I once studied at a cyclotron laboratory (mid 1980's) and an already-old comic book circulated amongst the students with a cover showing "Superman vs. the Cyclotronic Man".
I think that the Cyclotronic man was vanquished at the end of the comic book via something that stops normal cyclotrons as well, but don't remember now what that is.
Question: Superman vs The Cyclotronic Man; what was the story arc? How did Superman prevail? Did The Cyclotronic Man die? Was this both the first and last time that The Cyclotronic Man appeared in Superman fiction, or where there other appearances?