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arXiv · 1910.02690

Diphoton elastic scattering in UPC at smaller $W_{\gamma\gamma}$

Antoni Szczurek
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Abstract

We present a study of photon-photon scattering for $W_{\gamma\gamma} < 5$ GeV. We extend earlier calculations of this cross section for $W_{\gamma\gamma}>$ 5 GeV into the low mass range where photoproduction of the pseudoscalar mesons $\eta$(548), $\eta^{'}(958)$ and other mesonic resonances contribute to the two-photon final states. We consider the dominant background of the two photon final state which arises from $\gamma \gamma$ decays of photoproduced $\pi^{0} \pi^0$-pairs. We discuss how to reduce the background by imposing cuts on different kinematical variables. We present results for ALICE and LHCb kinematics.

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Antoni Szczurek. 2019-10-07. Diphoton elastic scattering in UPC at smaller $W_{\gamma\gamma}$. https://arxiv.org/abs/1910.02690

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