The pion form factor at timelike momentum transfers in a dispersion approach
| dc.creator | Melikhov, D. | |
| dc.creator | Nachtmann, O. | |
| dc.creator | Paulus, T. | |
| dc.date | 2002-09-13 | |
| dc.date | 2003-01-30 | |
| dc.date.accessioned | 2026-07-07T03:47:57Z | |
| dc.date.available | 2026-07-07T03:47:57Z | |
| dc.description | We consider a model with $ρππ$, $ρKK$, and gauge-invariant $ργ$ couplings and obtain the pion form factor $F_π$ at timelike momentum transfers by resummation of pion and kaon loops. We use a dispersion representation for the loop diagrams and analyse ambiguities related to subtraction constants. The resulting representation for $F_π$ is shown to have the form of the conventional vector meson dominance formula with one important distinction - the effective $ρ$-meson decay constant $f^{\rm eff}_ρ$ turns out to depend on the momentum transfer. For the electromagnetic pion form factor we include in addition the $ρ-ω$ mixing effects. We apply the representations obtained to the analysis of the data on the pion form factors from $e^+e^-$ annihilation and $τ$ decay and extract the $ρ^-$, $ρ^0$ and $ω$ masses and coupling constants. | |
| dc.description | revtex, 12 pages, references added | |
| dc.identifier | https://arxiv.org/abs/hep-ph/0209151 | |
| dc.identifier | http://arxiv.org/abs/hep-ph/0209151 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/41820 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | The pion form factor at timelike momentum transfers in a dispersion approach | |
| dc.type | text |