Eur. Phys. J. A 11, 441-455 (2001)

Photoproduction of positive pions from hydrogen at large angles in the energy range 0.3-2.0 GeV

H.W. Dannhausen, E.J. Durwen, H.M. Fischer, M. Leneke, W. Niehaus and F. Takasaki

Physikalisches Institut, Universität Bonn, D-53115 Bonn, Germany

fischer@physik.uni-bonn.de

(Received: 2 February 2000 / Revised version: 16 July 2001 Communicated by Th. Walcher)

Abstract
The differential cross-section for the reaction was measured using the bremsstrahlung beam of the Bonn 2.5 GeV electron synchrotron. The pions were detected and momentum analysed in a multichannel magnet spectrometer. Data reduction resulted in 1278 measured cross-sections which are presented as energy distributions at six laboratory angles between 180° and 95°. The range of laboratory photon energies extended from 0.3 to 2.1 GeV. The statistical accuracy is better than 3 percent, the systematic error is about 5 percent. The data are compared with other experimental results and predictions of a phenomenological analysis. These cross-sections are the result of a measurement program which was started in the seventies. Further results will be reported in forthcoming publications.

PACS
13.60.Le - Meson production.
25.20.Lj - Photoproduction reactions.

© Società Italiana di Fisica, Springer-Verlag 2001