TY  - JOUR
AU  - Wang, Y. F.
AU  - Yao, D. L.
AU  - Zheng, H. Q.
PY  - 2019
DA  - 2019//
TI  - New insights on low energy pi N scattering amplitudes: comprehensive analyses at O (p(3)) level
T2  - Chin. Phys. C
JO  - Chinese Physics C
SP  - 064110
EP  - 22pp
VL  - 43
IS  - 6
PB  - Iop Publishing Ltd
KW  - dispersion relations
KW  - pion-nucleon scattering
KW  - chiral perturbation theory
AB  - A production representation of partial-wave S matrix is utilized to construct low-energy elastic pion-nucleon scattering amplitudes from cuts and poles on complex Riemann sheets. Among them, the contribution of left-hand cuts is estimated using the O (p(3)) results obtained in covariant baryon chiral perturbation theory within the extendedon-nass-shell scheme. By fitting to data on partial-wave phase shifts, it is indicated that the existences of hidden poles in S-11 and P-11 channels, as conjectured in our previous paper [Eur. Phys. J. C, 78(7): 543 (2018)], are firmly established. Specifically, the pole mass of the S-11 hidden resonance is determined to be (895 +/- 81)-(164 +/- 23)i MeV, whereas, the virtual pole in the P-11 channel locates at (966 +/- 18) MeV. It is found that analyses at the O (p(3)) level improves significantly the fit quality, comparing with the previous O (p(2)) one. Quantitative studies with cautious physical discussions are also conducted for the other S- and P-wave channels.
SN  - 1674-1137
UR  - https://arxiv.org/abs/1811.09748
UR  - https://doi.org/10.1088/1674-1137/43/6/064110
DO  - 10.1088/1674-1137/43/6/064110
LA  - English
N1  - WOS:000468501700013
ID  - Wang_etal2019
ER  -