R. Ayad

Bounds on the CP Asymmetry in b {r_arrow} s{gamma} Decays

We have measured the CP asymmetry A(CP) identical with[gamma(b-->sgamma)-gammab-->sgamma)]/[gamma(b-->sgamma)+gamma(b-->sgamma)] to be A(CP) = (-0.079+/-0.108+/-0.022) (1.0+/-0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model.

Study of Deconfinement Phase Transition in Heavy Ion Collisions at BNL Energies

Abstract — The Scaled factorial moments (SFMs) of multiplicity distribution are used to study the deconfinement phase transition in high energy heavy-ion collisions. In the present article we studied the Renyi dimensions and multifractal spectrum in the interaction of 28 S-emulsion collisions at 14.6A GeV to investigate non thermal phase transitions during such collisions. Index Terms — Novel state of matter, quark-gluon plasma (QGP), scaled factorial moments (SFMs). I. I NTRODUCTION During last couple of years, different nuclei have been accelerated to relativistic energies and brought to collisions with a great variety of target nuclei. An ultimate aim of studying nucleus – nucleus (A-A) collisions is to investigate for a phenomena connecting with large densities obtained in such nuclear collisions. So due to this one can obtained an opportunity to explore strongly interacting matter at energy densities unprecedented in a laboratory, which eventually gives an evidence for the existence of quark-gluon plasma (QGP). The QGP is a novel state of matter in which quarks and gluons are no longer confined to volumes of hadronic dimensions. In deep inelastic scattering experiments, it has already been revealed that quarks at very short distances move freely, which is referred to as the asymptotic freedom. Quantum Chromo-dynamics (QCD) describes the strong interactions of quarks and gluons [1]. The experimental observation of large rapidity fluctuations in relativistic heavy ion collisions by R. C. Hwa and J. C. Pan [2], [3] using the method of multifractal moments method,

Search for the Decay B(bar sign){sup 0}{yields} D{sup *0}{gamma}

We report results of a search for the rare radiative decay B0 ->D*0 gamma. Using 9.7 million BB meson pairs collected with the CLEO detector at the Cornell Electron Storage Ring, we limit Br(B0->D*0 gamma)<5.0 * 10^-5 at 90% CL. This provides evidence that anomalous enhancement is absent in W-exchange processes and that weak radiative B decays are dominated by the short-distance b ->s gamma mechanism in the Standard Model.

First Observation of the Decay B →J/ψϕK

We present the first observation of the decay B->J/psi phi K. Using 9.6 million B meson pairs collected with the CLEO detector, we have observed 10 fully reconstructed B->J/psi phi K candidates, whereas the estimated background is 0.5+/-0.2 events. We obtain a branching fraction of Br(B->J/psi phi K) = (8.8+3.5/-3.0(stat)+/-1.3(syst))*10^-5. This is the first observed

Observation of new states decaying into Lambda(+)(c)pi(-)pi(+)

B

Beamstrahlung Radiation for Beam-Beam Instability

meson decay requiring the creation of an additional s sbar quark pair.