In relativistic heavy-ion collisions the electromagnetic field exists before the hot nuclear matter emergence. Requiring the field continuity we compute it in the central rapidity region by taking into account the electromagnetic response of the Quark Gluon Plasma. We show that the electromagnetic field is nearly time-independent from about 1 fm/c after the collision until the freezeout. In particular, its value is about 10% of the initial magnitude of the magnetic field. Our result provides a theoretical basis for the common assumption that the electromagnetic field produced in relativistic heavy-ion collisions varies slowly with time.

中文翻译：

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重离子碰撞中电磁场的连续演化

在相对论重离子碰撞中，电磁场存在于热核物质出现之前。需要场连续性，我们通过考虑夸克胶子等离子体的电磁响应在中心快速区域计算它。我们表明，从碰撞后的大约 1 fm/c 到冻结，电磁场几乎与时间无关。特别是，它的值大约是磁场初始大小的 10%。我们的结果为普遍假设提供了理论基础，即相对论重离子碰撞中产生的电磁场随时间缓慢变化。