1. Particle Accelerators for Research and for Medicine
Prof. Ted Wilson (CERN and Oxford University)
based on the book:
ISBN
This talk:
I am Ted Wilson and since I retired from designing a large number of CERN’s accelerators (from SPS through the Antiproton Accumulator. LEP and the initial design of LHC) I have been a visiting professor teaching postgraduate physics Students at this University – The John Adams Institute.
Let me ask you a question : are you in a second or thirdyear the physics course?
Whichever – my advice – based on my undergradute experience. Don’t be seduced by the social life- work hard to avoid looking back with the regret. Don’t end up saying “If only .. then I would have got a first or upper second and enjoyed thrill of doing research instead of the many mundane jobs the world offers.
The other advice I have is not to be too impressed by very academic subjects like theoretical physics . If you are not careful Oxford and its academic crucible will fool you
Choose a technical activity or applied science where you will be able to look back and say (when you are my age) “my work did something for living human beings”. Some of the accelrators I will tell you about today offer that alterntive and are just as challenging as LHC.
But not every accelerator has been built for particle physics, and accelerators for applications other than high-energy now outnumber the large atom-smashers by two orders of magnitude. The speaker will concentrate on some of the more practical uses of accelerators that directly benefit mankind, including medical diagnosis and therapy.

2. The Large Hadron Collider (LHC)
The LHC, at CERN, is the primary tool
to which high-energy physicists used to discover the Higgs particle. The machine is 28 km
in circumference.
Ofcourse the machine of the moment is no doubt the LHC. I played my humble part in its design analysing the dynamics of particles circulating aroung the ring under the influence of non-linear fields.

3. CERN Control Centre - Layout
These are the young people who run it – I taught most of them.

4. days... 3.5 TeV collisions on March 30th
These are the old people who were ther to see it work!

5. An “exploded” diagram of the ATLAS detector, for the LHC.
The physics apparatus of the LHC included huge detectors. Designed and built by consortia of Univerities form around the world. The names on the per run into thousands. CERN’s cantines are bursting with their excitement and youth.
An “exploded” diagram of the ATLAS detector, for the LHC.

6. Cyclotron r + Magnet Vdee~ At all radii particles cross
acceleration gap at same moment !
Another kind of machine, invented by Lawrence in 1930’s and used since for the benifit of us all.
Now they are produced for hospitals in their scores.

7. Spect diagnosis Cyccotrons make isotopes for medical diagnosis
Early imaging techniques mainly used thallium - 201, gallium-67, iodine-123 and indium-111. These isotopes emit single photons and have half-lives of the order of days so that they may be carried to a hospital. The camera which records the pattern of emitted radiation is rotated about the patient to digitize images from a number of directions to reconstruct the three dimensional shape of the source of the photon emission. The same computational algorithms that allow us to produce a three dimensional picture of an organ from multiple x-ray views (CAT scan) are used. This technique is called Single Photon Emission Computed Tomography (SPECT). Resolution achieved is typically of the order of 1 cm.

8. Linacs – an idea waiting for a technology
Luis Alvarez
Ed Ginzton
Another kind of accelrator used for medicine and other important things. The Linac.
Linacs had to wait 15 years for this technology – the S-band Klystron
The high powered klystron was invented, during WWII, by
The Varian Brothers and Ed Ginzton. Using it, Bill Hansen
invented the electron linac. A succession of machines at
Stanford culminated in the two-mile accelerator, SLAC,
led by WKH Panofsky. That machine made many important
high-energy physics discoveries and then became the
injector for PEP and PEP II, and now has become the
LCLS.
In the years before World War II, Alvarez was particularly prolific, having discovered the capture of electrons in beta decay (K-capture), determined the stability of He3, and measured, with Felix Bloch, the magnetic moment of the neutron.
With the start of World War II, Alvarez went to the Radiation Laboratory at MIT, where he worked on ground-based radars. He invented the VIXEN method for detecting enemy submarines and, perhaps most importantly, Ground Controlled Approach radar, which is the basis for all such systems, in use to this day for the safe landing of airplanes throughout the world. Shortly later, Alvarez went to Los Alamos, where he developed the shock wave method of measuring the strength of nuclear explosions.
Engines of Discovery

9. Cancer Therapy Machines
A modern system for treating a patient with x-rays produced by a high energy electron beam. The system, built by Varian, shows the very precise controls for positioning of a patient. The whole device is mounted on a gantry. As the gantry is rotated, so is the accelerator and the resulting x-rays, so that the radiation can be delivered to the tumor from all directions.
Electrons are accelerated in a linac and then shot into a metallic target to produce xrays. The microwave linacs that are to be found in many hospitals range in energy from 4 to 22 MeV. The linac, followed by a vertically deflecting magnet system that can turn the beam through 90 degrees, is small enough to rotate about the patient, forming a rather simple form of gantry
Engines of Discovery

10. The Synchrotron
Cyclotrons became huge and particles lost synch as they became relativistic.
Batch acceleration allowed one to use a fixed radious – the rim
The synchrotron and its colliders became the workhorse of particle physics leading to the LHC but

11. A drawing showing the Japanese proton ion synchrotron, HIMAC
A drawing showing the Japanese proton ion synchrotron, HIMAC. The facility consists of two synchrotrons, so as to maintain a continuous supply of ions (or protons) to the treatment area. The pulse of ions is synchronized with the respiration of the patient so as to minimize the effect of organ movement.
Synchrotrons (and cyclotrons) of about 250 MeV - reach any internal organ.
Advantage of protons over x-rays and neutrons is that the radiative energy is deposited at a particular depth within the person, in a thin layer called the Bragg peak.
Ions also deposit their energy in the Bragg peak at the site of the tumor but the density of the deposited energy increases as the square of the atomic number, making heavier ions even more effective than protons “taking out” large sections of DNA, which cannot be repaired.
The synchrotrons used at Loma Linda in Los Angeles; and the Heavy Ion Medical Accelerator Facility (HIMAC) in Japan, were the first to follow the early hadron work at Harvard and Berkeley.
Another ion installation is at the GSI Laboratory in Germany.
Much European work is based upon the pioneering work of the “Proton and Ion Medical Machine Study” (PIMMS) carried out at CERN by a working group with members from various institutes.
The Heidelberg Ion Therapy Centre (HICAT) —aimed at treating its first patient in The second European centre, an initiative of Ugo Amaldi, is the Centro Nazionale di Adroterapia Oncologica, now being built in Pave, Italy.
Other carbon ion centers are under consideration, such as the Med-Austron in Wiener Neustadt, ETOILE in Lyon, ASCLEPIOS in Caen, and a centre proposed by the Karolinska Institute in Sweden.
(FFAG) cyclotrons, with their compact ring of components, are now being considered for this purpose.
Meanwhile a joint venture between the Cockcroft and Adman Institutes is studying the use of FFAG’s for accelerating ions
Engines of Discovery

12. First electron synchroton
The first synchroton– where to look for synchrotron radiation.
This 300 MeV electron synchroton at the General Electric Co. at Schenectady, built in the late 1940s. The photograph shows a beam of synchrotron radiation emerging.
Engines of Discovery

13. Synchrotron Radiation Sources
There are more than 50
synchrotron radiation facilities in the world.
In the US there are machines in Brookhaven
(NSLS), Argonne (APS), SLAC: SPEAR and
the LCLS, and at LBL (ALS).
Given the great success of the large number of second generation facilities, enthusiasm developed to go to even shorter wavelengths; i.e., to even more energetic (“harder”) x-rays which reveal even more detail. This meant that the facilities had to store even higher energy electrons and thus occupied a larger “footprint.” These facilities exploited the very latest in machine lattice design and the latest insertion devices to produce very intense x-ray beams. The first of this new generation was the European Synchrotron Radiation Facility built at Grenoble (France), which stores 6 GeV electrons (see Fig. X.3).
This synchrotron storage ring is higher in energy than second generation sources. A higher energy moves the spectrum of radiation towards shorter wavelengths from UV, through VUV towards x-rays. (See the sidebar on Wavelength frequency and photon energy). At the same time the total power of the radiation increases and to optimize this to match the capability of the RF system to replace it the machine has a larger radius. One of the side benefits of the larger radius is that more tangential beam lines and more users can be accommodated around the circumference. We see from Figure X.3 that the machine is on an island at the confluence of two rivers sharing the site with a neutron diffraction facility which can complement the synchrotron radiation patters of electron distribution with its own studies of the nuclear structure of crystals.
This intricate structure of a complex protein molecule structure
has been determined by reconstructing scattered synchrotron radiation

14. Linac Coherent Light Source and the European Union X-Ray Free Electron Laser (Fourth Generation)
FELs, invented in the late 1970’s at Stanford are now becoming the basis of major facilities in the USA (SLAC) and Europe (DESY) .They promise intense coherent radiation. The present projects expect to reach radiation of 1 Angstrom (0.1 nano-meters, 10kilo-volt radiation)
FEL for a fourth generation source
What is an FEL
Invented by John Madey
Beam of tightly bunched electrons, accelerated in a linac, passes through a wiggler
The radiation emitted in the bends remains in phase with the bunches and, reacting back on the bunches, causes them to bunch even more sharply, enhancing the brilliance of the radiation.
Like a laser the light is coherent, adding up in amplitude so that double the amplitude produces four times the power.
“Self Amplified Spontaneous Emission” (SASE),
Pioneered by Claudio Pellegrini
It is effectively an amplifier for x-rays but one cannot feed x-ray radiation into the wiggler; there simply are no sources powerful enough.
This method is called “Self Amplified Spontaneous Emission” (SASE)
The first few wiggles produce some x-ray “noise,” enough for the rest of the wiggler to amplify. ↓
Engines of Discovery

15. ↓ Electrons 14 GeV Peak current > 1000A Transversely < 0.1 mm
1012 photons
0.15 < l < 1.5 nm
Pulse: 100 femtoseconds
down to 100 attoseconds
Rate 120 Hz
1000 to times brighter
than third generation
Cost M$ 300
The SLAC site showing its two-mile long linear accelerator, the two arms of the SLC linear collider, and the large ring of PEPII. This is where the LCLS will be located.
X-RAY FEL Projects Abound
The SLAC Linac Coherent Light Source (LCLS)
European Union X-ray Free Electron Laser (EU XFEL) at DESY in Germany,
SPring-8 Compact SASE Source (SCSS) in Japan
14 GeV electrons from the original SLAC linear accelerator.
Electron pulses of high peak current (more than a thousand amperes and transversely less than a tenth of a millimeter),.
. x-ray pulses 10**12 photons of wavelength 0.15 to 1.5 nm,
pulse duration of 100 femtoseconds down to 100 attoseconds
pulse rate of 120 Hz.
Will beat average brightness the present third generation light sources by a factor between 1,000 and 10,000.
Dental x-ray installation would only have a “brightness” about ten million times weaker!
Due for completion by the end of 2008, will cost $300 million. ↓
Engines of Discovery

16. Spallation Neutron Sources (SNS)
1GeV protons
mean current 1 mA
= 1.4 MW of power
In a
0.7 microsecuond burst
Cost is about 1.5 B$
Other synchrotons
Two spallation sources, a synchrotron called ISIS at the Rutherford-Appleton Laboratory in the UK and a cyclotron driven spallation source at PSI in Switzerland, share the honors for the most powerful sources in operation.
An even larger spallation source (the SNS) has just been completed in the US, at Oak Ridge and its design specification it will produce:
an average proton beam current of 1.4 mA
at 1 GeV will deposit 1.4 MW of power in the target and its surroundings.
each proton pulse on target is 0.7 microseconds long, short enough to provide excellent wavelength tagging of each neutron,
The cost of the SNS — about 1.5 B$ — is comparable with the big machines of particle physics.
Future Sources
While serious consideration of a similar spallation source has been going on for many years in Europe. The Japanese are constructing a large accelerator complex at the JAERI, Tokay site, the major part of which is a spallation source. In 2005 the Chinese initiated a design study for their own spallation source (the CSNS).
An overview of the Spallation Neutron Source (SNS) site at Oak Ridge National Laboratory.
Engines of Discovery

17. High temperature superconductor
Picture revealed by neutron scattering
Crystal structure of the 90K YBa2Cu3O7 superconductor

18. Inertial confinement
Energy research - Accelerators for Heavy Ion Fusion
The European Heavy Ion Fusion project using induction linac
Here is the US HI Fusion Project:
The beam consists of 3 GeV heavy ions in a 4 kA pulse, 10 ns long
A typical configuration starts with a multiple-beam ion source (more than 100 beams) and an injector that accelerates a 20 microsecond pulse of 1 A to 2–3 MeV.
There follows acceleration
At 3 GeV there is longitudinal compression that results in a beam of 200 A/beam and a pulse of 200 ns.
Then the beam is neutralized and focused both longitudinally and transversely so as to achieve the desired beam for imploding a pellet.

19. Proton Drivers for Power Reactors
A linac scheme for driving a reactor. These devices can turn thorium into a reactor fuel, power a reactor safely, and burn up long-lived fission products.
Proton Drivers for Power Reactors (Energy Amplifier)
Reactor that could not remain critical without the accelerator beam.
No danger of a reactor meltdown due to a cooling failure or unplanned release as at Chernobyl
Detailed studies, including experimental work, have been made in Europe to design such a reactor burning thorium instead of uranium.
Thorium, cannot produce dangerous, long-lived transuranic isotopes such as plutonium.
Also achieves the “burning up” of longlived nuclear wastes.
The idea occurred to the Los Alamos group, and also a group in CERN under the direction of Carlo Rubbia
A Linac scheme from Los Alamos
Engines of Discovery

20. Oxford/LBNL Plasma-Laser Experiments:
Guiding achieved over 33 mm:
Capillary 190 um
Input laser power 40 TW
Peak input intensity > 1018 W cm-2
Plasma: 3 × 1018 cm-3
Spot size at entrance 26 μm
Spot size at exit 33 μm
Entrance
Exit
Plasma channel formed by heat conduction to capillary wall.
E = (1.0 +/-0.06) GeV
ΔE = 2.5% r.m.s
Δθ = 1.6 mrad r.m.s.
Oxford/LBNL Plasma-Laser Experiments
It was John Dawson (see sidebar for Dawson) with Toshi Tajima (1979) first suggested the use of plasmas. Excitation of a plasma electrostatic wave by means of the laser and, then, use of the plasma wave to accelerate particles. The plasma wave is longitudinal andis not one moving at the velocity of light. The efficiency of this process, the required stability of the plasma, the injection of electrons to be accelerated, the staging of sections, and propagation for long distances are subjects that have been addressed, with considerable success, in the last decades.
In the Plasma Beat Wave Accelerator (PBWA) two laser pulses of frequency very close to each other, but with a difference frequency just equal to the oscillation frequency of a plasma electrostatic wave, are fed into plasma. Typical energy gains of a few tens of MeV have been achieved in tests.
In the LWFA the plasma wave is excited by a shock. A variation is Self-Modulated Laser Wakefield Accelerator (SMLWFA). One of the most dramatic results has been the production at LBL of 1 GeV electrons in plasma of only one millimeter in extent. This is an acceleration gradient of 200 GeV/m (which might be compared to that proposed for the ILC of 35 MeV/m; i.e., an increase of a factor of 6,000).RAL have similar results
To build an accelerator from an intense laser beam, one has to guide the laser beam for long distances. This is in conflict with the spreading called the ­. Effort into developing plasma channels that, rather like optical fibers, have this property.
One must look to university departments and in collaboration with laboratories.
W. P. Leemans et al. Nature Physics (2006)
Butler et al. Phys. Rev. Lett (2002).
D. J. Spence et al. Phys. Rev. E (R) (2001)
Engines of Discovery

21. Neutrino experiments Kamiokande Solar Neutrino Problem Super K K to K
Gran Sasso
Minos and NUMI
Super Beams
Neutrino Factories
Muon Colliders
Kamiokande
This very large underground detector, located in the mountains of Japan. Many very important results have come from this facility that first took data in The facility was instrumental in solving “the solar neutrino problem.
For Nuclear physics Neutrino Experiments - Kamiokande
Neutrinos oscillate from one type to another over huge distances
This implies that they have mass, (cannot be explained by the Standard Model).
Experiments use neutrinos produced by the decay of particles produced by proton beams from existing synchrotrons, but people are thinking of
“Super beams” from even more powerful accelerators.
“Beta beams” of accelerated radioactive species that produce neutrinos from their beta decay.
“Neutrino factory”: a storage ring where muons decay into a beam of neutrinos.
Engines of Discovery

22. Basis of muon collider Engines of Discovery
New big machines for particle physics Neutrion Factory and Muon Colliders
Muons are leptons, like electrons have the advantage of an unambiguous point-like structure.
The muon will not radiate significant amounts of synchrotron light even at the energies at which the present generation of proton colliders operate.(an alternative to the linear collider)
The muon decays in about a microsecond But, the time and distance it travels before it decays increases in proportion to the energy. `At 100 GeV or more, the colliding beams will exist for about one millisecond in the laboratory reference frame: long enough to see some events.
The spread in angles of the muons is far larger than the acceptance of most accelerators (an exception is discussed below) and hence the muons must be “cooled.”
The only possible method is ionization cooling.
In the overall process of losing energy (momentum) by ionizing the atoms of an absorber — and then being reaccelerated in the forward direction — particles take up new trajectories closer to the axis of the beam.
A large international cooling experiment, the Muon Ionization Cooling Experiment (MICE), is under development at the Rutherford-Appleton Laboratory in England to prove it.
Engines of Discovery

23. The International Linear Collider (ILC)
The book describes this as a case study on how to prepare new giant projects. Members of many teams from all over the world — some physicists, some engineers; some using pure theory, others building prototype and test stands — have worked for many years.
A managerial structure embodying the collaboration of all the particle physics institutes that were previously working on TESLA, NLC and JLC has been set up.
It has been decided to follow the superconducting path (easy technical decision)
Proceed with the fascinating exercise of choosing a place to put the new machine among the continents of the world. (difficult political decision)
Engines of Discovery

24. I have not mentioned Sterilisation Chip manufacture
Art and archaeology
National Security
Surface treatment
Etc. etc….

25. Accelerators bringing nations together
The King of Jordan discussing with scientists the Sesame Project, which will be located in Jordan and available to all scientists.
Accelerators bringing nations together
The last chapter – Mainly for the Young
Just as CERN was formed (thanks to UNESCO) to heal the scars of a European war, so Sesame
SESAME is short for “Synchrotron light for Experimental Science and Applications in the Middle East”. It is a bold and imaginative venture involving Bahrain, Egypt, Islamic Republic of Iran, Israel, Jordan, Pakistan, Palestinian Authority, Turkey and the United Arab Emirates. It may seem to some to be quite improbable that these states, many of whom have an ongoing history of disagreement and conflict, could agree on any common enterprise - but they have. Just as building a common accelerator facility at CERN united the recently warring factions in Europe in 1953, the proponents of SESAME have a vision that SESAME may play the same role for the Middle East.
Engines of Discovery

26. Conclusion
I have sketched for you some of the likely future projects of accelerator physics future. Perhaps, the development of accelerators was a passing moment in the history of mankind, but it is much more likely to be an activity that will continue, producing devices not only for physics, but for an ever increasing catalogue applications enriching our everyday lives.
You have learned in lectures all about the many kinds of accelerators, electrostatic, cyclotrons, linacs, synchrotrons, colliders etc. – the different particles hadrons and leptons that are accelerated. You will find all this explained in words in our book but also we have tried to explain
how each idea grew from noise
what kind of people were those that made the discoveries.
The history of accelerators mirrors the development of the technologies of the 20th century from invention of radio to superconductivity.
If you wanted to chart the technology of the 19th century you might well look at how engineers made bridges and steam engines railways and early motor cars

27. Thank you for your attention.

28. The race to high energies
Rutherford fired the starting pistol
Rutherford fired the starting pistol
At the Royal Society in 1928 he said
“I have long hoped for a source of positive particles more energetic than those emitted from natural radioactive substances”.
At the Royal Society in 1928 he said
“I have long hoped for a source of positive particles more energetic than those emitted from natural radioactive substances”.
Engines of Discovery

29. Wideroe invented the Linac
Particle gains energy at each gap
Lengths of drift tubes follow increasing velocity
Spacing becomes regular as v approaches c
Someone who was inspired by Rutherford was a Norwegian – Rolf Wideroe. A prolific inventor, he is variously credited with the invention of the betatron, the linac, the synchrotron, and storage rings for colliding beam and certainly he built the first pair of linac drift tubes for his Dr. Ing. thesis at Aachen in 1927.
During the war years he had indeed been working in Berlin on betatrons which he was told would serve as a compact X-ray source in field hospitals. (Actually, The Nazi leadership hoped to use it to blind bomber pilots.) He agreed to do this when promised the release of his brother, Viggo, who had been imprisoned by the Nazis on suspicion of spying in Norway.
Can you imagine why this device had to remain (on the shelf) for 15 years before it could be used.
His many other claims as an innovator, though substantiated by patents were often hidden from the free world of science by the clouds of war and had to be re-invented , either independently or subsequently by others. It does seem clear however that his enthusiasm for storage ring colliders prompted his good friend Touschek, himself imprisoned by the Nazis, to build the first such device after the war.
Engines of Discovery

30. The 60-inch cyclotron. The picture was taken in 1939.
He built many machines for medicine encouraged by his brother John who was a doctor – irradiated his grandmother was a master of fund-raising and publicity. Berkeley University president is reported as complaining that “Instead of a University with a Cyclotron Berkeley has become a cyclotron with a University attached. People told him relativity would limit energies to 30 MeV but he just pushed on and built a 184 inch machine.
The 60-inch cyclotron. The picture was taken in 1939.

31. The Dual Axis Radiological Hydrodynamic Test Facility This device is devoted to examining nuclear weapons from two axes rather than just one. This reveals departures from cylindrical symmetry which is a sign of aging which can seriously affect performance
Induction Linacs
The Dual Axis Radiological Hydrodynamic Test Facility This device is to examine nuclear weapons from two axes to reveal departures from cylindrical symmetry which is a sign of aging.
Next came very successful application of induction accelerators, also associated with weaponry, has been to develop intense pulses of x-rays for studying the implosion process of nuclear weapons. The FXR at Livermore was located at their remote “site 300” and, when completed in 1982, produced 3,000 A of 18 MeV electrons (see Fig XIV.3). This machine, beautifully built and, like ETA and ATA, based upon the ERA induction linac technology, has been very useful for flash radiography. In the early 1990s FXR was followed by the Dual-Axis Radiographic Hydrotest Facility, DARHT: a machine constructed at Los Alamos for the same purpose. Under the seemingly innocent name of the Stockpile Stewardship Program it became important to check if nuclear weapons are no longer cylindrically symmetric. This might be due to rust spot developing on one side of the weapon, or simply because it had been stored on one side for decades. A second axis to DARHT has therefore been constructed to find such asymmetries and this facility was run-in during the first years of this centur
The induction accelerator, FXR, at Lawrence Livermore, to study the behavior of the implosion process in nuclear weapons

32. Ions Left is the phase diagram for the quark-gluon plasma
IONS - The last 80 years of nuclear physics has mainly been devoted to studies of nuclear properties using accelerated beams of stable isotopes. The result is a detailed understanding of nuclear behavior which has had practical application in the fields of nuclear medicine, nuclear power and weaponry.
The Bevalac in Berkeley was used to study ions over the full range of the periodic table colliding with fixed targets at GeV energies.
Later this study was extended at the AGS, in Brookhaven, and then at the SPS in CERN.
Higher energies would allow study of conditions similar to that during the Big Bang at the start of the universe.
Once freed in a higher energy collision they could move throughout the nucleus forming what is called a quark-gluon plasma a new and previously unobserved state of matter. It would be similar to conditions in the big bang at the start of the universe. It may be created by colliding ions: gold on gold (for example).
This of course is the aim of RHIC at Brookhaven and the acceleration of ions in the LHC.
Left is the phase diagram for the quark-gluon plasma
Right is gold-gold collision in RHIC
Engines of Discovery

33. Unstable Isotopes and their Ions
The Rare Isotope Accelerator (RIA) scheme. The heart of the facility is composed of a driver accelerator capable of accelerating every element of the periodic table up to at least 400 MeV/nucleon. Rare isotopes will be produced in a number of dedicated production targets and will be used at rest for experiments, or they can be accelerated to energies below or near the Coulomb barrier.
Unstable Isotopes
The next major project that nuclear physicists plan is an accelerator of radioactive species of very short half-life — the so called non-equilibrium nuclei.
Beams of these rare species have already been produced and studied at the ISOLDE facility at CERN, the Bevalac at LBL, and at the superconducting cyclotron at Michigan State University, but now new facilities of expanded capability are called for.
Different methods of producing radioactive beams
There are four projects of this type.
The first, already completed, is the Radioactive Isotope Beam Facility (RIBF) at RIKEN, Wako, in Japan;
the second, under construction, is the Facility for Antiproton and Ion Research (FAIR) at GSI, Darmstadt in Germany;
the third is SPIRAL2 at GANIL in Caen, France;
and the fourth is the Rare Isotope Accelerator under consideration in the US.
The heart of the facility is composed of a driver accelerator capable of accelerating every element of the periodic table up to at least 400 MeV/nucleon. Rare isotopes will be produced in a number of dedicated production targets and will be used at rest for experiments, or they can be accelerated to energies below or near the Coulomb barrier.
Engines of Discovery