Technical Benefits of High Energy Physics

Technology that was developed in response to the demands of high energy physics (HEP) has become exceedingly useful to other fields of science, and thus has helped science to advance on a broad front.  Synchrotron light sources, an outgrowth of electron accelerators and storage rings, have become invaluable tools for materials science, structural biology, chemistry, and environmental science.

Accelerators are also used for radiation therapy and to produce isotopes for medical imaging.  In U.S. hospitals, diagnostic or therapeutic nuclear medicine procedures are used to help treat one third of all patients.

The World Wide Web was invented by Tim Berners-Lee in late 1990, when he was working at the European Laboratory for Particle Physics (CERN) in Geneva , Switzerland . He and Robert Cailliau of CERN were seeking a platform-independent method of communicating over the Internet the huge amounts of data generated every day in high energy physics. American high energy physicists soon established web servers at SLAC and Fermilab and developed a browser to help find information. Web use surged in the high energy physics community, and word of the powerful new communications technology began leaking out into the world at large.

The Web has created a worldwide revolution in communications and commerce. Technical benefits of high energy physics are not always in the form of equipment. Sometimes they are just new ways of doing things.  The World Wide Web is a way of finding information; in the words of Berners-Lee and Cailliau, “…a way to link and access information... as a web of nodes…” It was needed by scientific collaborations, which must share information located on many separate computers, and has proven enormously useful for other activities as well.

An important product of the DOE's HEP program is the set of talented people, trained in scientific methods and in state-of-the-art technologies.  Many of them go into careers in high-tech industries, contributing to our country’s economic strength.

Medical Applications

In U.S. hospitals, one of every three patients benefits from diagnostic or therapeutic nuclear medicine procedures (about 36,000 per day).  More than 50 diagnostic tests involve nuclear medicine and 20% of all radiopharmaceuticals use isotopes produced in accelerators.

Medical imaging techniques include Magnetic Resonance Imaging (MRI), Spiral Computed Tomography (CT), and Positron Emission Tomography (PET).   Small accelerators (cyclotrons) installed in 35 hospitals and 55 radiopharmaceutical companies produce the short-lived isotopes used in PET imaging.  About 1,000 clinical PET procedures are performed daily (250,000 annually).  Image reconstruction techniques developed for high energy physics experiments were used in CT imaging.

Superconducting magnets are used in MRI because the field must cover a large volume and must be very stable.  The development of a superconductor manufacturing industry was substantially advanced by the demands of DOE research laboratories for superconductors to be used in accelerator magnets, and the resulting industrial supply of conductor encouraged the use of superconducting magnets for MRI.  An industry leader said that the demands made by accelerator laboratories advanced by ten years the adoption of superconducting magnets for MRI.

Cancer therapy is performed with beams of electrons, photons, or protons from accelerators.  Neutrons, heavy ions, and pions have also been used to treat cancers.   A total of 30, 000 patients have been treated with proton beams since 1954, and far more have been treated with electron beams.  About 10, 000 cancer patients are treated every day in the United States with electron beams from linear accelerators (linacs).

Compact electron linacs based on accelerators developed for the Stanford Linear Accelerator Center (SLAC) and Los Alamos National Laboratory are used to sterilize syringes, gloves, and pharmaceuticals.

Synchrotron radiation from accelerators like the Stanford Synchrotron Radiation Laboratory (SSRL) at the Stanford Linear Accelerator Center (SLAC) and the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory may offer a safer way of imaging arteries (coronary angiography) by allowing injection of the contrast agent into veins instead of directly into arteries.  Synchrotron radiation is used to examine the structure of proteins, enzymes, and viruses, aiding in the design of drugs.  For example: recent studies contributed to the development of new pharmaceuticals effective in the treatment of AIDS and influenza, and crystallographers using the Brookhaven and Argonne synchrotrons solved the major structure of the ribosome, the cell’s factory for assembling proteins. 

A real time measurement and feedback system developed for ultra-precise machining needed for developing copper cells for the International Linear Collider can also be used to improve consistency of laser eye surgery by providing corneal shape feedback during the ablation process.

Industrial Applications

The use of ion beams from accelerators to embed doped layers in semiconductors is essential to the multi-billion-dollar semiconductor industry.  Ion implantation is also used to harden surfaces such as those of artificial hip or knee joints, high-speed bearings, or cutting tools by using ion beams to alloy a thin surface layer.

X-ray lithography with intense x-ray beams from synchrotron light sources like the NSLS can be used to etch microchips and other semiconductor devices.  A pattern on a mask is transferred to a photoresist coating on a wafer, achieving finer spatial resolution with x-rays than with light.  Ultimately, commercial x-ray lithography will require compact x-ray sources. 

Radiation generated by electron beams from compact linacs is used for materials irradiation, such as cross-linking a polymer to strengthen it, curing epoxies, or producing shrink film.  It is also used to remove pollutants from utility stack gas and to reduce toxic wastes to less toxic products.

Power supplies developed for accelerators are widely used in industry.   For example, reliable high power, high voltage flat-top electric pulses are needed for production of silicon wafers, food processing for extended shelf life, waste treatment, and pollution control.  One such power supply is the solid state modulator developed to power the high voltage klystrons to be used in the Spallation Neutron Source (SNS) accelerator project (see Other Applications, below). 

A compact refrigerator to produce liquid helium was developed for the DOE high energy physics program in the late 1980s by Boreas, Inc.  It eliminated the need for an external supply of liquid helium.  This type of compact refrigerator, called a “cryocooler,” is now used to cool superconducting magnets for magnetic resonance imaging (see Medical Applications, above) and for other applications, such as mass spectrometry. 

Specially shaped reflecting cones were developed to increase light collection efficiency for phototubes in high energy physics experiments.  Collectors based on these Winston Cones are now used to concentrate sunlight for solar energy systems.

Other Applications

Accelerators are used for accurate, nondestructive dating of archeological samples and art objects.  Synchrotron radiation from accelerators is finding important new applications in non-destructive trace elemental and chemical analysis on samples ranging from art objects to semiconductor surfaces. 

NASA uses accelerators for the simulation of cosmic rays, to determine the effects of this radiation on astronauts.

Accelerators have a number of defense applications, such as providing radiographic diagnostics in tests of non-nuclear weapon primaries and simulating the effects of nuclear explosions.  Accelerators may also be used to convert plutonium from dismantled weapons into a form that cannot be subverted for use in other weapons and to transmute radioactive or fissile waste (ATW) into stable isotopes or short-lived isotopes that decay to stable products.

Electron microscopy is based on electron accelerator technology and plays a major role in materials research.  It is involved in some way in more than one third of all papers published in materials science journals.

Neutrons are also used in materials science, for example, to determine the atomic scale structure of superconductors, magnetic materials, or advanced polymers.  Nuclear reactors have usually been used as the source of neutrons.  Now a new facility called the Spallation Neutron Source (SNS) is being built at Oak Ridge National Laboratory in Tennessee .  It will use a proton accelerator to produce intense pulses of neutrons whose energies can be determined by time of flight.  Six DOE laboratories have teamed to build this major new research facility.