标题： 宽偏离侧的方位角关联：高能核碰撞中3体与2体末态粒子 显示英文标题

标题： The broad away side of azimuthal correlations: 3 vs 2 final state particles in high energy nuclear collisions

摘要： 在RHIC的高能重离子碰撞中，介质诱导的动力学存在一些重要的方面，目前仍不完全清楚。 特别是，在Au+Au碰撞的方位角关联研究中出现的远离方向峰的展宽甚至双峰结构，在相同能量的p+p碰撞中并不存在。 这些特征在p+p碰撞中已经存在，但被抑制：2到3个部分子过程会产生这样的结构，但相对于2到2个部分子过程被抑制。 我们认为，在A+A碰撞中，最终态中3个粒子与2个粒子轨迹的不同几何结构，以及不同截面的介质诱导能量损失效应，创造了一个增强最终态包含3个粒子的过程的场景，这平均上给出了这种双峰结构。 显示英文摘要

摘要： In high energy heavy ion collisions at RHIC there are important aspects of the medium induced dynamics, that are still not well understood. In particular, there is a broadening and even a double hump structure of the away-side peak appearing in azimuthal correlation studies in Au+Au collisions which is absent in p+p collisions at the same energies. These features are already present but suppressed in p+p collisions: 2 to 3 parton processes produce such structures but are suppressed with respect to 2 to 2 processes. We argue that in A+A collisions the different geometry for the trajectories of 3 as opposed to 2 particles in the final state, together with the medium induced energy loss effects on the different cross sections, create a scenario that enhances processes with 3 particles in the final state, which gives on average this double hump structure.