Double-polarization observable G in neutral-pion photoproduction off the proton
Abstract
This paper reports on a measurement of the double-polarization observable G in photoproduction off the proton using the CBELSA/TAPS experiment at the ELSA accelerator in Bonn. The observable G is determined from reactions of linearly-polarized photons with longitudinally-polarized protons. The polarized photons are produced by bremsstrahlung off a properly oriented diamond radiator. A frozen spin butanol target provides the polarized protons. The data cover the photon energy range from 617 to 1325 MeV and a wide angular range. The experimental results for G are compared to predictions by the Bonn-Gatchina (BnGa), J\"ulich-Bonn (J\"uBo), MAID and SAID partial wave analyses. Implications of the new data for the pion photoproduction multipoles are discussed.
Keywords
Cite
@article{arxiv.1604.02922,
title = {Double-polarization observable G in neutral-pion photoproduction off the proton},
author = {A. Thiel and H. Eberhardt and M. Lang and F. Afzal and A. V. Anisovich and B. Bantes and D. Bayadilov and R. Beck and M. Bichow and K. -T. Brinkmann and S. Böse and V. Crede and M. Dieterle and H. Dutz and D. Elsner and R. Ewald and K. Fornet-Ponse and St. Friedrich and F. Frommberger and Ch. Funke and St. Goertz and M. Gottschall and A. Gridnev and M. Grüner and E. Gutz and D. Hammann and Ch. Hammann and J. Hannappel and J. Hartmann and W. Hillert and Ph. Hoffmeister and Ch. Honisch and T. Jude and D. Kaiser and H. Kalinowsky and F. Kalischewski and S. Kammer and I. Keshelashvili and P. Klassen and V. Kleber and F. Klein and E. Klempt and K. Koop and B. Krusche and M. Kube and I. Lopatin and Ph. Mahlberg and K. Makonyi and V. Metag and W. Meyer and J. Müller and J. Müllers and M. Nanova and V. Nikonov and D. Piontek and S. Reeve and G. Reicherz and S. Runkel and A. Sarantsev and Ch. Schmidt and H. Schmieden and T. Seifen and V. Sokhoyan and K. Spieker and U. Thoma and M. Urban and H. van Pee and D. Walther and Ch. Wendel and A. Wilson and A. Winnebeck and L. Witthauer},
journal= {arXiv preprint arXiv:1604.02922},
year = {2017}
}