%0 Journal Article
%T New insights on low energy pi N scattering amplitudes
%A Wang, Y. F.
%A Yao, D. L.
%A Zheng, H. Q.
%J European Physical Journal C
%D 2018
%V 78
%N 7
%I Springer
%@ 1434-6044
%G English
%F Wang_etal2018
%O WOS:000438110400002
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=3653), last updated on Tue, 24 Jul 2018 11:03:31 +0000
%X The S- and P- wave phase shifts of low-energy pion-nucleon scatterings are analysed using Peking University representation, in which they are decomposed into various terms contributing either from poles or branch cuts. We estimate the left-hand cut contributions with the help of tree-level perturbative amplitudes derived in relativistic baryon chiral perturbation theory up to O(p(2)). It is found that in S-11 and P-11 channels, contributions from known resonances and cuts are far from enough to saturate experimental phase shift data – strongly indicating contributions from low lying poles undiscovered before, and we fully explore possible physics behind. On the other side, no serious disagreements are observed in the other channels.
%R 10.1140/epjc/s10052-018-6024-5
%U http://arxiv.org/abs/1712.09257
%U https://doi.org/10.1140/epjc/s10052-018-6024-5
%P 543 - 18pp