The Gauge-Independent QCD Effective Charge
| dc.creator | Watson, N. J. | |
| dc.date | 1996-06-19 | |
| dc.date | 1997-04-01 | |
| dc.date.accessioned | 2026-07-07T11:35:16Z | |
| dc.date.available | 2026-07-07T11:35:16Z | |
| dc.description | It is shown how the QED concept of a gauge-, scale- and scheme-independent one-loop effective charge can be extended directly at the diagrammatic level to QCD, thus justifying explicitly the ``naive non-abelianization'' prescription used in renormalon calculus. It is first argued that, for on-shell external fields and at the strictly one-loop level, the required gluon self-energy-like function is precisely that obtained from S-matrix elements via the pinch technique. The generalization of the pinch technique to explicitly off-shell processes is then introduced. It is shown how, as a result of a fundamental cancellation among conventional perturbation theory diagrams, encoded in the QCD Ward identities, the pinch technique one-loop gluon self-energy i\hatΠ_{μν}^{ab}(q) remains gauge-independent and universal regardless of the fact that the ``external'' fields in the given process are off-shell. This demonstration involves a simple technique enabling the isolation, in an arbitrary gauge, of i\hatΠ_{μν}^{ab}(q) from subclasses of up to several hundred diagrams at once. Furthermore, it is shown how this one-loop cancellation mechanism iterates for the subclasses of n-loop diagrams containing implicitly the Dyson chains of n one-loop self-energies i\hatΠ_{μν}^{ab}(q). The gauge cancellation required for the Dyson summation of i\hatΠ_{μν}^{ab}(q) is thus demonstrated explicitly in a general class of ghost-free gauges for all orders n. | |
| dc.description | 48 pages, Latex, uses axodraw.sty (included). Revised to include throughout the case of non-covariant gauges too | |
| dc.identifier | https://arxiv.org/abs/hep-ph/9606381 | |
| dc.identifier | http://arxiv.org/abs/hep-ph/9606381 | |
| dc.identifier | Nucl.Phys.B494:388-432,1997 | |
| dc.identifier | doi:10.1016/S0550-3213(97)00179-X | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/198534 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | The Gauge-Independent QCD Effective Charge | |
| dc.type | text |