标题： 角动量的玻璃态介质 显示英文标题

标题： Angular momentum of glasma

摘要： 超相对论重离子碰撞的最早阶段可以描述为一种高度密集的胶子系统，称为胶子血浆。 我们研究了一些与系统角动量相关的胶子血浆特性。 第一个是垂直于反应平面的全局角动量，该平面由束流轴和冲击参数矢量构成。 我们表明，碰撞的超相对论核的巨大初始角动量只有很小一部分被转移到了胶子血浆中。 我们的主要关注点是沿束流轴方向的胶子血浆角动量。 这个量具有局部性质，是由胶子血浆中产生的非均匀速度场引起的。 我们计算了涡度和局部角动量，它们表现出明显不同的行为。 结果进行了详细分析，并在现有实验数据的背景下进行了讨论。 我们认为，控制终态强子极化的既不是涡度也不是热涡度，而是局部角动量。 显示英文摘要

摘要： The earliest phase of an ultrarelativistic heavy ion collision can be described as a highly populated system of gluons called glasma. We study some glasma characteristics related to the system's angular momentum. The first one is the global angular momentum perpendicular to the reaction plane, which is spanned by the beam axis and impact parameter vector. We show that only a small fraction of the enormous initial angular momentum of the colliding ultrarelativistic nuclei is transferred to the glasma. Our main focus is the glasma angular momentum directed along the beam axis. This quantity has a local character and results from the inhomogeneous velocity field generated in the glasma. We calculate the vorticity and local angular momentum which show noticeably different behaviour. The results are analyzed in detail and discussed in the context of existing experimental data. We argue that neither vorticity nor thermal vorticity but instead the local angular momentum controls the polarization of final-state hadrons.