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arXiv · 2401.14282

How far can we see back in time in high-energy collisions using charm hadrons?

Laszlo Gyulai·Gabor Biro·Robert Vertesi·Gergely Gabor Barnafoldi
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Abstract

We use open charm production to estimate how far we can see back in time in high-energy hadron-hadron collisions. We analyze the transverse momentum distributions of the identified D mesons from pp, p--Pb and A--A collisions at the ALICE and STAR experiments covering the energy range from $\sqrt{s_{\rm NN}} = 200$~GeV up to 7~TeV. Within a non-extensive statistical framework, the common Tsallis parameters for D mesons represent higher temperature and more degrees of freedom than that of light-flavour hadrons. Assuming Bjorken-expansion, the production of D mesons corresponds to a significantly earlier proper time, $\tau_{\rm D} = (0.18 \pm 0.06) \tau_{\rm LF}$.

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Laszlo Gyulai, Gabor Biro, Robert Vertesi, Gergely Gabor Barnafoldi. 2024-01-25. How far can we see back in time in high-energy collisions using charm hadrons?. https://doi.org/10.1088/1361-6471%2Fad59b9

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