The η′ in baryon chiral perturbation theory
نویسنده
چکیده
We include in a systematic way the η′ in baryon chiral perturbation theory. The most general relativistic effective Lagrangian describing the interaction of the lowest lying baryon octet with the Goldstone boson octet and the η′ is presented up to linear order in the derivative expansion and its heavy baryon limit is obtained. As explicit examples, we calculate the baryon masses and the πN σ-term up to one-loop order in the heavy baryon formulation. A systematic expansion in the meson masses is possible, and appearing divergences are renormalized. Work supported in part by the BMBF email: [email protected]
منابع مشابه
Wave Function Renormalization in Heavy Baryon Chiral Perturbation Theory*
We establish exact relations between relativistic form factors and amplitudes for single– baryon processes and the corresponding quantities calculated in the framework of heavy baryon chiral perturbation theory. A crucial ingredient for the proper matching is the first complete treatment of baryon wave function renormalization in heavy baryon chiral perturbation theory. * Work supported in part...
متن کاملar X iv : h ep - p h / 01 05 03 3 v 1 3 M ay 2 00 1 Threshold η and η ′ electroproduction off nucleons 1
The electroproduction of η and η ′ mesons on the proton and the neutron is investigated at tree level within the framework of U (3) chiral perturbation theory. In addition to the Born terms low-lying resonances such as the vector mesons and J P = 1/2 + , 1/2 − baryon resonances are included explicitly and their contributions are calculated. Results for the separated differential cross sections ...
متن کاملThe η ′ and the topological charge density 1
We compare two different frameworks which have been proposed to include the η ′ in chiral perturbation theory. The equivalence of these two approaches is shown both for the purely mesonic case and in the presence of the ground state baryon octet. The relation between the different sets of parameters in both Lagrangians is clarified.
متن کاملNon - perturbative chiral approach to K − p → γY reactions
A recently developed nonperturbative chiral approach to describe the S = −1 meson-baryon reactions has been extended to investigate the near threshold K − p → γΛ, γΣ 0 reactions. With the parameters governed by chiral SU(3) symmetry, we show that the predicted branching ratios Γ K − p→γΛ /Γ K − p→all and Γ K − p→γΣ 0 /Γ K − p→all are close to the experimental values. The coupling with the η cha...
متن کاملBaryon Chiral Perturbation Theory in Partially Quenched Large - N c QCD 1
Baryons of lower spin in partially quenched large-Nc QCD are studied with particular emphasis to interpolation between fully unquenched and fully quenched limits. In large Nc limit of partially quenched QCD, we calculate ∆m, the chiral one-loop correction to baryon masses. We find that leading order contribution to ∆m is independent of number of ghost quarks introduced. For finite Nc, ∆m does s...
متن کامل