排序方式: 共有16条查询结果,搜索用时 15 毫秒
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D. Bisello G. Busetto A. Castro M. Nigro M. Penzo L. Pescara M. Posocco P. Sartori L. Stanco Z. Ajaltouni A. Falvard J. Jousset B. Michel J. C. Montret A. Antonelli R. Baldini A. Calcaterra G. Capon M. Schioppa J. -E. Augustin G. Cosme F. Couchot B. Dudelzak F. Fulda G. Grosdidier B. Jean-Marie S. Jullian D. Lalanne V. Lepeltier F. Manè C. Paulot R. Riskalla Ph. Roy G. Szklarz DM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,39(1):13-19
Thee + e ?→K + K ? cross section has been measured from about 750 events in the energy interval \(1350 \leqq \sqrt s \leqq 2400 MeV\) with the DM2 detector at DCI. TheK ± form factor |F F ±| cannot be explained by the ρ, ω, ? and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment. 相似文献
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J. -E. Augustin G. Cosme F. Couchot B. Dudelzak F. Fulda B. Grelaud G. Grosdidier B. Jean-Marie S. Jullian D. Lalanne V. Lepeltier B. Louis F. Mané C. Paulot R. Riskalla Ph. Roy F. Rumpf G. Szklarz Z. Ajaltouni A. Falvard J. Jousset B. Michel J. C. Montret R. Baldini S. Calcaterra G. Capon D. Bisello G. Busetto S. Limentani M. Nigro L. Pescara M. Posocco P. Sartori L. Stanco DM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,36(3):369-376
The radiative decayJ/ψ → γ π+ π? has been studied using the 8.6 millionJ/ψ produced in the DM2 experiment at the DCIe +e? storage rings at Orsay. The π+ π? mass spectrum shows a cleanf 2 (1270) signal, and the possible presence of two other states at thef 2 (1720) andf 4 (2030) masses. For thef 2 (1270), the branching ratio BR(J/ψ →γf)xBR(f→π+ π?) is measured to be (7.50±0.30±1.12)×10?4, and the spin analysis prefers theJ=2 assignment, with helicity parametersx=0.83±0.06 andy=0.01±0.06. The existence of higher mass states is discussed. 相似文献
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The steady propagation of a thin smouldering front in a half-spacehas been considered. A suitable coordinate transformation hasallowed the region near the leading edge of the front to beexamined for both a maintained planar surface and with surfacecollapse due to material shrinkage. The change in the oxidizerconcentration for a small increment in the propagation speedfor large time and surface collapse has been determined. Theinfluence of two types of nonlinear diffusion on the shape ofthe smouldering front has been found; other cases can be dealtwith in a similar manner. 相似文献
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Hornidge DL Warkentin BJ Igarashi R Bergstrom JC Hallin EL Kolb NR Pywell RE Skopik DM Vogt JM Feldman G 《Physical review letters》2000,84(11):2334-2337
Cross sections for elastic Compton scattering from the deuteron were measured over the laboratory angles straight theta(gamma) = 35 degrees -150 degrees. Tagged photons in the laboratory energy range E(gamma) = 84-105 MeV were scattered from liquid deuterium and detected in the large-volume Boston University NaI spectrometer. Using the calculations of Levchuk and L'vov, along with the measured differential cross sections, the isospin-averaged nucleon polarizabilities in the deuteron were estimated. A best-fit value of (alpha;-beta;) = 2.6+/-1.8 was determined, constrained by dispersion sum rules. This is markedly different from the accepted value for the proton of (alpha;-beta;)(p) = 10.0+/-1.5+/-0.9. 相似文献
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Cross sections and angular distributions for the reaction 12C(γ, d)10B have been measured using solid-state detectors mounted in the focal plane of a magnetic spectrometer. The angular distribution of the deuterons restricted to ground or near ground-state transitions is consistent with an E2 reaction; however at deuteron energies not so restricted the reaction appears to be different from pure E2. Deuteron emission was also studied as a function of incident electron energy. A comparison with simple models is made and an estimate of the 2p-2h contribution to the ground state of 12C is presented. 相似文献
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Dow K Dytman S Beck D Bernstein A Blomqvist I Caplan H Day D Deady M Demos P Dodge W Dodson G Farkhondeh M Flanz J Giovanetti K Goloskie R Hallin E Knill E Kowalski S Lightbody J Lindgren R Maruyama X McCarthy J Quinn B Retzlaff G Sapp W Sargent C Skopik D The I Tieger D Turchinetz W Ueng T Videla N von Reden K Whitney R Williamson C 《Physical review letters》1988,61(15):1706-1709
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The 19F(γ, t)16O reaction was studied over an energy region of 18 to 23 MeV. Two resonances were observed at 18.8 MeV and 20.1 MeV. The angular distribution of tritons from these resonances indicated that the tritons are emitted predominantly in a p-wave, implying ?, or ? with T = for both levels. A comparison with other experiments i the states could be attributed to 16O+t cluster configurations. In addition, from the measured ratio σ(γ, α)/σ(γ, t) ? 0.01 it is concluded that the formation of 15N+α cluster states is small in this region of excitation. 相似文献