Beam-helicity asymmetries in double-pion photoproduction off the proton

D. Krambrich, F. Zehr, A. Fix, L. Roca, P. Aguar, J. Ahrens, J. R.M. Annand, H. J. Arends, R. Beck, V. Bekrenev, B. Boillat, A. Braghieri, D. Branford, W. J. Briscoe, J. Brudvik, S. Cherepnya, R. Codling, E. J. Downie, P. Dexler, D. I. GlazierP. Grabmayr, R. Gregor, E. Heid, D. Hornidge, O. Jahn, V. L. Kashevarov, A. Knezevic, R. Kondratiev, M. Korolija, M. Kotulla, B. Krusche, A. Kulbardis, M. Lang, V. Lisin, K. Livingston, S. Lugert, I. J.D. MacGregor, D. M. Manley, M. Martinez, J. C. McGeorge, D. Mekterovic, V. Metag, B. M.K. Nefkens, A. Nikolaev, P. Pedroni, F. Pheron, A. Polonski, S. N. Prakhov, J. W. Price, G. Rosner, M. Rost, T. Rostomyan, S. Schumann, D. Sober, A. Starostin, I. Supek, C. M. Tarbert, A. Thomas, M. Unverzagt, Th Walcher, D. P. Watts

Research output: Contribution to journalArticlepeer-review

35 Citations (Scopus)


Beam-helicity asymmetries have been measured at the MAMI accelerator in Mainz in the three isospin channels γ→p→π+π0n, γ→p→π0π0p, and γ→p→π+π-p. The circularly polarized photons, produced from bremsstrahlung of longitudinally polarized electrons, were tagged with the Glasgow magnetic spectrometer. Charged pions and the decay photons of π0 mesons were detected in a 4π electromagnetic calorimeter which combined the Crystal Ball detector with the TAPS detector. The precisely measured asymmetries are very sensitive to details of the production processes and are thus key observables in the modeling of the reaction dynamics.

Original languageEnglish
Article number052002
JournalPhysical Review Letters
Issue number5
Publication statusPublished - 6 Aug 2009

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Beam-helicity asymmetries in double-pion photoproduction off the proton'. Together they form a unique fingerprint.

Cite this