MIT Department of Electrical Engineering & Computer Science

MIT's Building 20: The Magical Incubator Story, Anecdote, or Reminiscence

All-nighters in the Atomic Beam Lab

Josef Eisinger
'51

From 1949 to 1951 while doing my thesis research in Prof. Jerrold Zacharias's (Zach's) Atomic Beam Lab (RLE), I spent many a night in Building 20: not only because graduate students had a predilection for working through the night, but also to avoid the fluctuations in the magnetic field which interfered with our experiments. We had traced these magnetic disturbances to surging ground currents whenever a subway train left a station and were obliged to perform our most delicate measurements between 2 and 6 am when the subway closed down. We would prepare our runs in the evening, often strengthened by an onion sandwich (10 cents) with ketchup at the diner (affectionately known as The Armpit) on Mass Avenue. At 7 am we had breakfast and went to sleep till noon.

In our experiments we induced transitions between the magnetic substates of atoms traveling through specially designed magnetic fields, all within an 8 foot long high vacuum chamber. The fields were generated by high currents supplied by banks of huge decommissioned submarine batteries, donated to Zach by the obliging US Navy. Between the wings of Building 20 there were at the time horseshoe courts and we schemed to wrap subterranean coils around the iron stakes of the court next to our lab, connect the coils to our batteries and astonish one and all with dramatic "leaners" and "ringers", whenever an accomplice turned on the juice. Like all the best practical jokes, this one was never actually executed.