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Dutz H, Helbing K, Krimmer J, Speckner T, Zeitler G, Ahrens J, Altieri S, Annand JRM, Anton G, Arends HJ, Beck R, Bock A, Bradtke C, Braghieri A, v Drachenfels W, Frommberger F, Godo M, Goertz S, Grabmayr P, Hasegawa S, Hansen K, Harmsen J, Heid E, Hillert W, Holvoet H, Horikawa N, Iwata T, Van Hoorebeke L, d'Hose N, Jennewein P, Kiel B, Klein F, Kondratiev R, Lang M, Lannoy B, Leukel R, Lisin V, Menze D, Meyer W, Michel T, Naumann J, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E, Reicherz G, Rohlof C, Rostomyan T, Sauer M, Schoch B, Schumacher M, Tamas G, Thomas A, van de Vyver R, Weihofen W, Zapadtka F. Measurement of helicity-dependent photoabsorption cross sections on the neutron from 815 to 1825 MeV. Phys Rev Lett 2005; 94:162001. [PMID: 15904214 DOI: 10.1103/physrevlett.94.162001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Indexed: 05/02/2023]
Abstract
Helicity-dependent total photoabsorption cross sections on the deuteron have been measured for the first time at ELSA (Bonn) in the photon energy range from 815 to 1825 MeV. Circularly polarized tagged photons impinging on a longitudinally polarized LiD target have been used together with a highly efficient 4pi detector system. The data around 1 GeV are not compatible with predictions from existing multipole analyses. From the measured energy range an experimental contribution to the GDH integral on the neutron of [33.9 +/- 5.5(stat) +/- 4.5(syst)] microb is extracted.
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Affiliation(s)
- H Dutz
- Physikalisches Institut, Universität Bonn, D-53115 Bonn, Germany
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Dutz H, Helbing K, Krimmer J, Speckner T, Zeitler G, Ahrens J, Altieri S, Annand JRM, Anton G, Arends HJ, Beck R, Bock A, Bradtke C, Braghieri A, v Drachenfels W, Frommberger F, Godo M, Goertz S, Grabmayr P, Hasegawa S, Hansen K, Harmsen J, Heid E, Hillert W, Holvoet H, Horikawa N, Iwata T, Hoorebeke LV, D'Hose N, Jennewein P, Kiel B, Klein F, Kondratiev R, Lang M, Lannoy B, Leukel R, Lisin V, Menze D, Meyer W, Michel T, Naumann J, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E, Reicherz G, Rohlof C, Rostomyan T, Sauer M, Schoch B, Schumacher M, Tamas G, Thomas A, van de Vyver R, Weihofen W, Zapadtka F. Experimental check of the Gerasimov-Drell-Hearn sum rule for 1H. Phys Rev Lett 2004; 93:032003. [PMID: 15323817 DOI: 10.1103/physrevlett.93.032003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2004] [Indexed: 05/24/2023]
Abstract
For the first time we checked the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the proton experimentally in the photon energy range from 0.2-2.9 GeV with the tagged photon facilities at MAMI (Mainz) and ELSA (Bonn). New data of the doubly polarized total cross section difference are presented in the energy range from 1.6 to 2.9 GeV. The contribution to the GDH integral from 0.2-2.9 GeV yields [254+/-5(stat)+/-12(syst)] microb with negative contributions in the Regge regime at photon energies above 2.1 GeV. This trend supports the validity of the GDH sum rule.
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Affiliation(s)
- H Dutz
- Physikalisches Institut, Universität Bonn, D-53115 Bonn, Germany
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Dutz H, Helbing K, Krimmer J, Speckner T, Zeitler G, Ahrens J, Altieri S, Annand JRM, Anton G, Arends HJ, Beck R, Bock A, Bradtke C, Braghieri A, v Drachenfels W, Frommberger F, Godo M, Goertz S, Grabmayr P, Hasegawa S, Hansen K, Harmsen J, Heid E, Hillert W, Holvoet H, Horikawa N, Iwata T, Van Hoorebeke L, d'Hose N, Jennewein P, Kiel B, Klein F, Kondratiev R, Lang M, Lannoy B, Leukel R, Lisin V, Menze D, Meyer W, Michel T, Naumann J, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E, Reicherz G, Rohlof C, Rostomyan T, Sauer M, Schoch B, Schumacher M, Tamas G, Thomas A, van de Vyver R, Weihofen W, Zapadtka F. First Measurement of the Gerasimov-Drell-Hearn Sum Rule for 1H from 0.7 to 1.8 GeV at ELSA. Phys Rev Lett 2003; 91:192001. [PMID: 14611575 DOI: 10.1103/physrevlett.91.192001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2003] [Indexed: 05/24/2023]
Abstract
To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out with a 4pi detection system, a circularly polarized tagged photon beam, and a frozen spin polarized proton target. The contribution to the GDH sum rule in this photon energy range is [49.9+/-2.4(stat)+/-2.2(syst)] microb.
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Affiliation(s)
- H Dutz
- Physikalisches Institut, Universität Bonn, D-53115 Bonn, Germany
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