Quasi-free photoproduction of η-mesons off 3He nuclei

Witthauer, L. et al. (2013) Quasi-free photoproduction of η-mesons off 3He nuclei. European Physical Journal A, 49(154), (doi:10.1140/epja/i2013-13154-0)

[img]
Preview
Text
89384 (1).pdf - Cover Image

82kB
[img]
Preview
Text
89384.pdf - Published Version
Available under License Creative Commons Attribution Share Alike.

2MB

Abstract

Quasi-free photoproduction of η-mesons has been measured off nucleons bound in 3He nuclei for incident photon energies from the threshold region up to 1.4 GeV. The experiment was performed at the tagged photon facility of the Mainz MAMI accelerator with an almost 4π covering electromagnetic calorimeter, combining the TAPS and Crystal Ball detectors. The η-mesons were detected in coincidence with the recoil nucleons. This allowed a comparison of the production cross section off quasi-free protons and quasi-free neutrons and a full kinematic reconstruction of the final state, eliminating effects from nuclear Fermi motion. In the S11(1535) resonance peak, the data agree with the neutron/proton cross section ratio extracted from measurements with deuteron targets. More importantly, the prominent structure observed in photoproduction off quasi-free neutrons bound in the deuteron is also clearly observed. Its parameters (width, strength) are consistent with the expectations from the deuteron results. On an absolute scale the cross sections for both quasi-free protons and neutrons are suppressed with respect to the deuteron target pointing to significant nuclear final-state interaction effects.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:McGeorge, Dr John and Robinson, Mr Jamie and Downie, Dr Evangeline and Livingston, Dr Kenneth and MacGregor, Professor I and Howdle, Mr David and Annand, Dr John and Hamilton, Dr David and Glazier, Dr Derek and Rosner, Professor Guenther
Authors: Witthauer, L., Werthmüller, D., Keshelashvili, I., Aguar-Bartolomé, P., Ahrens, J., Annand, J.R.M., Arends, H.J., Bantawa, K., Beck, R., Bekrenev, V., Braghieri, A., Branford, D., Briscoe, W.J., Brudvik, J., Cherepnya, S., Demissie, B., Dieterle, M., Downie, E.J., Drexler, P., Fil’kov, L.V., Fix, A., Glazier, D.I., Hamilton, D., Heid, E., Hornidge, D., Howdle, D., Huber, G.M., Jaegle, I., Jahn, O., Jude, T.C., Käser, A., Kashevarov, V.L., Kondratiev, R., Korolija, M., Kruglov, S.P., Krusche, B., Kulbardis, A., Lisin, V., Livingston, K., MacGregor, I.J.D., Maghrbi, Y., Mancell, J., Manley, D.M., Marinides, Z., Martinez, M., McGeorge, J.C., McNicoll, E., Metag, V., Middleton, D.G., Mushkarenkov, A., Nefkens, B.M.K., Nikolaev, A., Novotny, R., Oberle, M., Ostrick, M., Oussena, B., Pedroni, P., Pheron, F., Polonski, A., Prakhov, S., Robinson, J., Rosner, G., Rost, M., Rostomyan, T., Schumann, S., Sikora, M.H., Sober, D., Starostin, A., Supek, I., Thiel, M., Thomas, A., Unverzagt, M., and Watts, D.P.
College/School:College of Science and Engineering > School of Physics and Astronomy
Journal Name:European Physical Journal A
Publisher:Springer
ISSN:1434-6001
ISSN (Online):1434-601X
Copyright Holders:Copyright © 2013 The Authors
First Published:First published in European Physical Journal A 49:154
Publisher Policy:Reproduced under a Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
570711Nuclear Physics GroupDavid IrelandScience & Technologies Facilities Council (STFC)ST/J000175/1P&A - PHYSICS & ASTRONOMY