Magnetic moments of spin 1/2 octet baryons are reevaluated in framework of Heavy Baryon Chiral Perturbation Theory (HBChPT). New formulae for the tree-level approximation are proposed. Calculations of one-loop contributions to magnetic moments are performed in terms of the SU(3)_f couplings of octet baryons to Goldstone bosons. It is shown that contributions of the counter terms needed in the fit prove to be large and comparable to the one-loop contributions. It is shown that upon using natural units for the baryon magnetic moments it is possible to somewhat improve the results. Still we see that one-loop corrections without counter terms do not change the main results of the SU(3) symmetry scheme which gives similar fit upon using simple assumptions and only two free parametrs.
Номер документа: 2003-11/724
Авторы: S.B. Yakovlev, V.S. Zamiralov
Email: zamir@depni.npi.msu.su