By Gail Gallessich

On the fifth floor of Broida Hall, UCSB physicists, technicians, graduate and undergraduate students have quietly built high-precision particle tracking devices made of silicon. These are key ingredients in what may be the largest international scientific particle research collaboration that the world has ever known, one that will probe energies that have not existed since the first instant after the Big Bang.

Inserted in a massive particle accelerator component, called the Compact Muon Solenoid, or CMS, the tracking devices will allow experimenters to follow what happens when protons collide with protons at extremely high energies.

Approximately one-quarter of the CMS tracking units were built at UCSB. The 2.6 million channels of electrons constitute the single largest part of the tracking system built at one location.

Helping to guide construction of these detection devices were physics professors Joseph Incandela and Claudio Campagnari. “This is a very exciting time for elementary particle physics; the experiments will have a major impact on physics,” said Incandela.

“The experiments will reach extremely high temperatures that have not existed since the Big Bang,” said Incandela, who recently was named deputy physics coordinator, the second in command, of the entire CMS science project.

“The particles we hope to create were abundant at that point. This experiment could see evidence for the Higgs, the particle that causes other particles to have mass, or for dark matter. These are a couple of many, many possibilities of what we may see.”

The CMS experiments will be conducted in the Large Hadron Collider (LHC) accelerator at CERN, the European Organization for Nuclear Research, which sits astride the Franco-Swiss border near Geneva. It is the world’s largest particle physics center. The 17-mile underground loop of the accelerator occupies a space larger than the Geneva Airport.

Incandela will work there with physics coordinator Paris Sphicas, a Greek scientist with CERN. They will coordinate the physics studies of 2,030 physicists from 38 countries and 174 institutions.

Incandela explained that the center of mass collision energy would be 14 trillion electronic volts in the LHC. The beams of energy used in the attempt to understand the fundamental forces of nature will be thinner than a human hair. “We will be able to probe a critical range of energy where we believe important clues must exist about the real nature of forces and particles in our universe,” he said.

“The UCSB physicists working on CMS are faced with an opportunity that comes along once every 20 years, the chance to make revolutionary discoveries about the nature of matter, space, and time,” said Michael Witherell, UCSB vice chancellor for research and a former director of Fermilab, which is also a part of the CMS project.

“For us, the startup of the Large Hadron Collider will be like the launching of the Hubble Space Telescope.”

Incandela will move to CERN this summer, and the experiments are expected to begin pilot operation before the end of the year. Besides Campagnari, he will work with UCSB physics professors David Stuart and Jeffrey Richman.

Incandela said that construction of the particle detectors was very stressful and that he felt 10 years younger once the units were completed and placed in the CMS detector. He worried about everything, even earthquakes, that might ruin the detectors before they were completed and shipped out.