[ncmncm]

In a word, slowly. You may reasonably assume that particle physicists are familiar with relativistic time dilation, and how to adjust for it if that were needed.

That is not a universally reasonable assumption. Cosmologists apparently never really tried adjusting their expectations for galaxy rotation for general relativity. When a plasma fluid dynamicist facile with the maths looked, the rotation anomaly evaporated. (Cosmologists were assiduously ignoring this, last I checked.) GR maths are considered hard, except by plasma fluid dynamicists, who have to do actually hard maths just to graduate.