%0 Journal Article %T The Study of Noncollectivity by the Forward-Backward Multiplicity Correlation Function %A Na Li %A Shusu Shi %A Aihong Tang %A Yuanfang Wu %J Physics %D 2011 %I arXiv %R 10.1088/0954-3899/39/11/115105 %X We propose a forward-backward multiplicity correlation function $C^N_{FB}$, which is experimentally accessible, to measure the noncollectivity contribution. We find that $C^N_{FB}$ is sensitive to the jet contribution for the particle-rich case. Surprisingly, it will automatically decrease for the particle-rare case. Our study indicates that similar decreasing trend observed previously is mainly driven by particle scarcity instead of jets. The function is studied in Au+Au collision at $\sqrt{s_{NN}}=200$ GeV with a multiphase transport model (AMPT). We find that the jet fraction is about 10% at transverse momentum ($p_T$) around 2.5 GeV/$c$ and reaches up to 30% at 3.5 GeV/$c$. The implication of this study in the investigation of the noncollectivity contribution in elliptic anisotropy parameter $v_2$ is also discussed. %U http://arxiv.org/abs/1112.4242v2