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Topic Name: Find out what, exactly, the universe is made of and how it works.
Category: Systems Optimization
Research persons: John Hauptman
Location: Ames, Iowa 50011, (515) 294-4111.,Iowa State University of Science and Technology, United States
Details
John Hauptman stood before an international gathering of particle physicists
and announced he had another idea.
One that was different. One that was simpler. And best of all, one that he
was sure would work.
It was the August 2005 meeting of the physicists working and hoping to create
the next huge thing in particle physics, the International Linear Collider. As
proposed, the collider would be about 19 miles long and would accelerate
electrons and positrons to nearly the speed of light. The particles would
collide at the center of the machine at extremely high energies of 500 billion
electron volts. The collisions would create new particles for physicists to
study. Physicists are hoping those studies will lead to insights into dark
matter, supersymmetry, extra dimensions -- in other words, they want to find out
what, exactly, the universe is made of and how it works.
Two big detectors would record each of those collisions -- that's 14,000
collisions every second -- and each of the particles they create.
When Hauptman addressed his fellow physicists, three proposals to build the
collider's particle detectors were on the table -- the Silicon Detector by a
mostly American research team, the Global Large Detector by a mostly Japanese
team and the Large Detector Concept by a mostly European team. Big groups of
scientists backed by major laboratories had worked for years on designs for
detectors capable of producing unprecedented performance and resolution. Those
machines would be super sophisticated, cost up to $500 million and contain tens
of millions of channels that would have to work together to measure the energy
of all those particles. Those ambitious and innovative concepts weren't -- and
have not been -- fully demonstrated.
Well, Hauptman stood before the physicists gathered in Snowmass, Colo., and
said, "I have another idea."
And he offered up a detector for the linear collider that's now known as the
"4th Concept."
"It was bold to walk into this -- which John did -- when it looked like there
were three strong groups fighting for two places," said Barry Barish, the
director of the International Linear Collider and Linde Professor of Physics
Emeritus at the California Institute of Technology in Pasadena.
The response to Hauptman's stepping in with a 10-minute talk and launching a
new effort?
"Imagine what it would be like if you were proposing the wheel for the first
time," said Alexander Mikhailichenko an accelerator physicist from Cornell
University in Ithaca, N.Y., who was at that Snowmass session and is now
collaborating on the 4th Concept
Hauptman's idea was to design a simpler detector that could compete for one
of the two spots at the International Linear Collider. It would be one-third to
one-half the cost of the other proposals. And it would feature four subsystems,
two of which are considered innovative technologies:
- a dual-readout calorimeter that measures the energy of particles and
identifies particle types such as muons
- and, an iron-free muon spectrometer capable of detecting muons, particles
sometimes called the "big brother" of the lighter electrons.
Mikhailichenko said the spectrometer's design eliminates 10,000 tons of iron
surrounding the detector without sacrificing resolution. And he said the
detector's design is modular so new and improved components can easily be
switched in and out.
Nural Akchurin, an associate professor of physics at Texas Tech University in
Lubbock, helped develop the dual-readout calorimeter. He said the concept has
been proven and he has data and results to support it. He expects continued
testing will offer more proof.
"To me, this is a purely scientific approach to our experiment," Akchurin
said. "There was no money to gain. No money to lose. No fame to gain. We say
what we think is right and that's just it."
And the 4th Concept collaborators say their detector is the right one for the
job at the International Linear Collider.
"All four subsystems separately achieve the important scientific goal to be
two- to 10-times better than the already excellent (Large Electron-Positron)
detectors ALEPH, DELPHI, L3 and OPAL," says a summary of the project. "As an
integrated detector concept, we achieve comprehensive physics capabilities that
put all conceivable physics at the International Linear Collider within reach."
As the idea has advanced, the 4th Concept research team has grown to include
70 members from Iowa State, Cornell, Texas Tech, the Fermi National Accelerator
Laboratory in Illinois and the University of New Mexico plus researchers from
Italy, France, South Korea, China, Romania, Turkey and Ukraine. The team is
working to add $2 million to the $100,000 it has attracted for research and
development. The concept is now considered a competitor for a detector spot at
the International Linear Collider.
And Hauptman is optimistic about the concept's future.
Because the 4th Concept is fundamentally different that the other proposals,
Hauptman said his team's detector would be able to make measurements that are
comparable and complementary to the other detector.
"We are the complementary detector," he said.
But any decisions about the International Linear Collider and its detectors
are still years away, said Barry Barish of the international collider and
Caltech. Researchers are working to develop engineering designs and plans for
the collider itself. Any decisions to build the collider will probably happen
sometime after 2010.
Barish said the process for selecting two detectors for the collider is just
being discussed. Decisions about which detectors to build will could extend
beyond the decision to actually build the collider.
And yes, he said the 4th Concept is part of the international collider's
detector discussions. The idea sometimes gets left out because it's so much
newer than the other proposals. But Barish said there is plenty of time for the
concept to catch up to the others.
"The 4th Concept is welcomed and encouraged," Barish said. "In the end, it's
my hope and belief that the best ideas are what will be used in these
detectors."
About Researcher:
John Hauptman
A411 Physics Addition
294-8572
hauptman@iastate.edu
high-energy.physics.iastate.edu
Office Hours: anytime by appt.
Univ. of California, Berkeley BA '68 Univ. of California, Berkeley PhD '74
Funded:
The concept is now considered a competitor for a detector spot at the
International Linear Collider..70
members from Iowa State, Cornell, Texas Tech, the Fermi National Accelerator
Laboratory in Illinois and the University of New Mexico plus researchers from
Italy, France, South Korea, China, Romania, Turkey and Ukraine. The team is
working to add $2 million to the $100,000 it has attracted for research and
development.
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