arXiv:nucl-ex/0105010·v1·Nuclear Experiment
Test of low-energy theorems for p(\vec{gamma},\pi^{0})p in the threshold region
A. Schmidt🇩🇪 · P. Achenbach · J. Ahrens · H.J. Arends · R. Beck · A.M. Bernstein · V. Hejny · M. Kotulla · B. Krusche · V. Kuhr · R. Leukel · I.J.D. MacGregor
Abstract
The photon asymmetry in the reaction p(\vec{\gamma},\pi^{0})p close to threshold has been measured for the first time with the photon spectrometer TAPS using linearly polarized photons from the tagged-photon facility at the Mainz Microtron MAMI. The total and differential cross sections were also measured simultaneously with the photon asymmetry. This allowed determination of the S-wave and all three P-wave amplitudes. The low-energy theorems based on the parameter-free third-order calculations of heavy-baryon chiral perturbation theory for P1 and P2 agree with the experimental values.
Comments: 14 pages Latex including 3 figures and 1 table