0000000000411354
AUTHOR
Junko Yamagata-sekihara
A new perspective on the Faddeev equations and the (K)over-bar N N system from chiral dynamics and unitarity in coupled channels
We review recent work concerning the K¯N interaction and Faddeev equations with chiral dynamics which allow us to look at the K¯NN from a different perspective and pay attention to problems that have been posed in previous studies on the subject. We show results which provide extra experimental evidence on the existence of two Λ(1405) states. We then show the findings of a recent approach to Faddeev equations using chiral unitary dynamics, where an explicit cancellation of the two body off shell amplitude with three body forces stemming from the same chiral Lagrangians takes place. This removal of the unphysical off shell part of the amplitudes is most welcome and renders the approach unamb…
K-bar NN system with chiral dynamics
We have performed a calculation of the scattering amplitude for the three body system K¯NN assuming K¯ scattering against a NN cluster, using the Fixed Center approximation to the Faddeev equations. The K¯N amplitudes, which we take from chiral unitary dynamics, govern the reaction and we find a K¯NN amplitude that peaks around 40 MeV below the K¯NN threshold, with a width in |T|2 of the order of 50 MeV for spin 0 and has another peak around 27 MeV with similar width for spin 1. The results are in line with those obtained using different methods but implementing chiral dynamics. The simplicity of the approach allows one to see the important ingredients responsible for the results. In partic…
Meson and baryon resonances
6 pages, 1 table.-- PACS nrs.: 13.75.Lb, 14.40.Cs, 12.40.Vv, 12.40.Yx.-- Talk at the 2008 International Conference on Particles And Nuclei (PANIC08, Nov 9-14, 2008, Eilat, Israel).
gamma gamma decay of the f(0)(1370) and f(2)(1270) resonances in the hidden gauge formalism
Using recent results obtained within the hidden gauge formalism for vector mesons, in which the f0(1370) and f2(1270) resonances are dynamically generated resonances from the ρρ interaction, we evaluate the radiative decay of these resonances into γγ. We obtain results for the width in good agreement with the experimental data for the f2(1270) state and a width about a factor five smaller for the f0(1370) resonance, which would agree with preliminary results from the Belle collaboration, hinting at an order of magnitude smaller width for this resonance than for the f2(1270).