8,789 research outputs found

    Ultra-Peripheral Collisons in CMS

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    Coherent peripheral collisions of atomic nuclei involve electromagnetic or long range hadronic interactions at impact parameters, where both nuclei survive intact. Recently such ultra-peripheral collisions were observed at RHIC. The effect of the electromagnetic field can be interpreted as a photon-photon collision with an effective center of mass energy up to a few GeV at RHIC. At the Large Hadron Collider the effective center of mass energy will be increased by more than an order of magnitude. This opens new opportunities, ranging from the study of non-perturbative QCD to the search for new physics

    Can Conformal Weyl Gravity be Considered a Viable Cosmological Theory?

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    We present exact analytical solutions to the Conformal Weyl Gravity cosmological equations that are valid for both the matter and radiation dominated eras. The Primordial Nucleosynthesis process is also exhaustively studied. The main conclusion of our work is that cosmological models derived from this theory are not likely to reproduce the observational properties of our Universe. They fail to fulfill simultaneously the observational constraints on present cosmological parameters and on primordial light element abundances.Comment: 7 pages, (1 Figure included), uuencode compressed Postscript. (To be published in ApJ, June 1994.). FTUAM-93-2
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