The Argonne Tandem Linac Accelerator System (ATLAS) is a
U.S. Department of Energy scientific user facility at
Argonne National Laboratory. ATLAS is the first
superconducting
Superconductivity is a set of physical properties observed in certain materials where electrical resistance vanishes and magnetic flux fields are expelled from the material. Any material exhibiting these properties is a superconductor. Unlike ...
linear accelerator
A linear particle accelerator (often shortened to linac) is a type of particle accelerator that accelerates charged subatomic particles or ions to a high speed by subjecting them to a series of oscillating electric potentials along a linear ...
for
heavy ion
High-energy nuclear physics studies the behavior of nuclear matter in energy regimes typical of high-energy physics. The primary focus of this field is the study of heavy-ion collisions, as compared to lighter atoms in other particle accelerat ...
s at energies in the vicinity of the
Coulomb barrier
The Coulomb barrier, named after Coulomb's law, which is in turn named after physicist Charles-Augustin de Coulomb, is the energy barrier due to electrostatic interaction that two nuclei need to overcome so they can get close enough to undergo a ...
and is open to scientists from all over the world.
The ATLAS accelerator at Argonne should not be confused with the
ATLAS experiment
ATLAS is the largest general-purpose particle detector experiment at the Large Hadron Collider (LHC), a particle accelerator at CERN (the European Organization for Nuclear Research) in Switzerland. The experiment is designed to take advantage of ...
at the
Large Hadron Collider at
CERN.
How ATLAS works
Ions are generated from one of two sources: the 9-MV electrostatic tandem
Van de Graaff accelerator or the Positive Ion Injector, a 12-MV low-velocity
linac
A linear particle accelerator (often shortened to linac) is a type of particle accelerator that accelerates charged subatomic particles or ions to a high speed by subjecting them to a series of oscillating electric potentials along a linear be ...
and
electron cyclotron resonance
Electron cyclotron resonance (ECR) is a phenomenon observed in plasma physics, condensed matter physics, and accelerator physics. It happens when the frequency of incident radiation coincides with the natural frequency of rotation of electrons in m ...
(ECR) ion source. The ions are sent from one of these two into the 20-MV 'booster' linac, then to the 20-MV 'ATLAS' linac section.
The ATLAS linac is constructed with seven different superconducting resonator designs, each one creating an electromagnetic wave of a different velocity. The ions in the ATLAS linac are aligned into a beam which exits the linac into one of three experimental areas. The experiment areas contain
scattering chambers,
spectrometers and spectrographs,
beamlines, a
gamma-ray facility, and
particle detectors.
In 2009, Argonne added a system called CARIBU (Californium Rare Ion Breeder Upgrade) to ATLAS. The system is capable of generating beams of rare isotopes.
ATLAS has since received additional upgrades with two enhancements: The Electron Beam Ion System (EBIS), which enables radioactive beams to match the accelerating structures by increasing the ion beam’s positive charge, and the Argonne In-Flight Radioactive Ion Separator (RAISOR), which helps to improve beam purity by separating out specific isotopes. The enhancements of ATLAS with EBIS and RAISOR help scientists probe the structures of exotic elements, study the nature of the nuclear forces, and better understand the production of elements in stars and supernovae.
What ATLAS is for
The energy levels of the ions produced by ATLAS are ideal to study the properties of the
nucleus. Specifically, scientists use ATLAS to understand reactions between nuclei from very low energies (typically encountered in burning stars) to the very highest energies (encountered soon after the Big Bang). Nuclei with specific properties can be studied to understand fundamental interactions.
What is ATLAS made of
Niobium is the primary metal used to construct the tube
in the individual in-line resonators. Niobium is used because it is relatively cheap, yet it is a
Superconducting, superconductor at relatively high temperatures. Niobium has poor malleability, which makes it difficult to construct the shapes needed for the resonators. The machinists working at ATLAS are some of the only people in the world able to work with niobium to the degree necessary for construction and repair of the ATLAS parts.
[
]
Target areas
*
Atom Trap at ATLAS
*
Canadian Penning Trap Mass Spectrometer
*
Enge Split Pole Spectrograph
*
Fragment Mass Analyzer
*
Gammasphere
*
Helical Orbit Spectrometer (HELIOS)
*
Large Scattering Chamber
See also
*
Tandem Accelerator Superconducting Cyclotron (TASCC)
References
*
*
{{authority control
Argonne National Laboratory
Nuclear research institutes
Particle physics facilities