2018 Impact factor 4.843
Particles and Fields
Eur. Phys. J. C 28, 107-114 (2003)
DOI: 10.1140/epjc/s2003-01140-6

On the mass, width and coupling constants of the f0(980)

R. Escribano1, A. Gallegos2, J.L. Lucio M.2, G. Moreno2 and J. Pestieau3

1  Grup de Física Teòrica and IFAE, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain
2  Instituto de Física, Universidad de Guanajuato, Lomas del Bosque #103, Lomas del Campestre, 37150 León, Guanajuato, Mexico
3  Institut de Physique Théorique, Université Catholique de Louvain, Chemin du Cyclotron 2, 1348 Louvain-la-Neuve, Belgium


(Received: 6 June 2002 / Revised version: 21 October 2002 / Published online: 3 March 2003)

Abstract
Using the pole approach we determine the mass and width of the f0(980); in particular, we analyze the possibility that two nearby poles are associated to it. We restrict our analysis to a neighborhood of the resonance, using $\pi\pi$ data for the phase shift and inelasticity, and the invariant mass spectrum of the $J/\psi\rightarrow\phi\pi\pi, \phi K\bar K$ decays. The formalism we use is based on unitarity and a generalized version of the Breit-Wigner parameterization. We find that a single pole describes the f0(980), the precise position depending upon the $\pi\pi$ data used. As a byproduct, values for the $g_{f_0\pi\pi}$ and $g_{f_0K\bar
K}$ coupling constants are obtained.



© Società Italiana di Fisica, Springer-Verlag 2003