An international collaboration of scientists have sent the first beam of protons zooming at nearly the speed of light around the 17-mile-long underground circular path of the Large Hadron Collider (LHC), the world's most powerful particle accelerator, located at the CERN laboratory near Geneva, Switzerland.

The scientists also accelerated a second beam of protons through the path in the opposite direction, the goal being head-on collisions of protons that can offer clues to the origin of mass and new forces and particles in the universe. The second beam made one turn around the LHC.

Celebrations across the United States and around the world mark the LHC's first circulating beams, an occasion more than 15 years in the making.

An estimated 10,000 people from 60 countries have helped design and build the accelerator and its massive particle detectors, including more than 1,700 scientists, engineers, students and technicians from 94 U.S. universities and laboratories supported by the U.S. Department of Energy Office of Science and the National Science Foundation.

UCR faculty Robert Clare, John Ellison, J. William Gary, Gail Hanson and Stephen Wimpenny, along with postdoctoral scientists and graduate students are involved in the LHC's Compact Muon Solenoid (CMS) experiment, a large particle-capturing detector whose discoveries are expected to help answer questions such as:

Are there undiscovered principles of nature? What is the origin of mass?

Do extra dimensions exist?

What is dark matter?

How can we solve the mystery of dark energy?

And how did the universe come to be?

"After many years of preparation, particle physics is taking a huge step towards understanding whether our theories about the origin of mass are correct and whether there is new physics that can explain dark matter and help us understand dark energy and the origin of the universe," said Hanson, a distinguished professor of physics, who currently is at CERN.

"Particle physicists from UCR have been involved in the CMS experiment since its beginning, and have been working to construct and commission parts of the detector. They will soon be able to carry out the measurements and make the discoveries that have been dreamed of for so long."

It will take about a month for scientists to align the proton beams traveling in opposite directions in the LHC so that proton-proton collisions are generated. The LHC will create almost a billion such collisions per second at an energy of 14 trillion electron volts.

These collisions will take place at four points around its 17-mile ring, where the four main LHC experiments, including CMS, are located.

"This is an extremely important moment," said Clare, a professor of physics.

"We are now on the verge of making hopefully many discoveries over the next years in our understanding of particle physics and how the universe works. For the first time in a long time, we will be breaking new ground. We may discover the Higgs boson; we may discover supersymmetry. We may discover completely new and unexpected phenomena, which would be by far the most exciting prospect."

UCR postdoctoral researchers and students doing work related to the CMS experiment are: Avdhesh Chandra, Feng Liu, John Babb (currently at CERN), Geng-yuan "Greg" Jeng (currently at CERN), Shih-chuan "Kevin" Kao (currently at CERN), Hongliang Liu, Arun Luthra, Harold Nguyen, Robert Stringer (currently at CERN), Jared Sturdy (currently at CERN), Rachel Wilken, and Manatosh "Milton" Bose.

"As the largest and most powerful particle accelerator on Earth, the LHC represents a monumental technical achievement," said U.S. Department of Energy Undersecretary for Science Raymond L. Orbach, who is a former UCR Chancellor.

"I congratulate the world's scientists and engineers who have made contributions to the construction of the accelerator for reaching this milestone. We now eagerly await the results that will emerge from operation of this extraordinary machine."

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Large Hadron Collider to reach full capacity by year end
Scientists are planning to run the world's largest particle collider at full capacity by the end of 2008, a Russian physicist told RIA Novosti on Wednesday.

During the first full tests conducted Wednesday, beams of sub-atomic particles were for the first time sent round the accelerator ring in opposite directions at almost the speed of light, but the powerful superconductor magnets in the collider operated at minimum capacity.

"The Large Hadron Collider (LHC) is an extremely complex system," said Vladimir Karzhavin of the Joint Institute for Nuclear Research in Dubna. "That is why its initial launch is a very complicated and sensitive process."

The physicist, who heads of a team of Russian scientists from the institute who participate in the LHC project, said collisions initially would be rare and involve low-energy protons, but over time the frequency and energy output would gradually increase.

"By the end of this year-beginning of next year we are planning to reach the maximum collision energy of 14 TeV," Karzhavin said.

According to the design of the experiment, the work of the collider will stop in March 2009 to give the scientists six months to analyze the data acquired and check the condition of the system.

The LHC is based 100 meters below ground, with a circumference of 27 km, and is operated from the control room of the European Organization for Nuclear Research, known by its French initials as CERN.

Many scientists hope the experiment will reveal the Higgs boson, nicknamed the "God particle," a concept hypothesized in the 1960s to explain how atoms acquire mass. Discovering the particle could explain how matter appeared in the split-second after the Big Bang.

The international LHC project has involved more than 2,000 physicists from hundreds of universities and laboratories in 34 countries since 1984. Over 700 Russian physicists from 12 research institutes have taken part.