ATLAS upgrade allows scientists to reach even further for the stars
(Download printer-friendly PDF version.)
ARGONNE, Ill. (June 8, 2007) — With an eye toward learning more about
the elements that make up the universe and everything in it, Argonne scientists
have reached the latest milestone in an upgrade of ATLAS, a leading facility
for nuclear structure research in the United States.
ATLAS — which stands for Argonne Tandem Linear Accelerator System — provides
beams and experimental instruments for nuclear reaction and structure research
to scientists from the United States and around the world. In 2006, ATLAS had
436 active users. The upgrade will give the facility more versatility and open
up new areas of scientific inquiry.
ATLAS is the world's first superconducting linear accelerator for heavy ions
and is used by researchers to study the properties of the nucleus, the core
of the atom, representing 99 percent of its mass.
Every element in the universe has its origins in the stars and explosions
that started billions of years ago and are still going on in stars today. "If
we want to understand these elements, if we want to understand the very material
we are made of, we need to find a way to study these nuclei," said Robert
Janssens, acting director of Argonne's Physics
Division.
The ATLAS upgrade is called CARIBU, which stands for Californium Rare Ion
Breeder Upgrade. It will provide for the acceleration of neutron-rich fission
fragments from a californium-252 source to study neutron-rich nuclei, particularly
those responsible for the production of a large fraction of the heavy elements
in the universe. The upgrade will give researchers access to regions of the
nuclear landscape – areas of unstable isotopes – that have been beyond the
reach of current physics research facilities. The project is led by Project
Manager Richard Pardo and Technical Director Guy Savard of the Physics Division.
According to Janssens, about 50 percent of the elements in the universe heavier
than iron are created in this area of unstable isotopes. "We've only seen
half of the isotopes that we believe actually exist," he said. "We
will have the first peek at many new ones.”
A critical component of CARIBU is a “gas catcher cell” developed by a team
led by Guy Savard. Researchers recently passed a significant milestone in the
design and performance of this device at the intensities needed for the upgrade.
The gas catcher provides a new way to generate intense beams of short-lived
radioactive isotopes by allowing researchers to manipulate fragments from a
fission source into a coherent beam.
“No one else in the world has demonstrated the gas stopping technology to
within orders of magnitude of the Argonne results,” said Argonne physicist
Don Geesaman. "CARIBU will make about 400 new beams available that we've
never been able to accelerate before. We're going to have beams no one else
has."
Researchers are now preparing to install the gas catcher device. And while
the technology has been demonstrated in experiments, using it in the operation
of CARIBU/ATLAS will allow physicists to test the technology in what Geesaman
and Janssens call "battle conditions."
“It's extremely challenging technology,” said Geesaman. “There is no place
but Argonne that could come close to doing this project on this budget. It's
a beautifully sweet fit to our technological talents and the equipment we have.” He
adds that the research carried out at the Argonne facility will be highly complementary
to other physics efforts worldwide.
The physics research conducted at the facility may seem esoteric to some,
but Geesaman stresses that "our experience shows there are significant
applications that can come out of this. For example, measurements we can make
on the decay heat of particular fission products are important for people designing
advanced fuel cycles.” Other future applications also may include new medical
applications and insights into materials that could lead to the development
of, for example, better disk drives.
But, like all physicists, both Geesaman and Janssens are ultimately driven
by the desire to learn how nature works at the most fundamental level. "The
nucleus is the core of matter. It is the fuel of stars,” said Janssens. “Carl
Sagan said we're all stardust, but you know, it's true. Without the stars,
we wouldn't be here."
While CARIBU is important for ongoing research at ATLAS, it could also be
crucial for the next level of physics research in the United States. That
next step is the construction of an Advanced Exotic Beam Laboratory, a project
the U.S. scientific community has labeled one of its highest priorities. It
is expected that a request for proposals for this new facility will be made
in 2008. Argonne's experience with CARIBU will help researchers learn where
to focus their attention when they write their proposal for bringing the facility
to Argonne.
The cost of CARIBU is $4.75 million, with $3.6 million of that total coming
from new funding and the rest coming from redirection of ATLAS funds. Funding
comes from the U.S. Department of Energy's Office of Nuclear
Physics. Coupled
to CARIBU are other facility upgrades including the installation of new classes
of accelerating structures in an energy upgrade and the installation of a new
experimental device called HELIOS – Helical Orbit Spectrometer – an instrument
designed to make optimal use of the new CARIBU beams. The project is scheduled
to be completed in the second quarter of fiscal year 2009.
Argonne National Laboratory seeks solutions to pressing national problems in science and technology.
The nation's first national laboratory, Argonne conducts leading-edge basic
and applied scientific research in virtually every scientific discipline. Argonne
researchers work closely with researchers from hundreds of companies, universities,
and federal, state and municipal agencies to help them solve their specific
problems, advance America 's scientific leadership and prepare the nation for
a better future. With employees from more than 60 nations, Argonne is managed
by UChicago
Argonne, LLC for
the U.S.
Department of Energy's Office
of Science.
— Donna Jones Pelkie
For more information, please
contact Steve McGregor (630/252-5580 or media@anl.gov)
at Argonne.
|