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arXiv · 0806.0556

A study on the anomaly of $p$ over $π$ ratios in $Au+Au$ collisions with jet quenching

Xiaofang Chen·Hanzhong Zhang·Ben-Wei Zhang·Enke Wang
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Abstract

The ratios of $p/π$ at large transverse momentum in central $Au+Au$ collisions at RHIC are studied in the framework of jet quenching based on a next-to-leading order pQCD parton model. It is shown that theoretical calculations with a gluon energy loss larger than the quark energy loss will naturally lead to a smaller $p/π$ ratios at large transverse momentum in $Au+Au$ collisions than those in $p+p$ collisions at the same energy. Scenarios with equal energy losses for gluons and quarks and a strong jet conversion are both explored and it is demonstrated in both scenarios $p/π$ ratios at high $p_T$ in central $Au+Au$ collisions are enhanced and the calculated ratios of protons over pions approach to the experimental measurements. However, ${\bar p}/p$ in the latter scenario is found to fit data better than that in the former scenario.

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Xiaofang Chen, Hanzhong Zhang, Ben-Wei Zhang, Enke Wang. 2009-10-28. A study on the anomaly of $p$ over $π$ ratios in $Au+Au$ collisions with jet quenching. https://doi.org/10.1088/0954-3899%2F37%2F1%2F015004

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