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arXiv · 1904.00304

Study of angular correlations in Monte Carlo simulations

Balázs Endre Szigeti·Monika Varga-Kofarago
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Abstract

In two-particle angular correlation measurements the distribution of charged hadron pairs are evaluated as a function of pseudorapidity ($\Delta \eta$) and azimuthal ($\Delta \varphi$) differences. In these correlations, jets manifest themselves as a near-side peak around $\Delta \eta = 0,$ $\Delta \varphi = 0$. These correlations can be used to extract transverse momentum ($p_T$) and centrality dependence of the shape of the near-side peak in Pb-Pb collision. The shape of the near-side peak is quantified by the variances of the distribution. The variances are evaluated from a fit combining the peak and the background. In this contribution, identified and unidentified angular correlations are shown from Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV from Monte Carlo simulations (AMPT, PYTHIA 8.235/Angantyr). Results show that transport models in AMPT give better results than PYTHIA 8.235/Angantyr when comparing to the experimental results of the ALICE collaboration.

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Balázs Endre Szigeti, Monika Varga-Kofarago. 2019-03-30. Study of angular correlations in Monte Carlo simulations. https://arxiv.org/abs/1904.00304

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