Low energy analyzing powers in pion–proton elastic scattering

• Published in: Physics letters. B Vol. 588; no. 3-4; pp. 155 - 162
• Main Authors: Meier, R., Cröni, M., Bilger, R., van den Brandt, B., Breitschopf, J., Clement, H., Comfort, J.R., Denz, H., Erhardt, A., Föhl, K., Friedman, E., Gräter, J., Hautle, P., Hofman, G.J., Konter, J.A., Mango, S., Pätzold, J., Pavan, M.M., Wagner, G.J., von Wrochem, F.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 27.05.2004; Elsevier Science
• Subjects: Active polarized target; Exact sciences and technology; Hadron-induced low- and intermediate-energy reactions and scattering (energy ≤ 10 gev); Nuclear physics; Nuclear reactions: general; Physics; Pion-baryon interactions; Pion–proton scattering; Polarization phenomena in reactions; Sigma term; Specific reactions and phenomenology; The physics of elementary particles and fields; 24.70.+s; 13.75.Gx; Active polarized target; 25.80.Dj; Pion–proton scattering; Sigma term; Polarization; Pions; Elastic scattering; Pion-proton scattering; Angular distribution; Phase analysis; Kinetic energy
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2004.02.071

Analyzing powers of pion–proton elastic scattering have been measured at PSI with the Low Energy Pion Spectrometer LEPS and 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 π+p scattering, and at 67.3 and 87.2 MeV for π−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.