Tevatron

John Peoples passed away on June 25, 2025. He was the third director of Fermilab, remembered as a prolific physicist and a hands-on leader.

In 2022, the CDF experiment at Fermilab measured the W boson mass and found a challenge in the predictions of physics. However, the LHC measurement of the mass of the W boson found the exact expected value. What now?

On March 2, 1995, the top quark discovery at Fermilab was announced by scientists on the CDF and DZero collaborations, and the sixth and final quark was added to the Standard Model. We ask two members of the collaborations to reflect on this groundbreaking moment in particle physics.

Listen to the podcast story of Dr. Helen Edwards, who was a Fermilab particle physicist who led the design and construction of the Tevatron to probe deeper into the atom than anyone had gone before.

From New Scientist, Dec. 16, 2022: This year was another busy year in science and technology and New Scientist news editors’ have chosen some of the biggest scientific developments, discoveries and events in 2022. Included in this year’s selections is the April 2022 announcement of the mass of the W boson that used Fermilab’s Tevatron.

From Physics World, July 26, 2022: Appointed by Robert Wilson in 1970, Helen Edwards was the accelerator scientist who oversaw the construction and implementation of the Tevatron, from planning right until the end of its scientific operation. Thirteen years later, the Tevatron was started to later discover the Bc meson in 1998, the top quark in 1995 and the tau neutrino in 2000.

From NBC News, June 14, 2022: The faster and stronger LHC at CERN, scheduled to restart this summer, is stirring up renewed excitement in the discovery of particles that make up dark matter. While the LHC has been dormant for ten years, it has received upgrades while other accelerators like Fermilab’s Tevatron have made discoveries that point to possible “new physics.”

From PBS Space Time, May 25, 2022: Fermilab scientists spent almost a decade recording collisions in the Tevatron collider and another ten years analyzing data finding the W boson’s mass seems to be 0.01 percent heavier than expected. Now, understanding why the particle has mass puts the current Standard Model to the test.

From Nature Italy May 20, 2022: CDF co-spokesperson Giorgio Chiarelli tells the story of how Italy contributed to the measurement of the W boson mass, opening a door on new physics. For more than 10 years after the Tevatron detector at Fermilab produced the last crashes between protons and antiprotons, the collaboration announced the most precise measure of the W boson mass ever achieved.

From the Nature Briefing, May 13, 2022: Based on data recorded with the CDF II detector at Fermilab between 2002 and 2011 at the Tevatron, the collaboration reconstructed more than 4 million W boson candidates through their decays into an electron or muon accompanied by the respective neutrino. The CDF Collaboration stated their result “suggests the possibility of improvements to the standard model calculation or of extensions to it”.