Baryon masses in a loop expansion with a form factor

Journal Article · Thu Apr 01 04:00:00 EST 1999 · Physical Review, D

DOI:https://doi.org/10.1103/PhysRevD.59.076001· OSTI ID:328598

Ha, P; Durand, L ^[1]

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1. Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

We show that the average multiplet masses in the baryon octet and decuplet can be fitted with an average error of only 0.5{plus_minus}0.3; MeV in a meson loop expansion with chiral SU(6) couplings, with the hadrons treated as composite particles using a baryon-meson form factor. The form factor suppresses unphysical short distance effects and leads to a controllable expansion. We find, in contrast to the results of standard chiral perturbation theory, that pion loops are as important as kaon or eta loops as would be expected when only intermediate- and long-distance contributions are retained. We also find that the contributions of decuplet intermediate states are important in the calculation of the masses, and those states must be included explicitly in a consistent theory. These results agree with those of our recent loop-expansion analysis of the baryon magnetic moments. We show, finally, that the parts of the loop contributions that change the tree-level structure of the baryon masses are small, but largely account for the violations of the baryon mass sum rules which hold at the tree level. thinsp {copyright} {ital 1999} {ital The American Physical Society}

• OSTI ID: 328598
• Journal Information: Physical Review, D, Journal Name: Physical Review, D Journal Issue: 7 Vol. 59; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BARYONS
CHIRAL SYMMETRY
ETA MESONS
FORM FACTORS
KAONS
MESONS
PERTURBATION THEORY
PIONS
REST MASS
SU-6 GROUPS
SUM RULES