The "God particle" may have to wait.

The Tevatron, a once-cutting edge Chicago-area particle accelerator run by the Fermi National Accelerator Laboratory and played a key role in the quest for the Higgs Boson or "God particle" was shut down for the last time Friday afternoon at 3:40 p.m. EDT. 

"We're thinking of it as if we're pulling the plug on our favorite uncle," said Roger Dixon, who heads the accelerator division at Fermilab, on Thursday.

Helen Edwards, the lead scientist for the construction of the Tevatron in the 1980s, terminated the final store in the Tevatron by pressing a button that activated a set of magnets that steer the beam into the metal target. Edwards then pushed a second button to power off the magnets that have been guiding beams through the Tevatron ring for 28 years.

A live broadcast of the event began at 1 p.m. EDT, allowing Fermilab staff and fans to watch the broadcast, hosted by Fermilab Director Pier Oddone.

“Many exciting measurements and discoveries were made here which helped finalize the model by which we explain the behavior of elementary particles,” Dmitri Denisov, a Fermilab scientist, told “That’s over 1,000 papers published, over 1,000 Ph.D.s defended along with the participation of 40 countries around the world.

There's plenty of research to keep Fermilab at the cutting edge, Fermilab's physicists claim. Denisov said he has plenty of data to analyze, enough to keep him busy for the next year.

There are also efforts to build a new accelerator to study the universe in a new way — by producing the most collisions, rather than the most powerful. The accelerator also would be capable of producing neutrino beams more intense than anywhere else to help study the particles that scientists theorize helped tip the cosmic scales toward a universe made of matter.

"The idea is to look for things that happen very rarely, and the way to find them is to create lots of examples and see if you find something," said Steve Holmes, who's in charge of the new venture, called Project X.

The proposal could cost up to $2 billion, but it has no funding yet. 

By early next year, Fermilab hopes to be able to conclude from Tevatron data that either the Higgs boson does not exist or that it's still a plausible theory. Even if there's evidence of the Higgs boson, it would have to be confirmed -- and that would probably happen in Switzerland.

“A large fraction of U.S. physicists will move to CERN’s LHC, while a substantial number will continue with new neutrino and energy frontier experiments at Fermilab,” Denisov said.

"From the DZero control room, goodbye, and good luck," said Bill Lee, run coordinator for the experiment.