31 July 2018 to 6 August 2018
Maynooth University
Europe/Dublin timezone

Exotic states and their properties in large-Nc QCD

3 Aug 2018, 17:00
20m
Hall A (Arts Bldg.)

Hall A

Arts Bldg.

Talk B: Light quarks Light quarks

Speaker

Dmitri Melikhov (HEPHY)

Description

Discussing four-point Green functions of bilinear quark currents in large-Nc QCD, we formulate rigorous criteria for selecting diagrams appropriate for the analysis of potential tetraquark poles. We find that both flavor-exotic and cryptoexotic (i.e., flavor-nonexotic) tetraquarks, if such poles exist, have a width of order O(1/Nc²), so they are parametrically narrower compared to the ordinary qq mesons, which have a width of order O(1/Nc). Moreover, for flavor-exotic states, the consistency of the large-Nc behavior of “direct” and “recombination” Green functions requires two narrow flavor-exotic states, each coupling dominantly to one specific meson-meson channel.

Primary authors

Wolfgang Lucha (Austrian Academy of Sciences) Dmitri Melikhov (HEPHY) Hagop Sazdjian (University Paris-Sud)

Presentation Materials