U_A(1) Problems and Gluon Topology - Anomalous Symmetry in QCD
| dc.creator | Shore, G. M. | |
| dc.date | 1998-12-14 | |
| dc.date.accessioned | 2026-07-07T04:05:59Z | |
| dc.date.available | 2026-07-07T04:05:59Z | |
| dc.description | Many of the distinctive and subtle features of the dynamics in the $U_A(1)$ channel in QCD can be related to gluon topology, more precisely to the topological susceptibility $χ(k^2) = i\int d^4x~e^{ikx}< 0|T~Q(x)~Q(0)|0>$, where $Q = {\a_s\over8π} {\rm tr} G_{\m\n} \tilde G^{\m\n}$ is the gluon topological charge density. The link is the $U_A(1)$ axial (ABJ) anomaly. In this lecture, we describe the anomalous $U_A(1)$ chiral Ward identities in a functional formalism and show how two apparently unrelated `$U_A(1)$ problems' -- the mass of the $η'$ and the violation of the Ellis-Jaffe sum rule in polarised deep-inelastic scattering -- can be explained in terms of the gluon topological susceptibility. They are related through a $U_A(1)$ extension of the Goldberger-Treiman formula, which is derived here for QCD with both massless and massive quarks. | |
| dc.description | Lecture at 1998 Zuoz Summer School, `Hidden Symmetries and Higgs Phenomena'. 22 pages, plain TeX, 2 ps or eps figures | |
| dc.identifier | https://arxiv.org/abs/hep-ph/9812354 | |
| dc.identifier | http://arxiv.org/abs/hep-ph/9812354 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/48607 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | U_A(1) Problems and Gluon Topology - Anomalous Symmetry in QCD | |
| dc.type | text |