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arXiv · 2610.04738

Particle emission from $^{40}$Ar nuclei excited in fixed-target $^{208}$Pb+$^{40}$Ar UPC at the LH

P. Jucha·M. Klusek-Gawenda·K. Mazurek·L. L. Pappalardo·K. Pysz·A. Szczurek
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Abstract

Ultraperipheral collisions of heavy ions, dominated by the electromagnetic interaction, allow to investigate the photoproduction of baryons and mesons from the excited nuclei. At LHCb, thanks to the SMOG2 system, these studies can also be conducted in fixed-target collisions, exploiting a variety of target gases ranging from $^{4}$He to Xe. In the present work, we adapted our photonuclear model and the Giesen-Boltzmann-Uehling-Uhlenbeck (GiBUU) generator to study photoproduction of protons, neutrons as well as pions and kaons from excited $^{40}$Ar nuclei in fixed-target ultraperipheral collisions with the LHC $^{208}$Pb beam. We present predictions for the total and differential photoproduction cross sections in $p$ and $p_T$, both in the full phase-space and within the geometrical acceptance of the LHCb detector.

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P. Jucha, M. Klusek-Gawenda, K. Mazurek, L. L. Pappalardo, K. Pysz, A. Szczurek. 2026-10-03. Particle emission from $^{40}$Ar nuclei excited in fixed-target $^{208}$Pb+$^{40}$Ar UPC at the LH. https://arxiv.org/abs/2610.04738

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