Analyzing powers of pion-proton elastic scattering have been measured at PSI with the Low Energy Pion Spectrometer LEPS as well as a novel polarized scintillator target. Angular distributions between 40 and 120 deg (c.m.) were taken at 45.2, 51.2, 57.2, 68.5, 77.2, and 87.2 MeV incoming pion kinetic energy for pi+ p scattering, and at 67.3 and 87.2 MeV for pi- p scattering. These new measurements constitute a substantial extension of the polarization data base at low energies. Predictions from phase shift analyses are compared with the experimental results, and deviations are observed at low energies.
@article{arxiv.nucl-ex/0402018,
title = {Low Energy Analyzing Powers in Pion-Proton Elastic Scattering},
author = {R. Meier and M. Cröni and R. Bilger and B. van den Brandt and J. Breitschopf and H. Clement and J. R. Comfort and H. Denz and A. Erhardt and K. Föhl and E. Friedman and J. Gräter and P. Hautle and G. J. Hofman and J. A. Konter and S. Mango and J. Pätzold and M. M. Pavan and G. J. Wagner and F. von Wrochem},
journal= {arXiv preprint arXiv:nucl-ex/0402018},
year = {2008}
}