Momentum dependence of the topological susceptibility with overlap fermions
Abstract
Knowledge of the derivative of the topological susceptibility at zero momentum is important for assessing the validity of the Witten-Veneziano formula for the eta' mass, and likewise for the resolution of the EMC proton spin problem. We investigate the momentum dependence of the topological susceptibility and its derivative at zero momentum using overlap fermions in quenched lattice QCD simulations. We expose the role of the low-lying Dirac eigenmodes for the topological charge density, and find a negative value for the derivative. While the sign of the derivative is consistent with the QCD sum rule for pure Yang-Mills theory, the absolute value is overestimated if the contribution from higher eigenmodes is ignored.
- Publication:
-
Proceedings of The XXVIII International Symposium on Lattice Field Theory. June 14-19
- Pub Date:
- 2010
- DOI:
- 10.22323/1.105.0278
- arXiv:
- arXiv:1012.1383
- Bibcode:
- 2010slft.confE.278K
- Keywords:
-
- High Energy Physics - Lattice
- E-Print:
- 7 pages, Talk presented at the 28th International Symposium on Lattice Field Theory (Lattice 2010), June 14-19,2010, Villasimius, Sardinia, Italy