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arXiv · hep-ph/9712507

A polarised QCD condensate: nu p elastic scattering as a probe of U_A(1) dynamics

S. D. Bass
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Abstract

U_A(1) dynamics have the potential to induce a polarised condensate inside a nucleon. The formation of this condensate is related to the realisation of U_A(1) symmetry breaking by tunneling processes such as instantons. If it is present, the polarised condensate induces a term in g_1 which has support only at x=0. Tunneling processes then induce a net transfer of ``spin'' from finite x to x=0. The polarised condensate may be measured by comparing the flavour-singlet axial charges which are extracted from polarised deep inelastic and nu p elastic scattering experiments.

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S. D. Bass. 1998-03-30. A polarised QCD condensate: nu p elastic scattering as a probe of U_A(1) dynamics. https://doi.org/10.1142/s0217732398000851

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