On the latest trip, Todd chilled acrylic slabs to dry-ice temperature before exposing them to the beam. This greatly inhibits the escape of trapped electrons, which allowed him to bring them back home, still chilled. He could wait for a moment of his choosing to release the electrons and make the frozen lightning.
So last week he zapped his slabs in several local places.
The Fermilab Visual Media Services folks videotaped one of his demonstrations, and offered it on Youtube. Take a look.
