Two-Flavor Chiral Perturbation Theory for Hyperons
نویسنده
چکیده
The three-flavor chiral expansion for octet baryons has well-known problems with convergence. We show that this three-flavor chiral expansion can be reorganized into a two-flavor expansion thereby eliminating large kaon and eta loop contributions. Issues of the underlying formulation are addressed by considering the effect of strangeness changing thresholds on hyperon masses. While the spin-3/2 hyperon resonances are considerably more sensitive to these thresholds compared to the spin-1/2 hyperons, we demonstrate that in both cases the essential physics can be captured in the two-flavor effective theory by terms that are analytic in the pion mass squared, but non-analytic in the strange quark mass. Using the two-flavor theory of hyperons, baryon masses and axial charges are investigated. Loop contributions in the two-flavor theory appear to be perturbatively under control. A natural application for our development is to study the pion mass dependence of lattice QCD data on hyperon properties.
منابع مشابه
Hyperon electromagnetic properties in two-flavor chiral perturbation theory
properties in two-flavor chiral perturbation theory. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. The pion-mass dependence of hyperon electromagnetic properties...
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