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arXiv · 2406.17959

Anomalous soft photons: status and perspectives

R. Bailhache·D. Bonocore·P. Braun-Munzinger·X. Feal·S. Floerchinger·J. Klein·K. Köhler·P. Lebiedowicz·C. M. Peter·R. Rapp·K. Reygers·W. Schäfer·H. S. Scheid·K. Schweda·J. Stachel·H. van Hees·C. A. van Veen·M. Völkl
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Abstract

This report summarizes the work of the EMMI Rapid Reaction Task Force on "Real and Virtual Photon Production at Ultra-Low Transverse Momentum and Low Mass at the LHC". We provide an overview of the soft-photon puzzle, i.e., of the long-standing discrepancy between experimental data and predictions based on Low's soft-photon theorem, also referred to as "anomalous" soft photon production, and we review the current theoretical understanding of soft radiation and soft theorems. We also focus on low-mass dileptons as a tool for determining the electrical conductivity of the medium produced in high-energy nucleus-nucleus collisions. We discuss how both topics can be addressed with the planned ALICE 3 detector at the LHC.

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R. Bailhache, D. Bonocore, P. Braun-Munzinger, X. Feal, S. Floerchinger, J. Klein, K. Köhler, P. Lebiedowicz, C. M. Peter, R. Rapp, K. Reygers, W. Schäfer, H. S. Scheid, K. Schweda, J. Stachel, H. van Hees, C. A. van Veen, M. Völkl. 2024-06-25. Anomalous soft photons: status and perspectives. https://arxiv.org/abs/2406.17959

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