@Article{Albaladejo+Moussallam2015,
author="Albaladejo, M.
and Moussallam, B.",
title="Form factors of the isovector scalar current and the eta pi scattering phase shifts",
journal="European Physical Journal C",
year="2015",
publisher="Springer",
volume="75",
number="10",
pages="488 - 16pp",
abstract="A model for S-wave eta pi scattering is proposed which could be realistic in an energy range from threshold up to above 1 GeV, where inelasticity is dominated by the K (K) over bar channel. The T-matrix, satisfying two-channel unitarity, is given in a form which matches the chiral expansion results at order p(4) exactly for the eta pi -> eta pi, eta pi -> K (K) over bar amplitudes and approximately for K (K) over bar -> K (K) over bar. It contains six phenomenological parameters. Asymptotic conditions are imposed which ensure a minimal solution of the Muskhelishvili-Omnes problem, thus allowing one to compute the eta pi and K (K) over bar form factor matrix elements of the I = 1 scalar current from the T-matrix. The phenomenological parameters are determined such as to reproduce the experimental properties of the a(0)(980), a(0)(1450) resonances, as well as the chiral results of the eta pi and K (K) over bar scalar radii, which are predicted to be remarkably small at O(p(4)). This T-matrix model could be used for a unified treatment of the eta pi final-state interaction problem in processes such as eta {\textquoteright} -> eta pi pi, phi -> eta pi gamma or the eta pi initial-state interaction in eta -> 3 pi.",
optnote="WOS:000362951600001",
optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=2415), last updated on Thu, 05 Nov 2015 12:12:07 +0000",
issn="1434-6044",
doi="10.1140/epjc/s10052-015-3715-z",
opturl="http://arxiv.org/abs/1507.04526",
opturl="https://doi.org/10.1140/epjc/s10052-015-3715-z",
archivePrefix="arXiv",
eprint="1507.04526",
language="English"
}