Particle beams are once again zooming around the world's most powerful particle
accelerator-the Large Hadron Collider-located at the CERN laboratory near Geneva,
Switzerland. On November 20 at 4:00 p.m. EST, a clockwise circulating beam was
established in the LHC's 17-mile ring.

The LHC's 17-mile-long string of magnets has been repaired and beams are once more circulating in the world's most powerful particle accelerator. (Courtesy CERN)
After more than one year of repairs, the LHC is now back on track to create
high-energy particle collisions that may yield extraordinary insights into the
nature of the physical universe.
“The LHC is a machine unprecedented in size, in complexity, and in the
scope of the international collaboration that has built it over the last 15
years,” said Dennis Kovar, U.S. Department of Energy Associate Director
of Science for High Energy Physics. “I congratulate the scientists and
engineers that have worked to get the LHC back up and running, and look forward
to the discoveries to come.”
American scientists have played an important role in the construction of the
LHC. About 150 scientists, engineers and technicians from three DOE national
laboratories-Brookhaven Lab, Fermilab and Berkeley
Lab-built critical accelerator components. They are joined by colleagues
from DOE's SLAC National Accelerator Laboratory and the University of Texas
at Austin in ongoing LHC accelerator R&D. The work has been supported by
the DOE Office of Science.
Circulating beams are a major milestone on the way to the ultimate goal: data
from high-energy particle collisions in each of the LHC's four major particle
detectors. Over the next few months, scientists will create collisions between
two beams of protons. These very first LHC collisions will take place at the
relatively low energy of 900 GeV. They will then raise the beam energy, aiming
for collisions at the world-record energy of 7 TeV in early 2010. With these
high-energy collisions, the hunt for discoveries at the LHC will begin.
“It's great to see beam circulating in the LHC again” said
CERN's Director for Accelerators, Steve Myers. “We've still
got some way to go before physics can begin, but with this milestone we're
well on the way.”
In all, an estimated 10,000 people from 60 countries have helped design and
build the LHC accelerator and its four massive particle detectors, including
more than 1,700 scientists, engineers, students and technicians from 97 U.S.
universities and laboratories in 32 states and Puerto Rico supported by the
DOE Office of Science and the National Science Foundation.