What Are Particle Accelerators?

Fundamental parts of a particle accelerator

Particle accelerators produce and accelerate beams of charged particles, such as electrons, protons and ions, of atomic and sub-atomic size. They are used not only in fundamental research for an improved understanding of matter, but also in a plethora of socio-economic applications related to health, environmental monitoring, food quality, and energy and aerospace technologies, among other fields.

Particle accelerators can be linear (straight) or circular in shape and have many different sizes. They can be tens of kilometres long or fit in a small room, but all accelerators feature four principal components:

(1) A source which produces the charged particles;

(2) A composite device to add energy to the particles and speed them up by applying a static or oscillating electric field;

(3) A sequence of metallic tubes in a vacuum to allow the particles to move freely without colliding with air molecules or dust, which can dissipate the beam;

(4) A system of electromagnets to steer and focus the beam particles or change their trajectories before being bombarded into a target sample.

Uses of particle beams

HEALTH

Beams are used to sterilize medical equipment and produce radioisotopes required to synthesize radiopharmaceuticals for cancer diagnosis and therapy. Large accelerators can destroy cancer cells, reveal the structure of proteins and viruses, and optimize vaccines and new drugs.

RESEARCH

Some accelerators — the largest ones — are used to make sub-nuclear particles collide to advance our knowledge of the universe. Some of these accelerators are also used to produce neutrons.

ENVIRONMENT

Typically, proton beams can be used to detect trace chemical elements in the air, water or soil. For example, they can reveal the concentration and composition of the different pollutants and provide a unique signature of the air quality.

INDUSTRY

Beams can interact with the atoms of a target material — for example, to make the material more durable.

Types of particle accelerators

ION IMPLANTERS

Ion implanters are widely used in industry to, for example, make materials more resistant to damage from wear and usage. Around 12 000 ion implanters around the world help fabricate semiconductors for smartphones and solar panels. and harden metal, ceramic and glass finishes. Ion implanters can also improve the reliability of materials used for medical implants.

ELECTRON BEAM ACCELERATORS

There are almost 10 000 electron beam accelerators in operation globally. They can, for example, help make materials more durable in extreme temperatures, or resistant against chemicals. Electron beams are also used for sterilizing medical products and foods, and to disinfect sewage water. They are used widely in the automotive and aerospace industries, for machine construction, and by medical product manufacturers.

LINACS

Linear accelerators (linacs) may vary in length, from a couple of metres to a few kilometres long. Many of them are used in scientific research. Medical linacs installed at hospitals, create bursts of X-rays that are guided towards tumour cells to destroy them. There are about 1000 medical linacs operating worldwide.

CYCLOTRONS

More than 1200 cyclotrons around the world create proton or deuteron beams for medical uses. They produce radioisotopes that are used for medical imaging to diagnose and treat cancers. Many cyclotrons are located at hospitals for producing radiopharmaceuticals with short-lived radioisotopes.

SYNCHROTRONS

The more than 70 synchrotrons worldwide are the giants among particle accelerators. They are used for scientific research and help us understand the fundamental laws of our universe. Scientists use synchrotrons to study chemistry, biomedicine, natural and cultural heritage, the environment, and much more.  

ELECTROSTATIC ACCELERATORS

Electrostatic accelerators, notably tandem accelerators, are less expensive, and scientists use them to investigate material properties, monitor the environment, support biomedical research, study cultural heritage objects, and more. Experts expect the current 300 machines worldwide to grow in number over the coming years.

Today, there are more than 20 000 accelerators in operation worldwide.