Search Results - (Author, Cooperation:K. Ragan)

Showing 1 - 10 results of 10, query time: 0.17s Refine Results
  1. 1
    E. Aliu ; T. Arlen ; T. Aune ; M. Beilicke ; W. Benbow ; A. Bouvier ; S. M. Bradbury ; J. H. Buckley ; V. Bugaev ; K. Byrum ; A. Cannon ; A. Cesarini ; J. L. Christiansen ; L. Ciupik ; E. Collins-Hughes ; M. P. Connolly ; W. Cui ; R. Dickherber ; C. Duke ; M. Errando ; A. Falcone ; J. P. Finley ; G. Finnegan ; L. Fortson ; A. Furniss ; N. Galante ; D. Gall ; K. Gibbs ; G. H. Gillanders ; S. Godambe ; S. Griffin ; J. Grube ; R. Guenette ; G. Gyuk ; D. Hanna ; J. Holder ; H. Huan ; G. Hughes ; C. M. Hui ; T. B. Humensky ; A. Imran ; P. Kaaret ; N. Karlsson ; M. Kertzman ; D. Kieda ; H. Krawczynski ; F. Krennrich ; M. J. Lang ; M. Lyutikov ; A. S. Madhavan ; G. Maier ; P. Majumdar ; S. McArthur ; A. McCann ; M. McCutcheon ; P. Moriarty ; R. Mukherjee ; P. Nunez ; R. A. Ong ; M. Orr ; A. N. Otte ; N. Park ; J. S. Perkins ; F. Pizlo ; M. Pohl ; H. Prokoph ; J. Quinn ; K. Ragan ; L. C. Reyes ; P. T. Reynolds ; E. Roache ; H. J. Rose ; J. Ruppel ; D. B. Saxon ; M. Schroedter ; G. H. Sembroski ; G. D. Senturk ; A. W. Smith ; D. Staszak ; G. Tesic ; M. Theiling ; S. Thibadeau ; K. Tsurusaki ; J. Tyler ; A. Varlotta ; V. V. Vassiliev ; S. Vincent ; M. Vivier ; S. P. Wakely ; J. E. Ward ; T. C. Weekes ; A. Weinstein ; T. Weisgarber ; D. A. Williams ; B. Zitzer
    American Association for the Advancement of Science (AAAS)
    Published 2011
    Staff View
    Publication Date:
    2011-10-08
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  2. 2
    Staff View
    ISSN:
    1434-6052
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract In an experiment at the CERN-SPS charged hyperon beam, we have investigated the inclusive $$\Lambda \bar K^0 $$ and $$\Sigma ^0 \bar K^0 $$ final states formed in Ξ− Be interactions. In the $$\Lambda \bar K^0 $$ channel, we observe a signal at 1826 MeV/c2 which can be identified with the known Ξ(1820) resonance. We determine its mass and width to be:M=1826±4 MeV/c2, Г=12±14 MeV/c2. A moment analysis is consistent with a spin of 3/2 and indicates a negative parity for this spin assignment. Also in the $$\Lambda \bar K^0 $$ channel, we observe a 3.6σ signal with the following parameters:M=1963±5 MeV/c2, Г=25±15 MeV/c2. This state, which we call Ξ(1960), is not observed in the $$\Sigma ^0 \bar K^0 $$ channel, leading to an upper limit on the ratio of partial widths $$\Sigma \bar K/\Lambda \bar K$$ of 2.3 (90% confidence level). A moment analysis of the $$\Lambda \bar K^0 $$ final state indicates a spin of 5/2 or greater in the natural spin-parity series 5/2+, 7/2−, etc.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  3. 3
    Staff View
    ISSN:
    1434-6052
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract The cross sections for Ξ− and Ω− inclusive production in Ξ− Be collisions at 116 GeV/c have been measured in the kinematic domain [0.1〈x F 〈0.9, 0〈p T 〈1.7 GeV/c]. The integrated cross sections per nucleon are found to be about twice as large as in Ξ− p collisions. The invariant cross sections increase by a factor of 70 for the Ξ− s and of 100 for the Ω− s between the central region (x F ∼0.2) and the projectile fragmentation region (x F ∼0.8). In the central region, they have about the same magnitude as the ones for Ξ− and Ω− inclusive production inp nucleon collisions. The Ξ− and Ω− polarisations have been measured over the same kinematic domain and are found to be compatible with zero.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  4. 4
    Staff View
    ISSN:
    0168-9002
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Physics
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  5. 5
    Staff View
    ISSN:
    0168-9002
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Physics
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  6. 6
    Staff View
    ISSN:
    1434-6052
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract In an experiment performed in the CERN SPS hyperon beam we have obtained a value for the branching ratio $${{\Sigma ^ + \to p\gamma } \mathord{\left/ {\vphantom {{\Sigma ^ + \to p\gamma } {\Sigma ^ + \to p\pi }}} \right. \kern-\nulldelimiterspace} {\Sigma ^ + \to p\pi }}^0 of\left( {2.46_{ - 0.35}^{ + 0.30} } \right) \times 10^{ - 3} ,$$ corresponding to a branching ratio $${{\Sigma ^ + \to p\gamma } \mathord{\left/ {\vphantom {{\Sigma ^ + \to p\gamma } {\Sigma ^ + \to all}}} \right. \kern-\nulldelimiterspace} {\Sigma ^ + \to all}}of\left( {1.27_{ - 0.18}^{ + 0.16} } \right) \times 10^{ - 3} .$$ This result is discussed in the context of present understanding of hyperon radiative decays.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  7. 7
    Staff View
    ISSN:
    1434-6052
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract In an experiment performed at the CERN-SPS charged hyperon beam, we have observed the radiative decay Λ→nγ, using well identified Λ from the decays of Ο− of 116 GeV/c momentum. Neutrons and photons from the Λ decays were observed in liquid argon and lead glass detectors. From a sample of 31 candidates, containing an estimated background of 7.3 events, the decay branching ratio was measured to be Γ(Λ→nγ)/Γ(Λ→all)=(1.02±0.33)×10−3.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  8. 8
    Staff View
    ISSN:
    1434-6052
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract In an experiment performed at the CERN SPS charged hyperon beam, we have observed the radiative decay Ξ−→∑−γ. From a sample of 11 candidates, containing an estimated background of 1.6 events, the branching ratio is found to be: $$\Gamma (\Xi ^ - \to \Sigma ^ - \gamma )/(\Xi ^ - \to \Lambda \pi ^ - ) = (2.3 \pm 1.0) \times 10^{ - 4} .$$
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  9. 9
    Staff View
    ISSN:
    1434-6052
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract In a experiment at the CERN SPS charged hyperon beam using incident Ξ−, we have obtained evidence for the production of two Ω* resonances decaying into Ξ−π+ K −, with the following parameters:M 1=2251±12,Γ 1=48±20 MeV/c2, 78 ±23 events, andM 2=2284±12,Γ 2=26±23 MeV/c2 45±10 events. The first state is also observed as a 4.2σ effect in a subsample which contains an additionalK + orK 0 in the final state. Production cross sections and branching ratios to Ξ* K − and Ξ− K * are presented.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  10. 10
    Staff View
    ISSN:
    1434-6052
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract In an experiment carried out in the CERN SPS hyperon beam, the diffractive dissociation of incidentΞ − hyperons into ΛK − andΞ −π+π− final states has been observed. Several resonances are seen in the final states, including the well known Ξ(1820) which appears in both channels, and the Ξ(1680) which appears as a narrow state (M=1691.1±2.7 MeV/c2, Γ〈8 MeV/c2) in the ΛK− channel and possibly also in the Ξππ channel.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses