Előadó: George Rupp (CFTP, Lisbon)
Előadás címe: Scalar-Meson Pole Trajectories
Dátum: 2024. május 6. hétfő, 11.00 óra
Helyszín: 3-es épület, nagy előadóterem
Összefoglaló:
The light scalar mesons have been haunting both theorists and experimentalists for many years, as their low masses cannot be understood in the context of the static constituent quark model. This led R.L. Jaffe in 1977 to suggest a description in terms of tetraquark configurations, thus allowing to obtain scalar-meson masses below 1 GeV owing to a very large and attractive colour-hyperfine interaction. However, a few years later my co-authors and I showed that the light scalar mesons can be reproduced as dynamical quark-antiquark resonances, provided that the effects of strong decay are included non-perturbatively. This has been confirmed in recent years with lattice simulations.
In models and on the lattice, much can be learned about the nature of the scalar mesons from their mass dependence on coupling constants or the employed pion mass. Thus, in the present talk I shall present model results for scalar-meson pole trajectories, both as a function of overall coupling and of pion mass, the latter allowing to compare with the lattice. The first part of my talk will briefly summarise a contribution to the Gribov-90 Memorial Volume, inspired by Gribov's suggestion of novel mesons as scalar vacuum excitations of a condensate of light quark-antiquark pairs.
