This Day in Fermilab History: March 1, 1972


Lab director Robert R. Wilson and others celebrate the accelerator achieving an energy of 200 GeV.

After years of design and construction, the NAL Main Ring achieved its design energy of 200 GeV on March 1, 1972, ahead of schedule and under its authorized $250 million budget.

The NAL Accelerator Section had achieved a beam of 20 GeV on Jan. 22, 53 GeV on Feb. 4, and 100 GeV on Feb. 11, surpassing the 76-GeV machine at Serpukhov in the U.S.S.R. which, up until that point, had been the most powerful accelerator in the world. By the morning of March 1, the lab employees knew they were on the cusp of achieving the design energy they had been striving towards. By 11 a.m., they had a steady, stable beam. At 12:30 p.m., the beam reached a new record of 167 GeV, and people began gathering around the screen in the Control Room to watch the beam’s progress. At 1:08 p.m., the crowd cheered as the beam passed 200 GeV for the first time. The achievement was followed by a lively labwide celebration.

The lab quickly surpassed this 200-GeV energy goal, reaching 300 GeV on July 16, 1972, and 500 GeV on May 14, 1976.

You can read about the achievement of 200 GeV in the March 9, 1972, Village Crier. You can also read the Main Ring logbook entry from March 1, 1972, which includes signatures by many of the people present for the event.

Visit the history website for more photos of this day in Fermilab history.

The seventh page from the Main Ring logbook entry for March 1, 1972. Note the “Hip hip hooray!” on the pasted-in printout.