Witthauer, L., Dieterle, M., Abt, S. et al. (82 more authors) (2016) Insight into the Narrow Structure in η Photoproduction on the Neutron from Helicity-Dependent Cross Sections. Physical Review Letters. 132502. ISSN: 1079-7114
Abstract
The double polarization observable E and the helicity dependent cross sections σ1/2 and σ3/2 were measured for η photoproduction from quasifree protons and neutrons. The circularly polarized tagged photon beam of the A2 experiment at the Mainz MAMI accelerator was used in combination with a longitudinally polarized deuterated butanol target. The almost 4π detector setup of the Crystal Ball and TAPS is ideally suited to detect the recoil nucleons and the decay photons from η→2γ and η→3π0. The results show that the narrow structure previously observed in η photoproduction from the neutron is only apparent in σ1/2 and hence, most likely related to a spin-1/2 amplitude. Nucleon resonances that contribute to this partial wave in η production are only N 1/2- (S11) and N 1/2+ (P11). Furthermore, the extracted Legendre coefficients of the angular distributions for σ1/2 are in good agreement with recent reaction model predictions assuming a narrow resonance in the P11 wave as the origin of this structure.
Metadata
| Item Type: | Article |
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| Authors/Creators: |
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| Copyright, Publisher and Additional Information: | © 2016 American Physical Society |
| Dates: |
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| Institution: | The University of York |
| Academic Units: | The University of York > Faculty of Sciences (York) > Physics (York) |
| Depositing User: | Pure (York) |
| Date Deposited: | 17 Sep 2018 11:30 |
| Last Modified: | 17 Sep 2025 01:05 |
| Published Version: | https://doi.org/10.1103/PhysRevLett.117.132502 |
| Status: | Published |
| Refereed: | Yes |
| Identification Number: | 10.1103/PhysRevLett.117.132502 |
| Related URLs: | |
| Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:135801 |

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