A&S professors research Higgs boson, particle physics in ongoing experiment

From the September 2013 Desktop News | One of the scientists who discovered the “God particle” visited UA August 28 to discuss the milestone discovery.

Dr. Albert de Roeck, a scientist on the research team that recently discovered the Higgs boson — aka the “God particle” — spoke about the discovery, and ongoing research, at an event sponsored by the Department of Physics and Astronomy.

The standard model of particle physics was confirmed with the discovery of the Higgs boson last summer at the European Organization for Nuclear Research (CERN), home to the Large Hadron Collider (LHC), the particle accelerator used to study particle physics. The discovery of the elusive “God particle,” which gives other particles their mass, was hailed as a major achievement in particle physics, opening a path to physics beyond the standard model.

Assistant professors Conor Henderson and Paolo Rumerio, in collaboration with CERN, are part of a team of thousands of physicists involved in the compact muon solenoid (CMS) experiment. Henderson said CMS researchers study evidence of physics beyond the standard model and will continue to study the detailed properties of the newly discovered Higgs boson.

Although Henderson and Rumerio have been working on CMS for 10 years, UA only became involved in 2011. Henderson said UA’s research team consists of two faculty members, two post-doctoral researchers stationed at CERN, one graduate student, and undergraduates who research for one or two semesters at a time.

“CMS is a single detector, but it’s made up of several technologies, each one dedicated to detect a particular type of particle,” Rumerio said. “It is interlaid with sensitive components that detect the presence of particles. We gather our expertise to build, run and operate this really large and complex detector.”

Henderson’s specialty is the trigger system of the CMS, which is the way researchers select the collisions that will be analyzed. The trigger system uses input of electrical signals from the CMS to track collisions.

“As the collisions occur, there are about 40 million events happening per second and that’s far too many to actually record,” Henderson said. “We have to make very fast decisions about which ones we pick and which ones we ignore, the vast majority of which we have to ignore.”

Henderson and Rumerio also analyze the data collected by the experiment and conduct analysis projects, including trying to better understand the Higgs boson. Henderson said researchers suspect that there is additional new physics operating at this energy scale and hope to see evidence for that in the data collected by CMS. One possibility that Henderson and Rumerio specifically study is the existence of extra dimensions of space.

“Now that we’ve discovered the Higgs, we’ve made a wonderful achievement and really solidified that part of the theory,” Henderson said. “But there are several questions that still need to be answered. The LHC is planned to run at least until 2025, so there will be plenty of data to study as we seek signs of new physics beyond the standard model.”