We can produce energetic gamma-rays on Earth in nuclear reactions but also among the decay products of LHC particle collisions.
So I was wandering which are exactly the highest energy man-made gamma-rays we have produced so far?
My intuition is that they come from the decay of neutral pions $\pi_0 \rightarrow 2 \gamma$ at LHC collisions, if yes, which energy can they reach? Or is there some other process I am not considering? I dismissed nuclear reactions as they typically produce MeV particles while, even though I am not an expert, I am sure LHC produces at least GeV pions.