论文标题
非流背景对手性磁波搜索的重要性
Importance of non-flow background on the chiral magnetic wave search
论文作者
论文摘要
对手性磁波（CMW）敏感的观察值是$π^{ - } $和$π^{+} $ anisotropic流动差的电荷不对称依赖性，$ΔV_{n}（a _ _ {\ rm ch}）$。我们表明，由于非流相关性，使用所有带电粒子作为参考将琐碎的线性项引入$ΔV_{n}（a _ {\ rm ch}）$的Q-肿瘤方法的流量测量。对于三角流量差$ΔV_{3}（a _ {\ rm ch}）$的微不足道的斜率贡献，如果非流动由背靠背对支配，则可能为负。这可以解释观察到的负$ΔV_{3}（a _ {\ rm ch}）$ slope在初步恒星数据中。我们进一步发现，非流量相关性从不同的倾斜来源的竞争中引起了$ΔV_{2}（a _ {\ rm ch}）$的斜率，从较大的多重稀释量和$π^{+} $（$π^{ - } $）以阳性（阳性）$（阳性）$ a _ _ =
An observable sensitive to the chiral magnetic wave (CMW) is the charge asymmetry dependence of the $π^{-}$ and $π^{+}$ anisotropic flow difference, $Δv_{n}(A_{\rm ch})$. We show that, due to non-flow correlations, the flow measurements by the Q-cumulant method using all charged particles as reference introduce a trivial linear term to $Δv_{n}(A_{\rm ch})$. The trivial slope contribution to the triangle flow difference $Δv_{3}(A_{\rm ch})$ can be negative if the non-flow is dominated by back-to-back pairs. This can explain the observed negative $Δv_{3}(A_{\rm ch})$ slope in the preliminary STAR data. We further find that the non-flow correlations give rise to additional backgrounds to the slope of $Δv_{2}(A_{\rm ch})$ from the competition among different pion sources and from the larger multiplicity dilution to $π^{+}$ ($π^{-}$) at positive (negative) $A_{\rm ch}$.
