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Journal articleAckerstaff K, Alexander G, Allison J, et al., 1999,
Measurements of flavour-dependent fragmentation functions in Z<sup>0</sup> → qq̄ events
, European Physical Journal C, Vol: 7, Pages: 369-381, ISSN: 1434-6044Fragmentation functions for charged particles in Z0 → qq̄ events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed D*± mesons and secondary vertices. The ξP = ln(1/xp) distributions and the position of their maxima ξ0 are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks.
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Journal articleAbbiendi G, Ackerstaff K, Alexander G, et al., 1999,
Bose-Einstein correlations in e<sup>+</sup>e<sup>-</sup> → W<sup>+</sup>W<sup>-</sup> at 172 and 183 GeV
, European Physical Journal C, Vol: 8, Pages: 559-571, ISSN: 1434-6044Bose-Einstein correlations between like-charge pions are studied in hadronic final states produced by e+e- annihilations at center-of-mass energies of 172 and 183 GeV. Three event samples are studied, each dominated by one of the processes W+W- →qq̄ℓν̄e, W+W- qq̄qq̄, or (Z0/γ)* → qq̄. After demonstrating the existence of Bose-Einstein correlations in W decays, an attempt is made to determine Bose-Einstein correlations for pions originating from the same W boson and from different W bosons, as well as for pions from (Z0/γ)* → qq̄ events. The following results are obtained for the individual chaoticity parameters λ, assuming a common source radius R: λsame= 0.63 ± 0.19 ± 0.14 λdiff = 0.22 ± 0.53 ±0.14, λ Z* = 0.47 ± 0.11 ± 0.08, R = 0.92 ± 0.09 ± 0.09 fm. In each case, the first error is statistical and the second is systematic. At the current level of statistical precision it is not established whether Bose-Einstein correlations, between pions from different W bosons exist or not.
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Journal articleAckerstaff K, Alexander G, Allison J, et al., 1999,
Production of K<sup>0</sup><inf>S</inf> and Λ in quark and gluon jets from Z<sup>0</sup> decay
, European Physical Journal C, Vol: 8, Pages: 241-254, ISSN: 1434-6044The production of K0S mesons and Λ baryons in quark and gluon jets has been investigated using two complementary techniques. In the first approach, which provides high statistical accuracy, jets were selected using different jet finding algorithms and ordered according to their energy. Production rates were determined taking into account the dependences of quark and gluon compositions as a function of jet energy as predicted by Monte Carlo models. Selecting three-jet events with the k⊥ (Durham) jet finder (Ycut = 0.005), the ratios of K0S and Λ production rates in gluon and quark jets relative to the mean charged particle multiplicity were found to be 1.10 ± 0.02 ± 0.02 and 1.41 ± 0.04 ± 0.04, respectively, where the first uncertainty is statistical and the second is systematic. In the second approach, a new method of identifying quark jets based on the collimation of energy flow around the jet axis is introduced and was used to anti-tag gluon jets in symmetric (Y-shaped) three-jet events. Using the cone jet finding algorithm with a cone size of 30°, the ratios of relative production rates in gluon and quark jets were determined to be 0.94 ± 0.07 ± 0.07 for K0S and 1.18 ± 0.10 ± 0.17 for Λ. The results of both analyses are compared to the predictions of Monte Carlo models.
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Conference paperDavies G J, 1999,
RECENT RESULTS FROM PBWO4 CRYSTALS AND MSGCS IN CMS
, European Physical Society, 1997, Pages: 1109-1113 -
Journal articleAbreu P, Adye T, Adzic P, et al., 1999,
Search for pair-produced neutralinos in events with photons and missing energy from e<SUP>+</SUP>e<SUP>-</SUP> collisions at √<i>s</i>=130-183 GeV
, EUROPEAN PHYSICAL JOURNAL C, Vol: 6, Pages: 371-384, ISSN: 1434-6044- Author Web Link
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- Citations: 10
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Journal articleAbbiendi G, Ackerstaff K, Alexander G, et al., 1999,
Tests of the Standard Model and constraints on new physics from measurements of fermion-pair production at 183 GeV at LEP
, EUROPEAN PHYSICAL JOURNAL C, Vol: 6, Pages: 1-18, ISSN: 1434-6044- Author Web Link
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- Citations: 87
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Journal articleTorii HA, Hayano RS, Hori M, et al., 1999,
Laser measurements of the density shifts of resonance lines in antiprotonic helium atoms and stringent constraint on the antiproton charge and mass
, PHYSICAL REVIEW A, Vol: 59, Pages: 223-229, ISSN: 1050-2947- Author Web Link
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- Citations: 80
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Journal articleBarate R, Buskulic D, Decamp D, et al., 1999,
Determination of |V<sub>ub</sub>| from the measurement of the inclusive charmless semileptonic branching ratio of b hadrons
, EUROPEAN PHYSICAL JOURNAL C, Vol: 6, Pages: 555-574, ISSN: 1434-6044- Author Web Link
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- Citations: 53
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Journal articleAckerstaff K, Alexander G, Allison J, et al., 1999,
Search for scalar top and scalar bottom quarks at √s = 183 GeV at LEP
, EUROPEAN PHYSICAL JOURNAL C, Vol: 6, Pages: 225-238, ISSN: 1434-6044- Author Web Link
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- Citations: 16
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Journal articleAbreu P, Adam W, Adye T, et al., 1999,
Measurement of the quark and gluon fragmentation functions in Z<SUP>0</SUP> hadronic decays
, EUROPEAN PHYSICAL JOURNAL C, Vol: 6, Pages: 19-33, ISSN: 1434-6044- Author Web Link
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- Citations: 39
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Journal articleAbreu P, Adam W, Adye T, et al., 1999,
Search for scalar fermions and long-lived scalar leptons at centre-of-mass energies of 130 GeV to 172 GeV
, EUROPEAN PHYSICAL JOURNAL C, Vol: 6, Pages: 385-401, ISSN: 1434-6044- Author Web Link
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- Citations: 23
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Conference paperSumner TJ, Quenby JJ, Bewick A, et al., 1999,
Current limits on the cold dark matter interaction cross section obtained by the UK collaboration
, 5th International Workshop on Topics in Astroparticle and Underground Physics (TAUP 97), Publisher: ELSEVIER SCIENCE BV, Pages: 74-78, ISSN: 0920-5632- Author Web Link
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- Citations: 11
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Journal articleAckerstaff K, Alexander G, Allison J, et al., 1999,
Inclusive production of charged hadrons and K<SUP>0</SUP><sub>S</sub> mesons in photon-photon collisions
, EUROPEAN PHYSICAL JOURNAL C, Vol: 6, Pages: 253-264, ISSN: 1434-6044- Author Web Link
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- Citations: 23
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Journal articlePetrascu C, Bianco S, Bragadireanu AM, et al., 1999,
, Hyperfine Interactions, Vol: 118, Pages: 53-57
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Journal articleBreitweg J, Sideris D, 1999,
Measurement of jet shapes in high Q**2 deep inelastic scattering at HERA
, Eur.Phys.J., Vol: C8, Pages: 367-380 -
Conference paperIchioka T, Higaki H, Hori M, et al., 1999,
Multi-ring trap as a reservoir of cooled antiprotons
, Workshop on Non-Neutral Plasma Physics, Publisher: AMER INST PHYSICS, Pages: 59-64, ISSN: 0094-243X- Author Web Link
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- Citations: 6
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Journal articleAbbiendi et al G, 1999,
Measurements of the QED structure of the photon
, The European Physical Journal C, Vol: 11, Pages: 409-409, ISSN: 1434-6044 -
Journal articleAbbiendi et al G, 1999,
Experimental properties of gluon and quark jets from a point source
, The European Physical Journal C, Vol: 11, Pages: 217-217, ISSN: 1434-6044 -
Journal articleAbbiendi et al G, 1999,
Search for anomalous photonic events with missing energy in
, The European Physical Journal C, Vol: 8, Pages: 23-23, ISSN: 1434-6044 -
Journal articleAbbiendi et al G, 1999,
Searches for R-parity violating decays of Gauginos at 183 GeV at LEP
, The European Physical Journal C, Vol: 11, Pages: 619-619, ISSN: 1434-6044 -
Journal articleAbbiendi et al G, 1999,
Intermittency and correlations in hadronic Z
, The European Physical Journal C, Vol: 11, Pages: 239-239, ISSN: 1434-6044 -
Journal articleAbbiendi et al G, 1999,
A study of
, The European Physical Journal C, Vol: 11, Pages: 587-587, ISSN: 1434-6044 -
Journal articleAbbiendi et al G, 1999,
Test of the flavour independence of
, The European Physical Journal C, Vol: 11, Pages: 643-643, ISSN: 1434-6044 -
Journal articleBarate et al R, 1999,
Study of
, The European Physical Journal C, Vol: 11, Pages: 599-599, ISSN: 1434-6044 -
Journal articleBarate et al R, 1999,
Search for charginos and neutralinos in e
, The European Physical Journal C, Vol: 11, Pages: 193-193, ISSN: 1434-6044 -
Journal articleBarate et al R, 1999,
Search for supersymmetry with a dominant R-parity violating
, The European Physical Journal C, Vol: 7, Pages: 383-383, ISSN: 1434-6044 -
Journal articleBarate et al R, 1999,
Search for
, The European Physical Journal C, Vol: 7, Pages: 553-553, ISSN: 1434-6044 -
Journal articleBreitweg et al J, 1999,
Measurement of multiplicity and momentum spectra in the current and target regions of the Breit frame in Deep Inelastic Scattering at HERA
, The European Physical Journal C, Vol: 11, Pages: 251-251, ISSN: 1434-6044 -
Journal articleBreitweg et al J, 1999,
Exclusive electroproduction of
, The European Physical Journal C, Vol: 6, Pages: 603-603, ISSN: 1434-6044 -
Journal articleBreitweg et al J, 1999,
ZEUS results on the measurement and phenomenology of
, The European Physical Journal C, Vol: 7, Pages: 609-609, ISSN: 1434-6044
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