstell, A.A Ruban, Igor Nesterenko, V.G Zavarzin, G.V. Fedotovich, C.M Valine, D.H Brown, M.A Shubin, B.L. Roberts, B.O Baibusinov, V.M. Titov, I.B. Logashenko, N. Gabyshev, V.M Aulchenko, E. P. Solodov, V. W. Hughes, A.V Maksimov, Yu.I Merzlyakov, B.I. Khazin, A.I. Sukhanov, N.M. Ryskulov, S.E Baru, A.N. Skrinsky, S. K. Dhawan, R.R. Akhmetshin, G.A Aksenov, V. S. Banzarov, P. Cushman, J. A. Thompson, D.N. Grigoriev, T. A. Purlats, V.S. Okhapkin, S.I. Eidelman, J. P. Miller, V.A. Sidorov, A.A Polumin, A.E Sher, V.I Ptitzyn, I. A. Koop, P.M. Ivanov, Yu. M. Shatunov, A.P. Lysenko, E.V Popkov, Yu.V. Yudin, A.S. Kuzmin, N.I Root, E.A. Perevedentsev, S.I. Redin, V.P. Smakhtin, A. Bondar, L.M. Barkov, V.A Monitch, and E.V Anashkin

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, Physics::Instrumentation and Detectors, Hadron, Detector, law.invention, Nuclear physics, General purpose, law, Physics::Accelerator Physics, High Energy Physics::Experiment, Collider
Abstract

Results of the measurement of the φ meson parameters with the general purpose detector CMD-2 at the upgraded e + e − collider VEPP-2M at Novosibirsk are presented. This is the first measurement of the four major φ decay modes in a single e + e − experiment. The results based on about 55,600 identified hadronic events are consistent with previous measurements, and have precision comparable to the current world average.

Published
1995

42. Observation of resonance line narrowing for old muonium

Author

X. Fei, Wen Liu, V. W. Hughes, X. Wang, Satish Dhawan, M. G. Boshier, Q. Xu, R. Prigl, Klaus-Peter Jungmann, W. Schwarz, K. A. Woodle, Paul Souder, G. zu Putlitz, O. B. van Dyck, C. Pillai, I. Reinhard, and Markus Janousch

Subjects
Physics, symbols.namesake, Zeeman effect, Condensed matter physics, Muonium, symbols, Resonance, Atomic physics, Hyperfine structure, Resonance line, Atomic and Molecular Physics, and Optics, Magnetic field, Line (formation)
Abstract

Resonance line narrowing up to 1/2 of the natural linewidth has been observed for microwave magnetic-resonance transitions between Zeeman levels of ground-state muonium at a strong magnetic field of 1.7 T. The observed lines are in good agreement with predicted line shapes and are useful for a precision determination of \ensuremath{\Delta}\ensuremath{\nu} and ${\mathrm{\ensuremath{\mu}}}_{\mathrm{\ensuremath{\mu}}}$/${\mathrm{\ensuremath{\mu}}}_{\mathit{p}}$.

Published
1995

43. Extraction of the RatioF2n/F2pfrom Muon-Deuteron and Muon-Proton Scattering at SmallxandQ2

Author

Andris Skuja, G. Siegert, R. Davisson, G. Y. Fang, V. Eckardt, H. E. Montgomery, F. M. Pipkin, A. Banerjee, A. Salvarani, D. G. Michael, W. Dougherty, P. Spentzouris, Henry Lubatti, G. A. Snow, M. Wilhelm, R. S. Guo, S. Aïd, T. Dreyer, V. Papavassiliou, D. McLeod, S. O'Day, K. A. Griffioen, Jan Figiel, H. E. Jackson, K. P. Schüler, E. J. Ramberg, S. Magill, M. D. Baker, B. Baller, H. J. Gebauer, J. J. Ryan, I. Derado, J. Haas, W. Wittek, L.S. Osborne, M. R. Adams, D. Hantke, M. Erdmann, Z. Jin, A. Manz, D. E. Jaffe, A. Zghiche, Roger W. Finlay, H. G. E. Kobrak, R. A. Swanson, H. Schellman, G. Jancso, K. Olkiewicz, A. Röser, Richard Wilson, K. Hicks, H. L. Melanson, P. L. Anthony, S. Söldner-Rembold, Shuichi Kunori, U. Bratzler, H. E. Stier, R. B. Nickerson, N. Schmitz, P. Madden, H. L. Clark, Tiefu Zhao, Michael Schmitt, B. Pawlik, D. H. Potterveld, D. M. Jansen, A. V. Kotwal, R. D. Kennedy, U. Ecker, E. R. Kinney, J. J. Lord, R. Otten, S. B. Kaufman, D. A. Averill, S. Wolbers, H. M. Braun, P. Stopa, Satish Dhawan, C. Halliwell, D. F. Geesaman, V. W. Hughes, C. W. Salgado, Janet Conrad, Timothy J. Carroll, Jorge G. Morfin, J. Novak, H. Venkataramania, F. S. Dietrich, and A. A. Bhatti

Subjects
Nuclear physics, Physics, Muon, Deuterium, Proton, Scattering, Proton scattering, Structure function, Analytical chemistry, General Physics and Astronomy
Abstract

The ratio of the deuteron to proton structure functions is measured at very small Bjorken {ital x} (down to 10{sup --6}) and for {ital Q}{sup 2}{gt}0.001 GeV{sup 2} from scattering of 470 GeV muons on liquid hydrogen and deuterium targets. The ratio {ital F}{sup {ital n}}{sub 2}/{ital F}{sup {ital p}}{sub 2} extracted from these measurements is found to be constant, at a value of 0.935{plus_minus}0.008{plus_minus}0.034, for {ital x}{lt}0.01. This result suggests the presence of nuclear shadowing effects in the deuteron. The dependence of the ratio on {ital Q}{sup 2} is also examined; no significant variation is found.

Published
1995

44. Measurement of Nuclear Transparencies from Exclusiveρ0Meson Production in Muon-Nucleus Scattering at 470 GeV

Author

S. Lancaster, R. A. Swanson, H. Schellman, M. Wilhelm, M. Erdmann, R. S. Guo, K. P. Schüler, G. A. Snow, R. D. Kennedy, T. Kirk, A. Banerjee, V. Papavassiliou, W. Wittek, Shuichi Kunori, A. A. Bhatti, H. E. Stier, S. Aïd, Janet Conrad, Timothy J. Carroll, B. Pawlik, Roger W. Finlay, Satish Dhawan, D. F. Geesaman, C. Halliwell, F. M. Pipkin, K. Hicks, Richard Wilson, H. G. E. Kobrak, F. Faller, U. Bratzler, V. W. Hughes, T. Zhao, D. McLeod, C. W. Salgado, D. G. Michael, H. L. Melanson, P. Spentzouris, A. Salvarani, N. Schmitz, Michael Schmitt, D. H. Potterveld, S. Wolbers, E. R. Kinney, J. J. Lord, B. Baller, S. Magill, J. J. Ryan, Andris Skuja, A. Röser, H. Venkataramania, F. S. Dietrich, Z. Jin, Jorge G. Morfin, D. A. Averill, A. V. Kotwal, R. Davisson, S. O'Day, W. Dougherty, V. Eckardt, H. E. Montgomery, K. A. Griffioen, H. E. Jackson, H. J. Gebauer, G. Y. Fang, I. Derado, H. M. Braun, P. Stopa, A. Manz, S. Söldner-Rembold, M. D. Baker, D. Hantke, G. Siegert, Wit Busza, H. Breidung, R. Otten, S. B. Kaufman, T. Dreyer, L.S. Osborne, M. R. Adams, E. J. Ramberg, J. Haas, P. Madden, H. L. Clark, D. M. Jansen, Henry Lubatti, A. Zghiche, G. Jancso, P. L. Anthony, R. B. Nickerson, K. Olkiewicz, Jan Figiel, and U. Ecker

Subjects
Physics, Nuclear reaction, Particle physics, Muon, Meson, Physics::Instrumentation and Detectors, Scattering, Nuclear Theory, Tevatron, General Physics and Astronomy, Nuclear physics, Deuterium, Nuclear transparency, Physics::Accelerator Physics, High Energy Physics::Experiment, Fermilab, Nuclear Experiment
Abstract

Nuclear transparencies measured in exclusive incoherent ${\mathrm{\ensuremath{\rho}}}^{0}$ meson production from hydrogen, deuterium, carbon, calcium, and lead in muon-nucleus scattering are reported. The data were obtained with the E665 spectrometer using the Fermilab Tevatron muon beam with a mean beam energy of 470 GeV. Increases in the nuclear transparencies are observed as the virtuality of the photon increases, in qualitative agreement with the expectations of color transparency.

Published
1995

45. Scaled energy (z) distributions of charged hadrons observed in deep-inelastic muon scattering at 490 GeV from xenon and deuterium targets

Author

S. Magill, A. Eskreys, W. Wittek, B. Pawlik, R. A. Swanson, P. H. Steinberg, H. Venkataramania, H. Schellman, M. Wilhelm, S. Wolbers, H. G. E. Kobrak, H. M. Braun, U. Ecker, P. Malecki, Ronald Gilman, W. Dougherty, M. D. Baker, S. Krzywdzinski, S. Aïd, R. L. Talaga, Satish Dhawan, C. Halliwell, D. Hantke, N. Schmitz, Shuichi Kunori, G. A. Snow, J. Wilkes, A. Salvarani, D. G. Michael, Jim Hanlon, D. F. Geesaman, S. Söldner-Rembold, R. Davisson, Jorge G. Morfin, H. E. Jackson, T. Kirk, V. Papavassiliou, K. Dziunikowska, F. M. Pipkin, M. C. Green, A. A. Bhatti, H. L. Melanson, V. W. Hughes, H. J. Trost, Richard Wilson, G. Coutrakon, A. Manz, S. O'Day, Wit Busza, Janet Conrad, H. J. Seyerlein, Timothy J. Carroll, H. E. Stier, Andris Skuja, J. F. Bartlett, I. Derado, W. Mohr, Michael Schmitt, S. Tentindo-Repond, A. Röser, V. Eckardt, H. E. Montgomery, H. J. Gebauer, D. McLeod, T. Dreyer, L.S. Osborne, M. Vidal, M. R. Adams, J. J. Ryan, J. Haas, P.L. Anthony, Tiefu Zhao, E. J. Ramberg, Martin Erdmann, S. B. Kaufman, D. M. Jansen, D. E. Jaffe, K. P. Schüler, P. Stopa, R. D. Kennedy, Henry Lubatti, G. Jancso, J. J. Lord, K. Olkiewicz, R. B. Nickerson, and Jan Figiel

Subjects
Physics, Nuclear reaction, Particle physics, Muon, Scattering, Computer Science::Information Retrieval, Momentum transfer, Hadron, Inelastic scattering, Deep inelastic scattering, Nuclear physics, Deuterium, High Energy Physics::Experiment, Nuclear Experiment
Abstract

Fermilab Experiment-665 measured deep-inelastic scattering of 490 GeV muons off deuterium and xenon targets. Events were selected with a range of energy exchange [nu] from 100 GeV to 500 GeV and with large ranges of [ital Q][sup 2] and [ital x][sub Bj]: 0.1 GeV[sup 2]/[ital c][sup 2][lt][ital Q][sup 2][lt]150 GeV[sup 2]/[ital c][sup 2] and 0.001[lt][ital x][sub Bj][lt]0.5. The fractional energy ([ital z]) distributions of forward-produced hadrons from the two targets have been compared as a function of the kinematics of the scattering; specifically, the kinematic region of shadowing'' has been compared to that of nonshadowing. The dependence of the distributions upon the [ital order] of the hadrons, determined by the fractional energies, has been examined as well; a strong degree of similarity has been observed in the shapes of the distributions of the different order hadrons. These [ital z] distributions, however, show no nuclear dependence, even in the kinematic region of shadowing.

Published
1994

46. A measurement of the 1S–2S transition frequency in muonium

Author

W. Schwarz, H. Geerds, J.R.M. Barr, M.A. Persaud, G. H. Eaton, I. Reinhard, L. Zhang, Klaus-Peter Jungmann, Pavel Matousek, Lorenz Willmann, B. Braun, V. W. Hughes, Michael Towrie, G. Woodman, G. zu Putlitz, Erling Riis, Allister I. Ferguson, M. G. Boshier, W.T. Toner, K. Woodle, Björn Matthias, D. Berkeland, P E G Baird, F. Maas, and P.G.H. Sandars

Subjects
Physics, Rydberg constant, Muon, Deuterium, Atom, Muonium, General Physics and Astronomy, Atomic physics, Spectroscopy, Hyperfine structure, Lamb shift
Abstract

Doppler-free two-photon laser spectroscopy has been employed to measure the 1 2 S 1 2 −2 2 S 1 2 transition in the muonium atom (μ+e−). A value of 2 455 529 002(33) (46) MHz has been obtained, which agrees with QED calculations within two standard deviations. The Lamb shift contributions are tested to the level 8×10−3. The corresponding measurements in hydrogen and deuterium using the same apparatus and laser system provide a test of the applied systematic corrections and have verified the systematic error of 46 MHz quoted. The mass of the positive muon has been derived from the isotope shift in this transition and yields a value of 105.65880(29)(43) MeV c 2 .

Published
1994

47. Measurement of the polarisation of a high energy muon beam

Author

Shafqat Ahmad, E. Burtin, B. Frois, M. Grosse Perdekamp, R. Seitz, S. Dhawan, Drew Parks, I. Savin, M. Litmaath, M. D. Corcoran, B. Adeva, R.E. Segel, Alan D. Martin, John C. Mitchell, K. P. Schüler, J. Cranshaw, Günter Baum, T. Pussieux, Per Berglund, A. Rijllart, H. J. Kessler, Alessandro Bressan, M. Plo, G. Perez, D. von Harrach, T. Gaussiran, Roland Windmolders, Naoaki Horikawa, B. E. Bonner, M. Rodriguez, A. Arvidson, Kwong Lau, F. Marie, J. Pyrlik, C. A. Whitten, J. C. Faivre, Gerhard K. Mallot, W. Tlaczala, E. von Goeler, M. Clocchiatti, F. Lehar, D. Sanders, I. Sabo, D. Fasching, G. Igo, J.A. Buchanan, J. M. Rieubland, M. K. Ballintijn, David Miller, T. Lindqvist, Rudiger Voss, J. H. Moromisato, A. Rosado, S. Trentalange, S. Bültmann, Aldo Penzo, J. A. Garzon, Shoji Okumi, R. Kaiser, G. Bardin, A. Witzmann, Franco Bradamante, J. E.J. Oberski, S. Ishimoto, J. Martino, A. Dyring, G. van Middelkoop, V. G. Krivokhijine, J. Nassalski, B. Badelek, Sergey M. Sergeev, W. Thiel, A. Brüll, Yu. Kisselev, J. Dupont, U. Landgrat, C. Fernandez, A. Karev, G. Gracia, F. Feinstein, A. Sandacz, N. Hayashi, P. Schiavon, S. Dalla Torre, M. Velasco, R. van Dantzig, F. Perrot-Kunne, Wojciech Wislicki, S. Eichblatt, T. Hasegawa, Anna Zanetti, M. Boutemeur, G.S. Mutchler, L. Ropelewski, S. Lopez-Ponte, A. de Lesquen, H. Stuhrmann, C. A. Heusch, C. Dulya, Andrés Gómez, I. G. Bird, L. Klostermann, T. Çuhadar, A. Kishi, Ricardo Piegaia, M. Giorgi, J. Lichtenstadt, K. M. Teichert, M. de Jong, E. Rondio, T. Layda, A. Staude, J. Kyynäräinen, Jay Roberts, D. Pose, Y. Tzamouranis, J. M. Demolis, Lawrence Pinsky, Donald Crabb, Tjeerd Ketel, V. W. Hughes, Takahiro Iwata, J. S. McCarthy, P. Björkholm, F. Tessarotto, C. Cavata, S. Platchkov, P. Shanahan, Kunikazu Mori, L. Naumann, Roy Weinstein, G. Smirnov, L. Betev, K. Zaremba, E. M. Kabuss, C. Garabatos, R. Birsa, A. Magnon, J.M. Clement, B. W. Mayes, J. Saborido, J. Vogt, N. de Botton, Victor Kukhtin, M. Lamanna, D.V. Peshekhonov, M. Lowe, J. P. Chen, L. Gatignon, Donal Day, Jinkui Zhao, Aina Yañez, F. Sever, T. O. Niinikoski, H. Postma, A. Steinmetz, B., Adeva, S., Ahmad, A., Arvidson, B., Badelek, M. K., Ballintijn, G., Bardin, G., Baum, P., Berglund, L., Betev, I. G., Bird, Birsa, Renato, P., Björkholm, B. E., Bonner, N., de Botton, M., Boutemeur, Bradamante, Franco, Bressan, Andrea, A., Brüll, J., Buchanan, S., Bültmann, E., Burtin, C., Cavata, J. P., Chen, J., Clement, M., Clocchiatti, M. D., Corcoran, D., Crabb, J., Cranshaw, T., Çuhadar, DALLA TORRE, Silvia, R., van Dantzig, D., Day, J. M., Demoli, S., Dhawan, C., Dulya, J., Dupont, A., Dyring, S., Eichblatt, J. C., Faivre, D., Fasching, F., Feinstein, C., Fernandez, B., Froi, C., Garabato, J. A., Garzon, L., Gatignon, T., Gaussiran, Giorgi, Marcello, E., von Goeler, A., Gomez, G., Gracia, M., Grosse Perdekamp, D., von Harrach, T., Hasegawa, N., Hayashi, C. A., Heusch, N., Horikawa, V. W., Hughe, G., Igo, S., Ishimoto, T., Iwata, M., de Jong, E. M., Kabu, R., Kaiser, A., Karev, H. J., Kessler, T. J., Ketel, A., Kishi, Kisselev, Y. u., L., Klostermann, V., Krivokhijine, V., Kukhtin, J., Kyynäräinen, M., Lamanna, U., Landgrat, K., Lau, T., Layda, F., Lehar, A., de Lesquen, J., Lichtenstadt, T., Lindqvist, M., Litmaath, S., Lopez Ponte, M., Lowe, A., Magnon, G. K., Mallot, F., Marie, Martin, Anna, J., Martino, B., Maye, J. S., Mccarthy, G., van Middelkoop, D., Miller, J., Mitchell, K., Mori, J., Moromisato, G. S., Mutchler, J., Nassalski, L., Naumann, T. O., Niinikoski, J. E. J., Oberski, S., Okumi, D. P., Park, A., Penzo, G., Perez, F., Perrot Kunne, D., Peshekhonov, R., Piegaia, L., Pinsky, S., Platchkov, M., Plo, D., Pose, H., Postma, T., Pussieux, J., Pyrlik, J. M., Rieubland, A., Rijllart, J. B., Robert, M., Rodriguez, E., Rondio, L., Ropelewski, A., Rosado, I., Sabo, J., Saborido, A., Sandacz, D., Sander, I., Savin, Schiavon, Paolo, K. P., Schüler, R., Segel, R., Seitz, S., Sergeev, F., Sever, P., Shanahan, G., Smirnov, A., Staude, A., Steinmetz, H., Stuhrmann, W., Tlaczala, K. M., Teichert, F., Tessarotto, W., Thiel, S., Trentalange, Y., Tzamourani, M., Velasco, J., Vogt, R., Vo, R., Weinstein, C., Whitten, R., Windmolder, W., Wislicki, A., Witzmann, A., Yañez, Zanetti, ANNA MARIA, K., Zaremba, and J., Zhao

Subjects
Physics, Nuclear and High Energy Physics, Large Hadron Collider, Muon, Physics::Instrumentation and Detectors, Polarimeter, positron energy spectrum, muon beam polarimeter, Nuclear physics, Positron, Energy spectrum, Physics::Accelerator Physics, High Energy Physics::Experiment, Detectors and Experimental Techniques, Nuclear Experiment, Instrumentation, Energy (signal processing), Beam (structure)
Abstract

A muon beam polarimeter has been built for the SMC experiment at the CERN SPS, for muon energies of 100 to 200 GeV. The beam polarisation is determined from the energy spectrum of positrons from the decay μ+ → e+ νcνμ. A polarisation of - 0.82 is measured with a relative systematic accuracy of 3%.

Published
1994

48. Q2dependence of the average squared transverse energy of jets in deep-inelastic muon-nucleon scattering with comparison to perturbative QCD predictions

Author

W. Wittek, H. Venkataramania, H. G. E. Kobrak, Jim Hanlon, G. A. Snow, S. Krzywdzinski, D. M. Jansen, S. Söldner-Rembold, Shuichi Kunori, Henry Lubatti, S. Arndotïd, B. Pawlik, D. F. Geesaman, Satish Dhawan, C. Halliwell, D. G. Michael, S. Wolbers, G. Coutrakon, Jorge G. Morfin, Jan Figiel, H. L. Melanson, V. W. Hughes, J. Wilkes, U. Ecker, P. Malecki, M. D. Baker, F. M. Pipkin, E. J. Ramberg, Martin Erdmann, H. M. Braun, H. J. Gebauer, W. Dougherty, A. Manz, V. Papavassiliou, L.S. Osborne, C. W. Salgado, H. E. Jackson, Andris Skuja, M. R. Adams, T. Kirk, H. E. Stier, D. Hantke, R. B. Nickerson, K. Dziunikowska, Ronald Gilman, D. E. Jaffe, V. Eckardt, S. O'Day, G. Jancso, N. Schmitz, H. E. Montgomery, A. Eskreys, M. Wilhelm, R. Davisson, R. A. Swanson, P. H. Steinberg, H. Schellman, R. L. Talaga, J. J. Ryan, S. Magill, M. C. Green, D. McLeod, K. Olkiewicz, Michael Schmitt, S. Tentindo-Repond, A. Salvarani, H. J. Trost, A. A. Bhatti, Janet Conrad, T. Dreyer, J. F. Bartlett, K. P. Schüler, A. Röser, I. Derado, J. J. Lord, W. Mohr, J. Haas, P.L. Anthony, Wit Busza, Tiefu Zhao, Richard Wilson, S. B. Kaufman, P. Stopa, and R. D. Kennedy

Subjects
Physics, Quantum chromodynamics, Particle physics, Muon, Computer Science::Information Retrieval, Momentum transfer, General Physics and Astronomy, Perturbative QCD, Parton, Inelastic scattering, Deep inelastic scattering, Nuclear physics, High Energy Physics::Experiment, Nuclear Experiment, Nucleon
Abstract

The average squared transverse energy of jets in deep-inelastic muon-nucleon scattering is measured as a function of the momentum transfer squared ([ital Q][sup 2]), in the range 3[lt][ital Q][sup 2][lt]25 GeV[sup 2]. Perturbative QCD predicts that the average squared parton transverse energy will depend upon the strong coupling constant ([alpha][sub [ital S]]). Identifying the transverse energy of the jets with those of the corresponding partons, [alpha][sub [ital S]] is found to vary with [ital Q][sup 2] as predicted by QCD.

Published
1994

49. Perturbative QCD effects observed in 490 GeV deep-inelastic muon scattering

Author

K. P. Schüler, S. Aïd, Norbert Schmitz, D. F. Geesaman, U. Ecker, M. Erdmann, Mark Raymond Adams, K. Olkiewicz, K. Dziunikowska, R. L. Talaga, T. Kirk, P. L. Anthony, Pa. Malecki, Wit Busza, M. D. Baker, Ronald Gilman, H. J. Trost, B. Pawlik, S. Krzywdzinski, H. J. Gebauer, H. L. Melanson, A. Eskreys, S. O'Day, D. McLeod, Shuichi Kunori, R. A. Swanson, P. H. Steinberg, H. Schellman, Jan Figiel, R. Davisson, J. J. Lord, H. E. Stier, Jorge G. Morfin, D. G. Michael, F. M. Pipkin, E. J. Ramberg, S. Wolbers, S. Magill, R. D. Kennedy, V. Papavassiliou, D. E. Jaffe, R. B. Nickerson, W. Dougherty, D. M. Jansen, Michael Schmitt, C. Halliwell, L. S. Osborne, V. W. Hughes, C. W. Salgado, J. Wilkes, S. K. Dhawan, A. Röser, Richard Wilson, H. Venkataramania, A. A. Bhatti, A. Manz, A. Salvarani, D. Hantke, Andris Skuja, V. Eckardt, G. A. Snow, H. E. Montgomery, Janet Conrad, G. Coutrakon, J. J. Ryan, T. Dreyer, J. Haas, H. M. Braun, P. Stopa, S. Söldner-Rembold, Tiefu Zhao, M. C. Green, S. B. Kaufman, H. E. Jackson, W. Wittek, H. G. E. Kobrak, J. F. Bartlett, G. Jancso, I. Derado, S. Tentindo-Repond, W. Mohr, Jim Hanlon, Henry Lubatti, and M. Wilhelm

Subjects
Quantum chromodynamics, Physics, Particle physics, Muon, Computer Science::Information Retrieval, High Energy Physics::Phenomenology, Hadron, Perturbative QCD, Elementary particle, Parton, Inelastic scattering, Deep inelastic scattering, Nuclear physics, High Energy Physics::Experiment, Nuclear Experiment
Abstract

Results on forward charged hadrons in 490 GeV deep-inelastic muon scattering are presented. The transverse momenta, azimuthal asymmetry, and energy flow of events with four or more forward charged hadrons are studied. The range of the invariant hadronic mass squared 300[lt][ital W][sup 2][lt]900 GeV[sup 2]/[ital c][sup 4] extends higher than previous deep-inelastic muon scattering experiments. Data are compared to the predictions of the Lund Monte Carlo model with perturbative QCD simulated by matrix elements, parton showers, and color dipole radiation. All of the QCD-based models are consistent with the data while a model without QCD processes is not. Correlations with the multiplicity-independent event variable [Pi][congruent][summation][vert bar][ital p][sub [ital T]][vert bar] are studied. The relationship between the azimuthal asymmetry and transverse momentum of forward hadrons is also presented. The data are most consistent with intrinsic parton transverse momentum squared [ital k][sub [ital T]][sup 2] of 0.25 GeV[sup 2]/[ital c][sup 2].

Published
1993

50. A chopped high intensity muon beam at the Stopped Muon Channel at LAMPF

Author

X. Fei, K. Woodle, Björn Matthias, C. Pillai, H. E. Ahn, V. W. Hughes, R. Dixson, and D. Ciskowski

Subjects
Physics, Nuclear and High Energy Physics, Muon, Extinction ratio, Physics::Instrumentation and Detectors, Muonium, Resonance, Chopper, Momentum, Nuclear physics, Physics::Accelerator Physics, High Energy Physics::Experiment, Instrumentation, Beam (structure), Voltage
Abstract

A chopped positive muon beam with high intensity, low momentum, and high purity has been developed at LAMPF using a high voltage chopper system. The rise and fall times of the chopped muon beam are approximately 100 ns, the repetition rate extends up to 100 kHz and the extinction ratio for muons is 0.3%. The beam chopper system is described and the test results are presented. This chopped high intensity μ + beam is to be used to achieve resonance line-narrowing in a precision microwave spectroscopy experiment on muonium.

Published
1993

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