TY - JOUR

T1 - Multi-photon production in e+ e- collisions at √s=183 GeV

AU - Kartvelishvili, Vakhtang

AU - OPAL Collaboration

PY - 1998/10/22

Y1 - 1998/10/22

N2 - The process e e q y™gg gŽ . is studied using data recorded with the OPAL detector at LEP. The data sample correspondsto a total integrated luminosity of 56.2 pby1 taken at a centre-of-mass energy of 183 GeV. The measured cross-sectionagrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL onthe QED cut-off parameters: Lq y ) 233 GeV and L ) 265 GeV as well as a mass limit for an excited electron, Me))227 GeV assuming equal e)eg and eeg couplings. No evidence for resonance production is found in the invariant massspectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into twophotons.

AB - The process e e q y™gg gŽ . is studied using data recorded with the OPAL detector at LEP. The data sample correspondsto a total integrated luminosity of 56.2 pby1 taken at a centre-of-mass energy of 183 GeV. The measured cross-sectionagrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL onthe QED cut-off parameters: Lq y ) 233 GeV and L ) 265 GeV as well as a mass limit for an excited electron, Me))227 GeV assuming equal e)eg and eeg couplings. No evidence for resonance production is found in the invariant massspectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into twophotons.

U2 - 10.1016/S0370-2693(98)01096-X

DO - 10.1016/S0370-2693(98)01096-X

M3 - Journal article

VL - 438

SP - 379

EP - 390

JO - Physics Letters B

JF - Physics Letters B

SN - 0370-2693

IS - 3-4

ER -