{Delta} isobar masses, large N{sub c} relations, and the quark model
- Department of Physics and Supercomputer Computations Research Institute, Florida State University, Tallahassee, Florida 32306 (United States)
- Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States)
Motivated by recent remarks on the {Delta}{sup +} mass and comparisons between the quark model and relations based on large-N{sub c} with perturbative flavor breaking, two sets of {Delta} masses consistent with these constraints are constructed. These two sets, based either on an experimentally determined mass splitting or a quark model of isospin symmetry breaking, are shown to be inconsistent. The model dependence of this inconsistency is examined, and suggestions for improved experiments are made. An explicit quark model calculation and mass relations based on the large-N{sub c} limit with perturbative flavor breaking are compared. The expected level of accuracy of such relations is realized in the quark model, except for mass relations derived by combining others which correspond to different SU(6) representations. It is shown that the {Delta}{sup 0} and {Delta}{sup ++} pole masses and {Delta}{sup 0}{minus}{Delta}{sup +}=({Delta}{sup {minus}}{minus}{Delta}{sup ++})/3{approx_equal}1.5thinspMeV are more consistent with model expectations than the analogous Breit-Wigner masses and their splittings. {copyright} {ital 1998} {ital The American Physical Society}
- OSTI ID:
- 289058
- Journal Information:
- Physical Review, D, Vol. 59, Issue 1; Other Information: PBD: Jan 1999
- Country of Publication:
- United States
- Language:
- English
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