Szczegóły publikacji
Opis bibliograficzny
Multi-photon production in $e^{+}e^{-}$ collisions at $\sqrt{s}$=189 GeV / G. Abbiendi [et al.], M. PRZYBYCIEŃ [et al.] // Physics Letters. B, Nuclear Elementary Particle and High-Energy Physics ; ISSN 0370-2693. — 1999 — vol. 465 iss. 1–4, s. 303–314. — Bibliogr. s. 314, Abstr. — Publikacja dostępna online od: 12000-01-06. — M. Przybycień - pierwsza afiliacja: CERN, Geneva, Switzerland
Autorzy (317)
- AGHPrzybycień Mariusz
- Abbiendi Giovanni
Dane bibliometryczne
| ID BaDAP | 2737 |
|---|---|
| Data dodania do BaDAP | 2001-04-18 |
| Tekst źródłowy | URL |
| DOI | 10.1016/S0370-2693(99)01092-8 |
| Rok publikacji | 1999 |
| Typ publikacji | artykuł w czasopiśmie |
| Otwarty dostęp |  |
| Czasopismo/seria | Physics Letters, B |
Abstract
The process e(+)e(-) –> gamma gamma(gamma) is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb(-1). The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda(+)> 304 GeV and Lambda(-)> 295 GeV as well as a mass limit for an excited electron, M-e * > 306 GeV assuming equal e*e gamma and ee gamma couplings. Graviton exchange in the context of theories with higher dimensions is excluded for scales G(+)< 660 GeV and G(-)< 634 GeV. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons and produced in association with another photon. (C) 1999 Published by Elsevier Science B.V. All rights reserved.
