Perhaps thats what would happen if you put your hand in the electron beam at the LHC, but a million times more energetic.
One extremely-high energy particle is way, way less dangerous than a bunch of billions of less energetic particle... repeated every 25 nanoseconds!
If you don't slow them down, they'll just traverse other uranium nuclei and the reaction will only proceed with its natural speed (half-life of billion of years).
That's why you need a minimum mass of uranium for a nuclear explosion: you need neutrons to traverse a certain thickness of material before it gets slow enough to excite other nuclei
Looks like he survived the incident and even completed his PhD in following years. He did lose hearing on one ear and was partially paralyzed though.
Now the particle mentioned in the article was million time more energetic so...