Low‐Energy Lone Electron Exhibits Relativistic Hysteresis

There was to have been a birthday party last September in Gerald Gabrielse's lab at the University of Washington. But, sadly, the young honoree met an untimely end just two months shy of its first birthday. Having inadvertently been allowed a bit too much axial excitation, it collided with the cap electrode of the Penning trap that had been its home for more than ten months, and vanished.