Updated analysis of $\pi$N elastic scattering data to 2.1~GeV: The Baryon Spectrum

Abstract

We present the results of energy-dependent and single-energy partial-wave analyses of $\pi$N elastic scattering data with laboratory kinetic energies below 2.1~GeV. Resonance structures have been extracted using Breit-Wigner fits, speed plots, and a complex plane mapping of the associated poles and zeroes. This is the first set of resonance parameters from a VPI analysis constrained by fixed-t dispersion relations. We have searched our solutions for structures which may have been missed in our previous analyses, finding candidates in the $S_{11}$ and $F_{15}$ partial-wave amplitudes. Our results are compared with those found by the Karlsruhe, Carnegie-Mellon$-$Berkeley, and Kent State groups.Comment: 25 pages of text plus 5 figures. Revtex file and postscript figures available via anonymous FTP at ftp://clsaid.phys.vt.edu/pub/pi