The strong coupling constant, αs, has been determined in hadronic decays of theZ0 resonance, using measurements of seven observables relating to global event shapes, energy correlatio
Data corrected for finite acceptance and resolution of the detector and for intial state photon radiation. No corrections for hadronic effects are applied.. Errors include statistical and systematic uncertainties, added in quadrature.
Data corrected for finite acceptance and resolution of the detector and for intial state photon radiation. No corrections for hadronic effects are applied.. Errors include statistical and systematic uncertainties, added in quadrature.
Data corrected for finite acceptance and resolution of the detector and for intial state photon radiation. No corrections for hadronic effects are applied.. Errors include statistical and systematic uncertainties, added in quadrature.
The value of the strong coupling constant,$$\alpha _s (M_{Z^0 } )$$, is determined from a study of 15 d
Differential jet mass distribution for the heavier jet using method T. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.
Differential jet mass distribution for the jet mass difference using methodT. The data are corrected for the finite acceptance and resolution of the detec tor and for initial state photon radiation.
Differential jet mass distribution for the heavier jet using method M. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.
About 15 000 K − Φp events have been collected in the CERN Ω′ spectrometer. A partial-wave decomposition of the K − Φ system is performed. The 1 + SO + wave is dominant. The 0 − P0 + and 2 − P0 + waves are important and show resonant behaviour at ∼ 1.83 GeV (Γ ∼ 0.25 GeV) and ∼ 1.73 GeV (Γ ∼ 0.22 GeV) respectively. The first one can be interpreted as the second radial excitation of the kaon while the second one can be identified as one of the two L mesons.
No description provided.
PARTIAL WAVE AMPLITUDE SHOWING POSSIBLE EXISTENCE OF L MESON AT 1.73 GEV (WIDTH = 0.22 GEV) AND RADIAL EXCITATION OF THE KAON AT 1.83 GEV (WIDTH = 0.25 GEV).
The production ofK* resonances has been studied in the reaction\(K^ -p \to \bar K^0 \pi ^ -p\) at 8.25 GeV/c. The data comes from a high statistics bubble chamber experiment (180 events/μb). Masses, widths and production cross-sections have been determined for the first threeK*'s. The contributions from natural and unnatural parity exchange have been obtained for theK*(890) and theK*(1420). A partial wave analysis of theK π system from threshold to 1.9 GeV provides evidence for a 0+ enhancement near 1.4 GeV which could be interpreted as the κ(1350).
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FULLY CORRECTED.
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We have studied the reactions\(\bar pn \to \pi ^ -\pi ^ -\pi ^ +(\pi ^0 )\) at incident momenta between 0.42 and 1.65 GeV/c using two exposures in deuterium-filled bubble chambers. The ratio of the rates for 3π to 4π final states shows a sharp increase at a momentum of about 0.8 GeV/c. A full partial-wave analysis of the 3π final state has been made and complex structure is observed at approximately the same momentum, associated in particular with theJP=3+ final state.
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We have measured the electron, muon, and charged-hadron pair production rates in two-phonon interactions for invariant masses above 2.0 GeV over a large of momentum transfer. The cross sections for electron and muon pairs show good agreement with the QED predictions at both small and large momentum transfer. The observed rate of hadron production is less than 6% of the rate that QED predicts for point-like hadrons, consistent with recent leading-order QCD calculations.
LOW Q**2 CROSS SECTIONS.
DIFFERENTIAL CROSS SECTIONS IN THE INVARIANT MASS FOR MUON AND ELECTRON PAIRS IN THE UNTAGGED, LOW Q**2 REGION.
HIGH Q**2 CROSS SECTIONS.
DATA WITHOUT MOMENTUM REJECTION.
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None
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We have carried out an amplitude analysis of the KS0KS0 system produced in the reaction π−p→KS0KS0n at 23 GeV/c, based on about 15 000 events in the low-t region (|t−tmin|<0.1 GeV2). Below 1.6 GeV/c2, our favored solution is very similar to those from previous analyses. For higher masses, we observe the KS0KS0 decay of the h(2040) meson. In addition, the l=0 partial wave contains a new state, strongly coupled to KS0KS0, with parameters M=1.771−0.053+0.077 GeV/c2 and Γ=0.200−0.009+0.156 GeV/c2. Since this state is most probably I=0, we call it the S*′(1770). We find an f′f production ratio of 0.23−0.13+0.14, and branching ratios for f-meson and h(2040)-meson decays into KK¯ of (3.1−1.7+0.7)% and (0.67−0.15+0.41)%, respectively. We find, in a detailed comparison of our results with those from other experiments, that our solution is compatible with all known features of both charged and neutral KK¯ systems.
No description provided.
The reaction K − p → K − π − π + p has been measured at 25 and 40 GeV/ c at the Serpukhov Proton Accelerator. The production cross section at 25 and 40 GeV/ c as a function of momentum transfer and K ππ mass is presented, and results of the partial-wave analysis of the K ππ system yielding information about Q(1300), K ∗ (1400) and L(1770) mesons are discussed.
No description provided.
K** DEFINED BY 1.30 < M(K PI PI) < 1.54 GEV.
L IS DEFINED AS THE 2- STATE WITH 1.6 < M(K PI PI) < 1.9 GEV.
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