The Tevatron was the world's most powerful particle accelerator and the site of many of the biggest discoveries in the field for more than two decades. It symbolized the United States' scientific dominance and was the center of the international physics world until it was eclipsed by Europe's Large Hadron Collider last year.

Today, protons and antiprotons will stop speeding around the 4-mile-long circular accelerator track at Fermilab in Batavia, Illinois, and data from the Tevatron's final particle collisions will be recorded. The end will be marked by a ceremony to turn the machine off and celebrate the dozens of discoveries it made, broadcast live online at 2 p.m. central time.

“For the last 28 years, the Tevatron has been the real workhorse of particle physics,” said physicist Paul Halpern of the University of the Sciences in Philadelphia and author of the book Collider. Without it, physicists would have a large gap in their knowledge of the universe, he added.

Over the course of its life, the Tevatron has made a number of remarkable findings related to the Standard Model of physics, which describes the characteristics and behavior of subatomic particles. The facility's two detectors, the Collider Detector at Fermilab (CDF) and DZero experiments, have both competed and worked together to reveal the nature of matter.

Even after Europe's Large Hadron Collider began producing higher-energy beams, and budget constraints forced the lab to schedule its shutdown, the Tevatron continued to perform and put in an impressive ninth-inning effort in pursuit of the still-elusive Higgs boson, the last undiscovered particle predicted by the Standard Model. And there is still a chance it could succeed, as scientists continue to analyze the Tevatron's data, even after the machine goes dark.

Here are some of the Tevatron's greatest achievements.

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The Tevatron accelerates charged particles to extremely high speeds using a four-mile long ring of magnets. The instrument then slams the particles together in order to split them up into their constituents. The Tevatron typically shoots a beam of protons and antiprotons in opposite directions around the ring until they reach a desired energy range and then allows the two beams to meet. The ensuing collision produces a rain of particles that researchers then dig through to search for those predicted by the Standard Model.

The accelerator produces an extremely bright beam of these particles and is able to reach energies up to 1 TeV, or roughly a trillion times the energy of ordinary visible light. The facility was the world-record holder in high-energy physics until it was surpassed by the LHC, which will ultimately be able to reach energies seven times those of the Tevatron’s peak.

Image: Fermilab