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Net charge fluctuation and string fragmentation

Ben-Hao Sa·Xu Cai·an Tai·Zhong-Qi Wang·Dai-Mei Zhou
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Abstract

We present simulation results of net charge fluctuation in $Au+Au$ collisions at $\sqrt{s_{nn}}$=130 GeV from a dynamic model, JPCIAE. The calculations are done for the quark-gluon phase before hadronization, the pion gas, the resonance pion gas from $ρ$ and $ω$ decays and so on. The simulations of the charge fluctuation show that the discrepancy exists between the dynamic model and the thermal model for a pion gas and a resonance pion gas from $ρ$ and $ω$ decays while the simulated charge fluctuation of the quark-gluon phase is close to the thermal model prediction. JPCIAE results of net charge fluctuation in the hardonic phase are nearly 4-5 times larger than one for the quark-gluon phase, which implies that the charge fluctuation in the quark-gluon phase may not survive the hadronization (string fragmentation) as implemented in JPCIAE.

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Ben-Hao Sa, Xu Cai, an Tai, Zhong-Qi Wang, Dai-Mei Zhou. 2003-05-08. Net charge fluctuation and string fragmentation. https://doi.org/10.1088/0253-6102%2F42%2F3%2F403

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