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arXiv · 2512.22358

Can high-$p_\perp$ theory and data constrain $\eta/s$?

Bithika Karmakar·Dusan Zigic·Igor Salom·Jussi Auvinen·Pasi Huovinen·Marko Djordjevic·Magdalena Djordjevic
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Abstract

Understanding the temperature dependence of the specific shear viscosity $(\eta/s)$ is crucial for characterizing the properties of the QCD matter produced in ultrarelativistic heavy-ion collisions. Since, low-$p_\perp$ theory and data are only weakly sensitive to the typical forms of $\eta/s(T)$, especially at high temperatures, we use high-$p_\perp$ data and theory to impose additional constraints on it. Our approach, based on dynamical radiative and collisional energy loss of high-$p_\perp$ particles, provides promising results in constraining the temperature dependence of $\eta/s$.

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Bithika Karmakar, Dusan Zigic, Igor Salom, Jussi Auvinen, Pasi Huovinen, Marko Djordjevic, Magdalena Djordjevic. 2025-12-26. Can high-$p_\perp$ theory and data constrain $\eta/s$?. https://doi.org/10.1016/j.jspc.2025.100190

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