U_A(1) anomaly and eta' mass from an infrared singular quark-gluon vertex
| dc.creator | Alkofer, Reinhard | |
| dc.creator | Fischer, Christian S. | |
| dc.creator | Williams, Richard | |
| dc.date | 2008-04-22 | |
| dc.date | 2008-09-08 | |
| dc.date.accessioned | 2026-07-07T12:14:25Z | |
| dc.date.available | 2026-07-07T12:14:25Z | |
| dc.description | The $U_A(1)$ problem of QCD is inevitably tied to the infrared behaviour of quarks and gluons with its most visible effect being the $η^\prime$ mass. A dimensional argument of Kogut and Susskind showed that the mixing of the pseudoscalar flavour-singlet mesons with gluons can provide a screening of the Goldstone pole in this channel if the full quark-quark interaction is strongly infrared singular as $\sim 1/k^4$. We investigate this idea using previously obtained results for the Landau gauge ghost and gluon propagator, together with recent determinations for the singular behaviour of the quark-gluon vertex. We find that, even with an infrared vanishing gluon propagator, the singular structure of the quark-gluon vertex for certain kinematics is apposite for yielding a non-zero screening mass. | |
| dc.description | 8 pages, 4 figures. Version to appear in EPJA | |
| dc.identifier | https://arxiv.org/abs/0804.3478 | |
| dc.identifier | http://arxiv.org/abs/0804.3478 | |
| dc.identifier | Eur.Phys.J.A38:53-60,2008 | |
| dc.identifier | doi:10.1140/epja/i2008-10646-x | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/211187 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.subject | Nuclear Theory | |
| dc.title | U_A(1) anomaly and eta' mass from an infrared singular quark-gluon vertex | |
| dc.type | text |