Sum rule for the Compton amplitude and implications for the proton–neutron mass difference

Abstract The Cottingham formula expresses the leading contribution of the electromagnetic interaction to the proton-neutron mass difference as an integral over the forward Compton amplitude. Since quarks and gluons reggeize, the dispersive representation of this amplitude requires a subtraction. We...

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Bibliographic Details
Main Authors: J. Gasser, H. Leutwyler, A. Rusetsky
Format: Article
Language:English
Published: SpringerOpen 2020-12-01
Series:European Physical Journal C: Particles and Fields
Online Access:https://doi.org/10.1140/epjc/s10052-020-08615-2