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arXiv · hep-ph/9305320

A Dynamical Resolution of the Sigma Term Puzzle

Richard D. Ball·Stefano Forte·Jason Tigg
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Abstract

We propose a resolution of the puzzle posed by the discrepancy between the pion-nucleon sigma term inferred from pion-nucleon scattering, and that deduced from baryon mass splittings using the Zweig rule. We show that there is a significant hypercharge-dependent dynamical contribution to baryon masses, not hitherto included in the analysis, which may be estimated using the scale Ward identity, and computed by solution of the Schwinger-Dyson equation for the quark self-energy. We find that the discrepancy is completely resolved without the need for any Zweig rule violation.

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Richard D. Ball, Stefano Forte, Jason Tigg. 1993-05-26. A Dynamical Resolution of the Sigma Term Puzzle. https://doi.org/10.1016/0550-3213(94)90210-0

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