اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of higher cumulants of net-charge multiplicity distributions in Au$+$Au collisions at $sqrt{s_{_{NN}}}=7.7-200$ GeV
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We report the measurement of cumulants ($C_n, n=1ldots4$) of the net-charge distributions measured within pseudorapidity ($|eta|<0.35$) in Au$+$Au collisions at $sqrt{s_{_{NN}}}=7.7-200$ GeV with the PHENIX experiment at the Relativistic Heavy Ion Collider. The ratios of cumulants (e.g. $C_1/C_2$, $C_3/C_1$) of the net-charge distributions, which can be related to volume independent susceptibility ratios, are studied as a function of centrality and energy. These quantities are important to understand the quantum-chromodynamics phase diagram and possible existence of a critical end point. The measured values are very well described by expectation from negative binomial distributions. We do not observe any nonmonotonic behavior in the ratios of the cumulants as a function of collision energy. The measured values of $C_1/C_2 = mu/sigma^2$ and $C_3/C_1 = Ssigma^3/mu$ can be directly compared to lattice quantum-chromodynamics calculations and thus allow extraction of both the chemical freeze-out temperature and the baryon chemical potential at each center-of-mass energy.
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