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TALLAHASSEE, Fla. -- How is matter created? What happens when stars
die? Is the universe shrinking, or is it expanding? For decades,
scientists have been looking for answers to such "big picture" questions.
For the past few months, members of the department of physics at
Florida State University have begun using a groundbreaking new research
facility to conduct experiments that may help provide answers to just such
questions.
RESOLUT -- short for "REsonator SOLenoid with Upscale Transmission" --
is the name of the facility, which is located within the John D. Fox
Superconducting Accelerator Laboratory on the FSU campus. Over the past
few months, FSU researchers have begun using RESOLUT to create very rare,
extremely short-lived radioactive particles similar to those that form
inside exploding stars -- and then using the analytical data produced in
the experiments as the basis for hypotheses about the behavior of matter
and the physical properties governing the universe.
"We're doing experiments that replicate, in a very controlled manner,
the explosions that take place in stars," said Ingo Wiedenhover, an
associate professor of physics at FSU who heads up the RESOLUT team. "This
helps us understand the nuclear processes that occur in stars, the origin
of elements,and how stars explode."
Getting to this point has been an arduous process that began in 2002.
"After five years of proposals, fundraising, designing, building and
carefully testing RESOLUT, we are very excited that it has now come online
for experiments," said Samuel L. Tabor, a professor of physics at FSU who
directs the John D. Fox Superconducting Accelerator Laboratory. "To my
knowledge, only one other university in the entire United States has a
facility similar to RESOLUT, so our students have a pretty unique
opportunity to receive hands-on experience that they can get almost
nowhere else."
Weighing some 16 tons and taking up more than 450 square feet of space
along a wall inside the accelerator lab, RESOLUT enables researchers to
fire a beam of atomic particles through a steel tube at speeds approaching
60 million miles per hour -- roughly one-tenth the speed of light -- and
then to observe the nuclear reactions that occur.
"When the beam strikes a target, the collision produces very exotic
nuclei that contain properties similar to those occurring in stars and
star explosions," Wiedenhover said. "But perhaps RESOLUT's greatest value
as a scientific instrument is its function as a mass spectrometer -- a
device that allows us to identify and study the short-lived particles
created during these miniature explosions."
Wiedenhover currently is overseeing several experiments using RESOLUT
that create, for a fraction of a second, a specific type of radioactive
nuclei that are found only in a type of exploding star known as a Type Ia
supernova.
"Type Ia supernovas result when a certain type of star known as a white
dwarf reaches a critical mass and burns through its nuclear fuel so
quickly that it suddenly explodes," Wiedenhover said. "What makes these
explosions so useful for astrophysicists is that they always release the
same amount of energy, so their peak brightness is virtually the same in
all instances. This uniform level of brightness makes Type Ia supernovas
useful as a 'standard candle' -- a gauge for measuring distances across
the universe."
Such standard candles also have helped scientists to determine in
recent years that the universe is expanding, not shrinking -- and that the
expansion is taking place at an ever-increasing rate.
"Observations of Type Ia supernovas have greatly increased science's
understanding of the workings of the universe," Tabor said. "Now, with
RESOLUT, we hope to learn even more about these gigantic nuclear
explosions -- all from the safety of a lab in a basement on the FSU
campus.
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