40,563 research outputs found
Present status of coupled-channels calculations for heavy-ion subbarrier fusion reactions
The coupled-channels method has been a standard tool in analyzing heavy-ion
fusion reactions at energies around the Coulomb barrier. We investigate three
simplifications usually adopted in the coupled-channels calculations. These are
i) the exclusion of non-collective excitations, ii) the assumption of
coordinate independent coupling strengths, and iii) the harmonic oscillator
approximation for multi-phonon excitations. In connection to the last point, we
propose a novel microscopic method based on the beyond-mean-field approach in
order to take into account the anharmonic effects of collective vibrations.Comment: 10 pages, 4 figures. A talk given at the 12th International
Conference on Nucleus-Nucleus Collisions (NN2015), June 21-26, Catania, Ital
The XYZs of Charmonium at BES
This contribution reviews some recent developments in charmonium
spectroscopy, and discusses related theoretical predictions. The spectrum of
states, strong decays of states above open charm threshold, electromagnetic
transitions, and issues related to the recent discoveries of the "XYZ" states
are discussed. Contributions that BES can make to our understanding of
charmonium and related states are stressed in particular.Comment: 5 pages, 1 eps figure. Invited contribution to the International
Workshop on Tau-Charm Physics Charm2006 (5-7 June 2006, Beijing, China
Summary of Experimental Meson Physics
A summary of the present experimental status of meson physics is presented.
The presentation includes the new results presented at the MESON06 workshop, as
well as other recent experimental developments in the field.Comment: 15 pages, 6 figures, presented at 9th International Workshop on Meson
Production, Properties and Interaction, Krakow, Poland, June 200
Nondecoupling of Heavy Fermions and a Special Yukawa Texture
Talk based on work entitled ``Yukawa textures, new physics and
nondecoupling,'' done in collaboration with G. C. Branco and J. I.
Silva-Marcos, arXiv:hep-ph/0612252, to appear in Phys. Rev. D. In this work we
pointed out that New Physics can play an important r\^ ole in rescuing some of
the Yukawa texture zero ans\" atze which would otherwise be eliminated by the
recent, more precise measurements of . We have shown that the presence
of an isosinglet vector-like quark which mixes with standard quarks, can render
viable a particularly interesting four texture zero Yukawa ansatz. The crucial
point is the nondecoupling of the effects of the isosinglet quark, even for
arbitrary large values of its mass.Comment: Invited talk at CTP Symposium on Supersymmetry at LHC: Theoretical
and Experimental Prospectives, Cairo, Egypt, 11-14 Mar 200
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