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arXiv · 1702.02065

Antinucleon-nucleon interaction at next-to-next-to-next-to-leading order in chiral effective field theory

Ling-Yun Dai·Johann Haidenbauer·Ulf-G. Meißner
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Abstract

Results for the antinucleon-nucleon ($\bar NN$) interaction obtained at next-to-next-to-next-to-leading order in chiral effective field theory (EFT) are reported. A new local regularization scheme is used for the pion-exchange contributions that has been recently suggested and applied in a pertinent study of the $NN$ force within chiral EFT. Furthermore, an alternative strategy for estimating the uncertainty is utilized that no longer depends on a variation of the cutoffs. The low-energy constants associated with the arising contact terms are fixed by a fit to the phase shifts and inelasticities provided by a phase-shift analysis of $\bar pp$ scattering data. An excellent description of the $\bar NN$ amplitudes is achieved at the highest order considered. Moreover, because of the quantitative reproduction of partial waves up to $J=3$, there is also a nice agreement on the level of $\bar pp$ observables. Specifically, total and integrated elastic and charge-exchange cross sections agree well with the results from the partial-wave analysis up to laboratory energies of $300$ MeV, while differential cross sections and analyzing powers are described quantitatively up to $200$-$250$ MeV. The low-energy structure of the $\bar NN$ amplitudes is also considered and compared to data from antiprotonic hydrogen.

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Ling-Yun Dai, Johann Haidenbauer, Ulf-G. Meißner. 2017-02-07. Antinucleon-nucleon interaction at next-to-next-to-next-to-leading order in chiral effective field theory. https://doi.org/10.1007/jhep07(2017)078

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