Beam asymmetry Σ measurements of π^{-} photoproduction on neutrons (original) (raw)

Beam asymmetry σ of the π- Photoproduction off neutron

International Journal of Modern Physics E, 2010

The -beam asymmetry in the photoproduction of negative pions on quasi-free neutrons in a deuterium target was measured at the Grenoble Anneau Accelerateur Laser in the energy interval 700-1500 MeV and over a wide angular range, using polarized and tagged photons. Results are compared with recent partial-wave analyses.

Beam asymmetry Sigma measurements of pi- photoproduction on neutrons

Physical Review C, 2010

The Sigma\SigmaSigma beam asymmetry in the photoproduction of negative pions from quasi-free neutrons in a deuterium target was measured at Graal in the energy interval 700 - 1500 MeV and a wide angular range, using polarized and tagged photons. The results are compared with recent partial wave analyses.

36 Measurement of Σ beam asymmetry in π0 photoproduction off the neutron in the second and third resonances region - The European Physical Journal A, November 2009

Measurement of Σ beam asymmetry in π0 photoproduction off the neutron in the second and third resonances region - The European Physical Journal A, Hadrons and Nuclei, November 2009, Vol. 42, N. 2, pp. 151-157, ISSN: 1434-6001, doi: 10.1140/epja/i2009-10870-x di R. Di Salvo, A. Fantini, G. Mandaglio, F. Mammoliti, O. Bartalini, V. Bellini, J. P. Bocquet, L. Casano, A. D’angelo, J. P. Didelez, D. Franco, G. Gervino, F. Ghio, G. Giardina, B. Girolami, A. Giusa, M. Guidal, E. Hourany, R. Kunne, A. Lapik, P. Levi Sandri, A. Lleres, M. Manganaro, D. Moricciani, A. N. Mushkarenkov, V. Nedorezov, C. Randieri, D. Rebreyend, N. Rudnev, G. Russo, C. Schaerf, M. L. Sperduto, M. C. Sutera, A. Turinge, V. Vegna, A. Fix, S. S. Kamalov, L. Tiator (2009) Abstract The Σ beam asymmetry in the photoproduction of neutral pions from quasi-free nucleons in a deuteron target was measured for the first time between 0.60 and 1.50GeV, with the GRAAL polarized and tagged photon beam. The asymmetry values from the quasi-free proton were found equal to the ones extracted from a pure proton target. The asymmetries from quasi-free proton and quasi-free neutron were found equal up to 0.82GeV and substantially different at higher energies. The results are compared with recent partial-wave analyses.

Measurement of $ \Sigma$ beam asymmetry in $ \pi^{0}_{}$ photoproduction off the neutron in the second and third resonances region⋆

The European Physical Journal A, 2009

The Σ beam asymmetry in the photoproduction of neutral pions from quasi-free nucleons in a deuteron target was measured for the first time between 0.60 and 1.50 GeV, with the GRAAL polarized and tagged photon beam. The asymmetry values from the quasi-free proton were found equal to the ones extracted from a pure proton target. The asymmetries from quasi-free proton and quasi-free neutron were found equal up to 0.82 GeV and substantially different at higher energies. The results are compared with recent partial-wave analyses.

Measurement of beam asymmetry in photoproduction off the neutron in the second and third resonances region ⋆

European Physical Journal A, 2009

The $ \Sigma$ beam asymmetry in the photoproduction of neutral pions from quasi-free nucleons in a deuteron target was measured for the first time between 0.60 and 1.50GeV, with the GRAAL polarized and tagged photon beam. The asymmetry values from the quasi-free proton were found equal to the ones extracted from a pure proton target. The asymmetries from quasi-free proton and quasi-free neutron were found equal up to 0.82GeV and substantially different at higher energies. The results are compared with recent partial-wave analyses.

43 Beam asymmetry Σ measurements on the π- Photoproduction off neutrons - Physical Review C, October 2010

Beam asymmetry Σ measurements on the π- Photoproduction off neutrons - The American Physical Society, Physical Review C, Nuclear Physics, October 2010, Vol. 82, N. 4, pp. 045209-1-045209-7, ISSN: 0556-2813, doi: 10.1103/PhysRevC.82.045209 di G. Mandaglio, F. Mammoliti, M. Manganaro, V. Bellini, J. P. Bocquet, L. Casano, A. D'Angelo, R. Di Salvo, A. Fantini, D. Franco, G. Gervino, F. Ghio, G. Giardina, B. Girolami, A. Giusa, A. Ignatov, A. Lapik, P. Levi Sandri, A. Lleres, D. Moricciani, A. N. Mushkarenkov, V. Nedorezov, C. Randieri, D. Rebreyend, N. V. Rudnev, G. Russo, C. Schaerf, M. L. Sperduto, M. C. Sutera, A. Turinge, V. Vegna, W. J. Briscoe, I. I. Strakovsky (2010) Abstract The Σ beam asymmetry in the photoproduction of negative pions from quasi-free neutrons in a deuterium target was measured at Graal in the energy interval 700 - 1500 MeV and a wide angular range, using polarized and tagged photons. The results are compared with recent partial wave analyses.

First measurement of the Σ beam asymmetry in η photoproduction on the neutron

Physical Review C, 2008

The Σ beam asymmetry in the photoproduction of negative pions from quasi-free neutrons in a deuterium target was measured at Graal in the energy interval 700 -1500 MeV and a wide angular range, using polarized and tagged photons. The results are compared with recent partial wave analyses.

42 Beam Asymmetry Σ of the π- Photoproduction off Neutron - International Journal of Modern Physics E, June 2010

Beam Asymmetry Σ of the π- Photoproduction off Neutron - International Journal of Modern Physics E, June 2010, Vol. 19, N. 5-6, pp. 965-976, doi: 10.1142/S0218301310015412 di G. Mandaglio, V. Bellini, J. P. Bocquet, L. Casano, A. D'Angelo, R. Di Salvo, A. Fantini, D. Franco, G. Gervino, F. Ghio, G. Giardina, B. Girolami, A. Giusa, A. S. Ignatov, A. M. Lapik, P. Levi Sandri, A. Lleres, F. Mammoliti, M. Manganaro, D. Moricciani, A. N. Mushkarenkov, V. G. Nedorezov, C. Randieri, D. Rebreyend, N. V. Rudnev, G. Russo, C. Schaerf, M. L. Sperduto, M. C. Sutera, A. Turinge, V. Vegna (2010) Abstract We present the analysis of data performed in order to identify the events of the γ + n → π- + p reaction obtained by bombarding a liquid Deuterium target with a polarised γ beam of 0.55-1.5 GeV at the Graal-experiment. We show the effect of different kinematic and hardware constraints used to reduce the contamination coming from the concurrent reaction channels. By the simulation we estimate the contamination degree due to the other reaction channels so we can test the reliability of our method. We describe a new three-dimensional cut based on the Fermi momentum reconstruction and its effect on the suppression of the concurrent double charged pion photoproduction. We present the preliminary beam asymmetry Σ of the π- fotoproduction off quasi-free neutron up to about θc.m., π- = 165° together with some theoretical multipolar analysis. For a comparison we also report the data present in literature on the same reaction for Eγ =850-1740 MeV and θc.m., π- ≤105°.

Precise measurement of Σ beam asymmetry for positive pion photoproduction on the proton from 800 to 1500 MeV

Physics Letters B, 2002

The Σ beam asymmetry for positive pion photoproduction on the proton has been measured over an angular range of 40-170 • at photon energies from 0.8 to 1.5 GeV. The resulting data set includes 237 accurate points, 136 of these belonging to an almost unexplored domain above 1.05 GeV. Data of such high precision provide severe constraints for partial wave analyses. The influence of this experiment on the GW multipole analysis is demonstrated. Significant changes are found in multipoles connected to the S 31 (1620) and P 13 (1720) resonances. Comparisons using the MAID analysis are also presented. 0370-2693/02/$ -see front matter  2002 Published by Elsevier Science B.V. PII: S 0 3 7 0 -2 6 9 3 ( 0 2 ) 0 2 4 6 7 -X GRAAL Collaboration, GW-SAID Group / Physics Letters B 544 (2002) 113-120  2002 Published by Elsevier Science B.V.

Precise measurement of Σ beam asymmetry for positive pion photoproduction on the proton from 550 to 1100 MeV

Physics Letters B, 2000

S beam asymmetries for p q photoproduction on the proton have been measured in the energy range 550-1100 MeV over a wide angular range. The statistical and systematic errors of the data are much lower than in previous measurements, due to the high polarization of the photon beam and the cylindrical geometry of the 4p detector. Our results confirm the 1 E-mail address: Capogni@ginevra.roma2.infn.it 2 E-mail address: Slava@cpc.inr.ac.ru, Slava@gravax2.in2p3.fr 0370-2693r00r$ -see front matter q 2000 Elsevier Science B.V. All rights reserved.