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arXiv · 1707.03949

Quark number scaling of hadronic $p_T$ spectra and constituent quark degree of freedom in $p$-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV

Abstract

We show that the experimental data of $p_T$ spectra of identified hadrons released recently by ALICE collaboration for $p$-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV exhibit a distinct universal behavior --- the quark number scaling. We further show that the scaling is a direct consequence of quark (re-)combination mechanism of hadronization and can be regarded as a strong indication of the existence of the underlying source with constituent quark degree of freedom for the production of hadrons in $p$-Pb collisions at such high energies. We make also predictions for production of other hadrons.

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Jun Song, Xing-rui Gou, Feng-lan Shao, Zuo-Tang Liang. 2017-07-13. Quark number scaling of hadronic $p_T$ spectra and constituent quark degree of freedom in $p$-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV. https://doi.org/10.1016/j.physletb.2017.10.012

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