Long-distance ultraperipheral collisions of two relativistic ions are considered. Clouds of photons surrounding the ions are responsible for their distant electromagnetic interaction. The perturbative approach and the method of equivalent photons are described. It is shown that the total cross section of these collisions rapidly increases with an energy increase and is especially large for heavy ions. Some experimental data and their comparison with theoretical approaches are described. Further proposals are discussed.

中文翻译：

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超外周核相互作用

考虑两个相对论离子的长距离超外围碰撞。离子周围的光子云是它们远距离电磁相互作用的原因。描述了微扰方法和等效光子方法。结果表明，这些碰撞的总截面随着能量的增加而迅速增加，对于重离子尤其大。描述了一些实验数据及其与理论方法的比较。进一步的建议进行了讨论。