8 v 1 1 5 A pr 1 99 7 Color Anomaly and Flavor - Singlet Axial Charge of the Proton in the Chiral Bag : The Cheshire Cat Revisited
نویسندگان
چکیده
Quantum effects inside the chiral bag induce a color anomaly which requires a compensating surface term to prevent breakdown of color gauge invariance. We show that the presence of this surface term first discovered several years ago allows one to derive in a gauge-invariant way a chiral-bag version of the Shore-Veneziano two-component formula for the flavor-singlet axial charge of the proton. This has relevance to what is referred to as the " proton spin problem " on the one hand and to the Cheshire-Cat phenomenon in hadron structure on the other. We show that when calculated to the leading order in the color gauge coupling and for a specific color electric monopole configuration in the bag , one can obtain a striking Cheshire-Cat phenomenon with a negligibly small singlet axial charge .
منابع مشابه
The Cheshire Cat Revisited
The concept of effective field theory leads in a natural way to a construction principle for phenomenological sensible models known under the name of the Cheshire Cat Principle. We review its formulation in the chiral bag scenario and discuss its realization for the flavor singlet axial charge. Quantum effects inside the chiral bag induce a color anomaly which requires a compensating surface te...
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