Physical Review C
We present the first measurement of the reaction 𝛾p -> a₂(1320)⁰ p in the photon energy range 3.5-5.5 GeV and four-momentum transfer squared 0.2 < -t < 2.0 GeV2. Data were collected with the CEBAF Large Acceptance Spectrometer detector at the Thomas Jefferson National Accelerator Facility. The a2resonance was detected by measuring the reaction 𝛾p → π0ηp and reconstructing the π0η invariant mass. The most prominent feature of the differential cross section is a dip at -t ≈ 0.55 GeV2. This can be described in the framework of Regge phenomenology, where the exchange degeneracy hypothesis predicts a zero in the reaction amplitude for this value of the four-momentum transfer.
Original Publication Citation
Celentano, A., Battaglieri, M., De Vita, ... Zachariou, N., Zhang, J., Zhao, Z. W., et al. CLAS Collaboration (2020). First measurement of direct photoproduction of the a₂(1320)⁰ meson on the proton. Physical Review C, 102(3), 7 pp., Article 032201. https://doi.org/10.1103/PhysRevC.102.032201
Adhikari, K.P.; Amaryan, M. J.; Bullumulla, D.; Hauenstein, F.; Khachatryan, M.; Prok, Y.; et al.; and CLAS Collaboration, "First Measurement of Direct Photoproduction of the a2(1320)⁰ Meson on the Proton" (2020). Physics Faculty Publications. 453.