Funds: Supported in part by the the Ministerio de Ciencia e Innovación(FPA201125948), the Ministerio de Economíia y Competitividad(CICYT-FEDER-FPA 2014-55613-P, SEV-2012-0234), the Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya(2014 SGR 1450), the Spanish Consolider-Ingenio 2010 Programme CPAN(CSD2007-00042)
A combined analysis of the space- and time-like experimental data for the η transition form factor is performed in a model-independent way by means of rational approximants. The recent measurement of the e+e- invariant mass spectrum of the η→e+e--γ decay provided by the A2 Collaboration allowed us to extract the most precise and up-to-date slope and curvature parameters of the form factor. The impact of this new analysis on the ηη′ mixing parameters and the VPγ couplings is also discussed.
Abstract
A combined analysis of the space- and time-like experimental data for the η transition form factor is performed in a model-independent way by means of rational approximants. The recent measurement of the e+e- invariant mass spectrum of the η→e+e--γ decay provided by the A2 Collaboration allowed us to extract the most precise and up-to-date slope and curvature parameters of the form factor. The impact of this new analysis on the ηη′ mixing parameters and the VPγ couplings is also discussed.