Scientists at CERN Announce Discovery of a New Particle

July 4, 2012, was an historic day in science with researchers at CERN (European Organization for Nuclear Research) announcing the discovery of a new particle that is "consistent with the Higgs boson." It also marked an important period at the University of Rochester as three physicists and an engineer helped support the nearly five-decades-old theory of one of their colleagues.

The four scientists—Arie Bodek, Regina Demina, Aran Garcia-Bellido, and Sergei Korjenevski—were part of CMS, one of the two experimental teams at CERN whose results made the discovery possible. Carl Hagen—along with Gerald Guralnik and Thomas Kibble—wrote the 1964 paper, titled Global Conservation Laws and Massless Particles, which was named one of the milestone papers in the history of Physical Review Letters. Hagen, Guralnik, and Kibble were among the six scientists who came out with similar papers that year describing the Higgs mechanism and the Higgs boson.

Hagen, a professor of physics at the University, made his first trip to CERN in Geneva, Switzerland for the big 4th of July announcement and described the findings of the scientists as a "remarkable achievement. Yet that is not to say that it is the long-sought boson. Its spin has yet to be determined, for example."

The Higgs boson is an elementary particle that's responsible for giving other particles their mass.

Arie Bodek, the George E. Pake Professor of Physics, calls the news from CERN the "most important discovery in particle physics since the '70s." Bodek's 1972 Ph.D. thesis at MIT involved the discovery of the quark, which he considers the first experimental result that led to the formulation of the Standard Model of particle physics.

Bodek's research group at the University of Rochester took the lead in constructing the detectors, called "hadron calorimeters," for the CMS experiment.

"I feel very fortunate to have participated in both of these incredible discoveries," said Bodek.

Professor of Physics Regina Demina, who said she long wanted to be part of the high-energy physics frontier, has been involved with CMS for nearly 12 years.

"Our work at CERN is not done," noted Demina. "We must verify that the new particle discovered has all the qualities expected in the Higgs boson. Beyond that, the model that explains the universe is not yet complete. That includes a better understanding of dark energy and dark matter."

Demina is proud to be part of the CERN experiments, because they "push our fundamental understanding of the universe to a new level."

Aran Garcia-Bellido, assistant professor physics, has been a member of the CMS team since 1994. His particular group works in the operations and upgrade of the hadron calorimeter.

"Our job as experimentalists is to build the detectors that serve as blank slates for the particles to leave their footprints in," said Garcia-Bellido, "and then we understand how those footprints relate to the real particles and what that means about their nature."

The work at CERN would not have been possible without a great many people working at a high level of quality, according to Demina. Among those people is Senior Technical Associate Sergei Korjenevski, an engineer who's responsible for maintaining the quality of the silicon sensors in the CMS detector.

Korjenevski worked on the CMS project for 11 years, his tenure coming to an end in 2010 after the successful commissioning of the detector. He hopes that the discovery of the particle marks the beginning of a new era in our understanding of reality.

As work continues at CERN, a new generation from Rochester is busy leaving its mark. Roberto Covarelli, a postdoctoral fellow under the supervision of Demina, is involved in measuring the spin of the new particle, which, if it is truly the elusive Higgs boson, will be zero.