Colour Reconnection at LEPII

The preliminary results on the search of colour reconnection effects (CR) from the four experiments at LEP, Aleph, Delphi, L3 and Opal, are reviewed. Extreme models are excluded by studies of standard variables, and on going studies of a method first suggested by L3, the particle flow method, are yet inconclusive.Comment: 8 pages, 6 figures (1 in eps, 5 in ps) talk given at XXXI International Symposium on Multiparticle Dynamics, Sep. 1-7, 2001, Datong China URL http://ismd31.ccnu.edu.cn

The Physics of UHECRs: Spectra, Composition and the Transition Galactic-Extragalactic

We review the experimental evidences about flux and mass composition of ultra high energy cosmic rays in connection with theoretical scenarios concerning astrophysical sources. In this context, we also address the discussion about the expected transition between cosmic rays produced inside the Galaxy and those coming from the intergalactic space.Comment: 6 pages, 10 figures, invited talk given at the "2016 International Conference on Ultra-High Energy Cosmic Rays (UHECR2016)", Kyoto (Japan), 11-14 October 2016, version accepted for publication on JPS Conference Proceeding

B Physics at the Z0 Resonance

B physics results from e+ e- annihilation at the Z0 resonance are reviewed. A vast program is summarised, including the study of B+, B0d, B0s and b baryon lifetimes, the time dependence of B0d and B0s oscillations, the width difference in the B0s system, and the measurements of the magnitudes of the CKM matrix elements Vcb and Vub.Comment: 17 pages, 8 figures, presented at the UK Phenomenology Workshop on Heavy Flavour and CP Violation, 17-22 September 200

A model-independent analysis of the dependence of the anomalous J/psi suppression on the number of participant nucleons

A recently published experimental dependence of the J/psi to Drell-Yan ratio on the measured, by a zero degree calorimeter, forward energy E_ZDC in Pb+Pb collisions at the CERN SPS is analyzed. Using a model-independent approach it is shown that the data are at variance with an earlier published experimental dependence of the same quantity on the transverse energy of neutral hadrons E_T. The discrepancy is related to a moderate centrality region: 100 < N_p < 200 (N_p is the number of participant nucleons) and is peculiar only to the data obtained within the `minimum bias' analysis (using the `theoretical Drell-Yan'). This could result from systematic experimental errors in the minimum bias sample. A possible source of the errors is discussed.Comment: 10 pages, LaTeX, 3 PS-figures. V2: Misprints are correcte

Fragmentation Function Method for Charge Asymmetry Measurements in \e^+e^- Collisions

We propose a method for measuring the hadron charge asymmetry in \ee collisions which is based upon the fragmentation function formalism, and is largely independent of modelling of fragmentation effects. Furthermore, in this method, QCD radiative corrections can be accounted for in a systematic way.Comment: 11 pages, 4 figures, Latex, CERN-TH.7212/9

Battery simulation program

Computer program calculates spacecraft battery energy at specific times dictated by input sequence of recharge, discharge, and no activity phases. Recharge phases are assumed during times not specified, unless batteries are fully charged. Warnings are printed when energy falls below specified level. Program assumes two identical batteries

(Non)Thermal Aspects of Charmonium Production and a New Look at J/ψ\psi Suppression

To investigate a recent proposal that J/$\psi$ production in ultra-relativistic nuclear collisions is of thermal origin we have reanalyzed the data from the NA38/50 collaboration within a thermal model including charm. Comparison of the calculated with measured yields demonstrates the non-thermal origin of hidden charm production at SPS energy. However, the ratio $\psi^{'}$/(J/$\psi)$ exhibits, in central nucleus-nucleus collisions, thermal features which lead us to a new interpretation of open charm and charmonium production at SPS energy. Implications for RHIC and LHC energy measurements will be discussed.Comment: 12 pages, 3 eps figures, final version with slight corrections, Phys. Lett. B (in print

Beam-Beam with a few long range encounters at short distance

The high nominal luminosity of the LHC requires a large number of bunches spaced by about 25 ns. To prevent more than one head-on collision in each interaction region, a total crossing angle of 0.285 mrad is necessary, and the bunches experience around 30 long range (LR) interactions per IP with at mean separation of 9.5 s. For the LHC luminosity upgrade, there are two possible scenarios: the early separation scheme and low Piwinski angle (LPA) scheme. In the early separation scheme, a few long range interactions need to be tolerated, this paper the discuss the possibility of having a few LR encounters at a minimum separation smaller than the 9 s, and present observations from other hadron machines with a smaller beam separation

Spin Alignment of Heavy Meson Revisited

Using heavy quark effective theory a factorized form for inclusive production rate of a heavy meson can be obtained, in which the nonperturbative effect related to the heavy meson can be characterized by matrix elements defined in the heavy quark effective theory. Using this factorization, predictions for the full spin density matrix of a spin-1 and spin-2 meson can be obtained and they are characterized only by one coefficient representing the nonperturbative effect. Predictions for spin-1 heavy meson are compared with experiment performed at $e^+e^-$ colliders in the energy range from $\sqrt{s}=10.5$GeV to $\sqrt{s}=91$GeV, a complete agreement is found for $D^*$- and $B^*$-meson. There are distinct differences from the existing approach and they are discussed.Comment: 6 pages, Talk given at 3rd Circum-Pan-Pacific Symposium on "High Energy Spin Physics", Beijing, China, 8-13, 200

Diagnóstico bioclimático para a Mesorregião Centro Norte de Mato Grosso do Sul.

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