SU(3) quark-antiquark QCD flux tube

We compute the quark-antiquark flux tube for pure gauge SU(3) in space-time 3 + 1 dimensions. To increase the signal over noise ratio, we apply the improved multihit and extended smearing techniques. We fit the field densities with an appropriate ansatz and we observe both the screening of the color fields and the quantum widening of the flux tube in the mediator plane and in the charge planes.Comment: 7 pages, 8 figures, poster presented at the 31st International Symposium on Lattice Field Theory, July 29 - August 3, 2013, Mainz, German

Colour Fields Computed in SU(3) Lattice QCD for the Static Tetraquark System

The colour fields created by the static tetraquark system are computed in quenched SU(3) lattice QCD, in a 24^3 x 48 lattice at beta=6.2 corresponding to a lattice spacing a=0.07261(85) fm. We find that the tetraquark colour fields are well described by a double-Y, or butterfly, shaped flux tube. The two flux tube junction points are compatible with Fermat points minimizing the total flux tube length. We also compare the diquark-diantiquark central flux tube profile in the tetraquark with the quark-antiquark fundamental flux tube profile in the meson, and they match, thus showing that the tetraquark flux tubes are composed of fundamental flux tubes.Comment: 5 pages, 7 figures, 0 tables, one reference added, work done partly under the PT-LQCD Collaboratio