Original scientific paper

Long distance effects and strangeness in the nucleon

John F. Donoghue ; Department of Physics-LGRT, University of Massachusetts, Amherst, MA 01003
Barry R. Holstein ; Department of Physics-LGRT, University of Massachusetts, Amherst, MA 01003
Tobias Huber ; Department of Physics-LGRT, University of Massachusetts, Amherst, MA 01003; Institut für Theoretische Teilchenphysik, Universität Karlsruhe, Karlsruhe, Germany; Institut für Theoretische Physik, Universität Zürich, Zürich, Switzerland
Andreas Ross ; Department of Physics-LGRT, University of Massachusetts, Amherst, MA 01003; Institut für Theoretische Teilchenphysik, Universität Karlsruhe, Karlsruhe, Germany

Abstract

We discuss the calculation of the strange magnetic radius of the proton in chiral perturbation theory. In particular, we investigate the low-energy component of the loop integrals involving kaons. We separate the chiral calculation into a low-energy part and a high-energy component through use of a momentum space separation scale. This separation shows that most of the chiral calculation comes from high energies where the effective field theory treatment is not valid. The resulting lowenergy prediction is in better agreement with dispersive treatments. Finally, we briefly discuss magnetic moments and show how our techniques can help resolve an old puzzle in understanding the magnetic moments of the proton and Σ+.

Keywords

magnetic moments; proton; Σ+; strange magnetic radius; chiral perturbation theory

Hrčak ID:

304090

URI

https://hrcak.srce.hr/304090

Publication date:

1.6.2005.

Article data in other languages: croatian

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