We propose and theoretically study a possible new resonance caused by strong coupling between the Higgs-Higgs and the W_{L}W_{L} (Z_{L}Z_{L}) scattering channels, without regard to the intensity of the elastic interaction in either channel at low energy (that could be weak as in the standard model). We expose this channel-coupling resonance from unitarity and dispersion relations encoded in the inverse amplitude method, applied to the electroweak chiral Lagrangian with a scalar Higgs boson.
View Article and Find Full Text PDFEur Phys J C Part Fields
October 2014
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
September 2013
We present and numerically solve a modified form of the equation of motion for a charged particle under the influence of an external force, taking into account the radiation reaction. This covariant equation is integro-differential, as Dirac-Röhrlich's, but has several technical improvements. First, the equation has the form of Newton's second law, with acceleration isolated on the left hand side and the force depending only on positions and velocities: Thus, the equation is linear in the highest derivative.
View Article and Find Full Text PDFHeavy hadrons containing heavy quarks (for example, Υ mesons) feature a scale separation between the heavy-quark mass and the QCD scale that controls the effective masses of lighter constituents. As in ordinary molecules, the deexcitation of the lighter, faster degrees of freedom leaves the velocity distribution of the heavy quarks unchanged, populating the available decay channels in qualitatively predictable ways. Automatically an application of the Franck-Condon principle of molecular physics explains several puzzling results of Υ(5S) decays as measured by the Belle Collaboration, such as the high rate of Bs*Bs* versus Bs*Bs production, the strength of three-body B*Bπ decays, or the dip in B momentum shown in these decays.
View Article and Find Full Text PDFWe argue that three-quark excited states naturally group into quartets, split into two parity doublets, and that the mass splittings between these parity partners decrease higher up in the baryon spectrum. This decreasing mass difference can be used to probe the running quark mass in the midinfrared power-law regime. A measurement of masses of high-partial-wave Delta* resonances should be sufficient to unambiguously establish the approximate degeneracy.
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