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arXiv · 1510.05449

Can Tsallis distribution fit all the particle spectra produced at RHIC and LHC?

H. Zheng·Lilin Zhu
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Abstract

The Tsallis distribution has been tested to fit the all particle spectra at mid-rapidity from central events produced in d+Au, Cu+Cu, Au+Au collisions at RHIC and p+Pb, Pb+Pb collisions at LHC. Even though there are strong medium effects in Cu+Cu and Au+Au collisions, the results show that the Tsallis distribution can be used to fit most of particle spectra in the collisions studied except in Au+Au collisions where some deviations are seen for proton and $Λ$ at low $p_T$. In addition, as the Tsallis distribution can only fit part of the particle spectra produced in Pb+Pb collisions where $p_T$ is up to 20 GeV/c, a new formula with one more fitting degree of freedom is proposed in order to reproduce the entire $p_T$ region.

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H. Zheng, Lilin Zhu. 2015-08-07. Can Tsallis distribution fit all the particle spectra produced at RHIC and LHC?. https://doi.org/10.1155/2015%2F180491

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