arXiv subjects

Martin Mojzis

Publications and source records attributed to Martin Mojzis.

5 recordsLinked to original sources

arXiv2000

The chiral effective pion-nucleon Lagrangian of order p^4

We construct the minimal effective chiral pion-nucleon SU(2) Lagrangian at fourth order in the chiral expansion. The Lagrangian contains 118 in principle measurable terms. We develop both the relativistic as well as the heavy baryon formulation of the effective field theory. For the latter, we also work out explicitly all 1/m corrections at fourth order. We display all relevant relations needed to find the linearly independent terms.

hep-ph↗

arXiv2000

Field Redefinitions and Wave Function Renormalization to $O(p^4)$ in Heavy Baryon Chiral Perturbation Theory

Mass- and wave-function renormalization is calculated to order $p^4$ in heavy baryon chiral perturbation theory. Two different schemes used in the literature are considered. Several technical issues like field redefinitions, non-transformation of sources as well as subtleties related to the definition of the baryon propagator are discussed. The nucleon axial-vector coupling constant $g_A$ is calculated to order $p^4$ as an illustrative example.

hep-ph↗

arXiv2000

Reordering of Baryon Chiral Perturbation Theory

Reordering of the chiral perturbation series, proposed recently by Becher and Leutwyler in the framework of SU(2) baryonic ChPT, is applied to the SU(3) case. This results in improved convergence of the chiral expansion of static properties of the lowest lying baryon octet, which in most cases is quite impressive. Finite renormalization of coupling constants and the role it plays in the interpretation of effective field theories is discussed. Some future tests of the viability of the scheme are proposed too.

hep-ph↗

arXiv1997

Elastic pion-nucleon Scattering to O(p^3) in Heavy Baryon Chiral Perturbation Theory

The elastic pi-N scattering amplitude in the isospin limit is calculated in the framework of heavy baryon chiral perturbation theory, up to the third order. Threshold parameters like scattering lengths, volumes, effective ranges, etc. are compared with data. All relevant low energy constants are fixed from the available pion-nucleon data. A clear improvement in the description of data is observed, when going from the first two orders in the chiral expansion to the third one. The importance of even higher orders is suggested by the result.

hep-ph↗

arXiv1995

Low-energy expansion of the pion-nucleon Lagrangian

The renormalized pion-nucleon Lagrangian is calculated to O(p^3) in heavy baryon chiral perturbation theory. By suitably chosen transformations of the nucleon field, the Lagrangian is brought to a standard form.

hep-ph↗