Contact: Bob Nelson For immediate release
(212) 854-6580 January 30, 1998
[email protected]
Columbia To Build $13 Million In Electronics
To Detect New Events At Large Hadron Collider
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Scientists Hope European Machine Will Show Why Matter Has Mass
Columbia University physicists will receive $13 million to build some of the
most sensitive electronics ever made to detect bursts of new particles within the
Large Hadron Collider, the European accelerator that may reveal why matter has
mass.
The electronics, one of several University collaborations to construct the
collider, are to be built by a Columbia team directed by John Parsons, associate
professor of physics. They will measure the energies of dozens of particles created
when two protons moving nearly at the speed of light collide within the ATLAS
particle detector, one of four at the collider. Physicists expect about 40 million
such collisions to occur each second in the space of five centimeters, or about two
inches. The unique electronics will therefore have to handle this huge rate of
collisions while maintaining a precision of 0.25 percent.
With a circumference of almost 17 miles spanning the French-Swiss border
outside Geneva, the Large Hadron Collider when completed in 2005 at a cost of
nearly $6 billion will be the world's most powerful particle accelerator,
reproducing conditions that existed a fraction of a second after the Big Bang. It is
being built at the European Laboratory for Particle Physics, known as CERN.
Under an agreement signed by American and European negotiators Dec. 13
in Washington, the United States will contribute $531 million over the project's 9-
year construction period. The agreement ends four years of complex negotiations
over details such as the U.S. contribution, which is capped at that amount, and
the access to be granted to U.S. physicists, who will be full research partners.
William J. Willis, the Higgins Professor of Physics at Columbia and
American spokesman for the ATLAS experiment, will manage $165 million of
that amount for the ATLAS detector. The funding goes to national laboratory and
university subcontractors providing various pieces of equipment.
The project was almost derailed early last year when some members of
Congress expressed concern about U.S. fiscal exposure to the international
project. Professor Willis and Ellen S. Smith, assistant vice president and director
of federal relations at Columbia, organized a group of scientists and government
relations staff to educate key members of Congress, an effort that helped return
the LHC to the Congressional agenda.
While there is a long history of international collaboration in high-energy
physics accelerators, this is the first time the United States will contribute to the
construction of an accelerator outside its borders. The funding also marks a new
and expanded role for the National Science Foundation, which is contributing $81
million to create the particle detectors. The Department of Energy will give $250
million for the detectors. In-kind federal contributions of $200 million will help
build the accelerator.
After Congress ended funding for the Superconducting Super Collider in
1993, American physicists doing fundamental particle research at the energy
frontier had only one option left: CERN. "This international collaboration
assures that American physicists will have access to the best new facilities
available anywhere," Professor Willis said.
The Large Hadron Collider's two general purpose particle detectors, each
five stories high, weighing thousands of tons and costing nearly $1 billion apiece,
will record the shower of subatomic particles from the collisions. Two smaller
detectors will serve more specialized purposes. Columbia's research team,
including research scientists Michal Seman and Misha Leltchouck, played a
central role in the design of a key element of the ATLAS detector, called an
electromagnetic calorimeter, which captures these particles and measures their
energy. Using these results, scientists can attempt to reconstruct what took place
in the high energy collisions, and can search for the signatures of new particles
or other unexpected phenomena.
The calorimeter, which is of a general type first proposed by Professor
Willis and colleagues more than 20 years ago, uses electrified lead plates and
liquid argon, a dense, nonreactive substance, to detect particles created in
collisions. It is to be fabricated at three sites in France.
The electronic system that detects collisions for ATLAS "pushes the state of
the art," Professor Parsons said. It is spread across a barrel-shaped space about
seven meters long inside the detector and will be divided into some 200,000 tiny
squares, each of which can detect a particle and measure its energy, so that the
direction of the ejected particles can be determined as well as their energy.
The electronics are to be designed and constructed at Columbia's Nevis
Laboratories, Irvington, N.Y., in Westchester County 20 miles north of
Manhattan. Professor Parsons and research scientists Nicolo Cartiglia and Al
Gara, along with the Nevis engineering staff, make use of the sophisticated
facilities of the W.M. Keck Microelectronics Laboratory, established at Nevis
through a grant from the W.M. Keck Foundation.
The system should be ready for final production by 2000, Professor Parsons
said. The Columbia group, including Professor Parsons and research scientist
Jeremy Dodd, also will be among the foremost analysts of the results once the
LHC begins operation in 2005.
The new collider will help scientists answer questions such as: Why does
matter have mass? Why is the universe made mostly of matter, not antimatter?
Are there still more fundamental particles yet unknown to physics? Do these
particles make up the universe's "dark matter," the mysterious substance that
makes up 90 percent of the universe but has never been seen?
The current theory, known as the Standard Model, postulates that particles
acquire mass, defined as resistance to acceleration, through their interaction
with a so-called Higgs field that permeates all space. According to this theory, an
as yet undiscovered particle, the Higgs boson, would have to exist. The LHC
should prove once and for all whether it actually does exist.
Many physicists are skeptical, Professor Parsons said. "From the theory
and from previous experiments, we know that the Higgs boson, if it exists, must
have a mass within a certain range. However, there are theoretical reasons
suggesting a mass in this range would not be very natural." One popular solution
is supersymmetry, in which every particle has a cognate called a superparticle.
No such supersymmetrical particles have ever been observed, but the LHC could
well find some, Professor Parsons said.
The Large Hadron Collider is being built by a consortium of 19 countries
inside an existing accelerator tunnel that crosses the French-Swiss border. Radio
frequency waves will accelerate the two beams of protons, then powerful
superconducting magnets will guide the counter-rotating beams to collision
points inside the detectors. The collision energy of 14 trillion electron volts will be
seven times greater than the world's present highest-energy accelerator, the
Tevatron at the U.S. Department of Energy's Fermilab in Batavia, Ill.
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