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arXiv · 0711.2967

Photo- and Electron-Production of Mesons on Nucleons and Nuclei

E. Oset·M. Döring·D. Strottman·D. Jido·M. Napsuciale·K. Sasaki·C. A. Vaquera-Araujo·M. Kaskulov·E. Hernandez·H. Nagahiro·S. Hirenzaki
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Abstract

In these lectures I will show some results obtained with the chiral unitary approach applied to the photo and electroproduction of mesons. The results for photoproduction of $ηπ^0 p$ and $K^0 π^0 Σ^+$, together with related reactions will be shown, having with common denominator the excitation of the $Δ(1700)$ resonance which is one of those dynamically generated in the chiral unitary approach. Then I will show results obtained for the $e^+ e^- \to ϕf_0(980)$ reaction which reproduce the bulk of the data except for a pronounced peak, giving support to a new mesonic resonance, X(2175). Results will also be shown for the electromagnetic form factors of the $N^*(1535)$ resonance, also dynamically generated in this approach. Finally, I will show some results on the photoproduction of the $ω$ in nuclei, showing that present experimental results claiming a shift of the $ω$ mass in the medium are tied to a particular choice of background and are not conclusive. One the other hand, the same experimental results show unambiguously a huge increase of the $ω$ width in the nuclear medium.

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E. Oset, M. Döring, D. Strottman, D. Jido, M. Napsuciale, K. Sasaki, C. A. Vaquera-Araujo, M. Kaskulov, E. Hernandez, H. Nagahiro, S. Hirenzaki. 2008-02-01. Photo- and Electron-Production of Mesons on Nucleons and Nuclei. https://doi.org/10.1016/j.ppnp.2007.12.024

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