The most common type of particle accelerator is a linear electron accelerator, which fires particles in a straight line, making them useful for the intense, targeted beams needed in cancer treatment.

Particle accelerators propel matter toward small targets at high speed

Devices like cathode-ray tube televisions were once basic particle accelerators, but modern ones, such as the Large Hadron Collider, use massive magnetic fields and circular tunnels to achieve energies high enough to recreate the conditions just after the big bang.

Learn about five of the largest particle accelerators on Earth, which, as of 2026, are led by the Large Hadron Collider at the European Organization for Nuclear Research.

More than 97% of the world's particle accelerators are used for commercial purposes

Only a few hundred of the over 30,000 particle accelerators worldwide are used for research. Most are involved in medical imaging and treatment, food sterilization, semiconductor processing, cargo screening, and radioisotope production. They're also used to modify the properties of polymers.

At the Large Hadron Collider, protons are accelerated so close to the speed of light that they would lag behind a laser by just 10 feet after 14 minutes of travel.

Although built from 1996 to 2008, the Large Hadron Collider relies on accelerators built starting in 1954 to help bring protons to 99.9999991% the speed of light—about 2.73 million football fields per second.

Cyclotrons move particles in spiral paths of increasing radius

After particles are injected into the center of the device, an alternating electric field and a constant magnetic field energize the particles as they spiral outward toward a target. Cyclotrons are common in hospitals that perform molecular imaging, which relies on radioactive components that decay within hours.

Electron accelerators are used to create X-ray lasers

In an X-ray free-electron laser, electromagnetic fields are used to accelerate and move electrons in wiggling patterns, causing them to emit synchronized, high-energy X-rays. This resulting light beam can strike targets up to 120 times per second to create movies of changing molecular structures and phenomena.

The first circular particle accelerator was narrower than the average cereal bowl

The 1939 Nobel Prize in physics was awarded to Ernest Lawrence for inventing the cyclotron. By comparison, the Large Hadron Collider is 5 miles in diameter and is the largest cryogenic system in the world, cooling its electromagnets to temperatures colder than those found in outer space.

As of 2023, the world's smallest particle accelerator is smaller than a penny

The prototype is an example of a photonic accelerator, which utilizes tiny lasers to accelerate electrons rather than relying on oscillating electromagnetic fields to move them. It can deliver about 1 electron per second with energies equivalent to those found in cathode-ray tube televisions.

Particle beams can be used to alter the surface properties of artificial joints

Surface hardening and embedding specific elements or coatings can improve the biocompatibility and bone tissue integration of these implants. Particle accelerators are significant sources of the radioisotopes needed in medical diagnostics, and microwave linear accelerators are used in the majority of cancer irradiation treatments.

Particle accelerators allow physicists to create controlled nuclear experiments

Before the 1930s, scientists relied on naturally radioactive substances to learn about atomic nuclei. The first atom was split in 1932 when John Cockcroft and Ernest Walton fired a beam of accelerated protons at a lithium atom, producing alpha radiation.

Explore the components of the linear particle accelerator at Los Alamos

Located at the site of bomb design and development for the Manhattan Project, LANSCE features an injector system for hydrogen ions, a series of tanks with alternating electric fields for proton acceleration, and an isotope production facility that creates radioisotopes for medical treatments.

Particle accelerators detect subatomic particles using millions of sensors

Calorimeters measure the energy of particles. Tracking devices can measure momentum and charge from the trajectory of particles, which is determined by recording tiny electrical signals. Time-of-flight detectors provide particle velocities directly and particle mass indirectly, giving physicists a suite of properties to compare with those of known matter.

Cathode-ray tube televisions are examples of electron accelerators

CRT TVs work by converting electricity into heat, which causes electrons to be emitted from the rear of the device in three beams responsible for the colors red, green, and blue. Electromagnets direct electrons to phosphor molecules on the screen, which emit light and illuminate the pixels.

How radioactive isotopes are created and used for medical diagnostics

In particle accelerators, protons can be accelerated into other atoms to create radioactive isotopes, which can be attached to specific molecules to create radiotracers that are taken up by specific cells. Radiotracers can emit particles that produce light once they collide with an electron, and this light can be captured by a PET scanner to diagnose specific ailments.

Collisions between cosmic rays and atmospheric particles dwarf particle accelerators

According to Einstein's model of gravity, confining immense energy into a sufficiently small region would warp space-time enough to create a black hole. If accelerators actually did create black holes, then trillions more would be produced daily in the atmosphere, where collisions are millions of times more energetic.

View summaries of the most common types of radioactive decay and their associated particles

The alpha particle has the strongest ability to ionize other atoms it strikes, but it also does not travel very far before colliding with something and being absorbed. Gamma particles—high-energy photons—do not interact with matter as easily and therefore possess the greatest penetrating power, though this also makes their ionizing potential the smallest.

It may be possible to create dark matter in particle accelerators

In high-energy collisions, exotic forms of matter can be produced by directly converting energy into mass according to *E = mc*². Even though a dark matter particle would not be directly observable, its creation would result in unaccounted-for mass, which can be compared to potential dark matter candidates for indirect detection.

Particle accelerators have been used to reveal detailed ant anatomy

Using a synchrotron facility at the Karlsruhe Institute of Technology in Germany, a pair of X-ray beams swept across about 2,200 ant specimens to create over 200 terabytes of projection images from multiple angles. The images were compiled into micrometer-resolution 3D reconstructions of 792 species, which are freely accessible on the Antscan platform.

How the Antimatter Factory works, and why antimatter transport is so difficult

At CERN, protons are accelerated to 99.93% the speed of light and collide with iridium to create antiprotons. These particles are then slowed and sent to various research experiments. Moving the antimatter to other locations for study requires trapping it in electromagnetic fields to prevent contact with normal matter, which would cause annihilation.

Particle interactions follow rules related to specific quantum properties

Like a business whose purchased inventory matches sold inventory, physicists identified specific patterns across decades of particle accelerator data, which became new conservation laws for elementary particles. These laws help identify which particle decays are expected or forbidden.

The hypothetical particle that travels faster than light

Astrophysicists inspired by science fiction developed the theory of the tachyon—a Greek word for "fast"—which is a field or particle hypothetically able to travel faster than light. Although no experiments have confirmed any part of it, it's a fun theory to consider.

A 36-year-old Russian physicist survived a particle accelerator beam to the head

Several safety mechanisms failed during Anatoli Bugorski's inspection of malfunctioning equipment at the U-70 synchrotron, the Soviet Union's largest particle accelerator. Despite receiving as much as 600 times the lethal dose of radiation to the brain, he has shown no intellectual damage and worked until the age of 77.

Leptons do not experience the strong nuclear force that binds quarks together

Particles like electrons can exist in isolation, enabling them to move more freely. Within circuits, this allows electrons to carry energy across wire surfaces quickly. Contrastingly, light created in the sun's core is delayed by a million years on its way to Earth due to collisions with free electrons.

Photons emitted via stimulated emission have identical characteristics

When confined to a pair of mirrors, a single photon passing a region of population-inverted atoms can produce a chain reaction of monochromatic light. This chain reaction amplifies the initial photon, from which lasers get their name: light amplification by stimulated emission of radiation.

The trajectory of particles in bubble chambers reveals their properties

The presence of magnetic fields produces spiraling paths in charged particles as they move across the field, with faster and more massive particles moving in wider turns. Gaps in the trails indicate the presence of short-lived particles that are undetectable until they decay.

Lasers, semiconductors, medical imaging, and atomic clocks rely on quantum mechanics

Semiconductors, crucial in electronics, operate based on quantum superposition. Lasers use stimulated emission, a quantum process, and MRI machines leverage the quantum spin of hydrogen atoms for imaging. Atomic clocks measure time with unprecedented precision using quantum transitions.

Gamma Knife surgery uses incredibly precise, high-energy light to treat patients

A form of brain stereotactic radiosurgery, this non-invasive technology concentrates beams of light onto specific tumors to damage the DNA of malignant cells, killing them. The gamma rays used are in the same part of the electromagnetic spectrum as those produced in nuclear reactions, cosmic ray collisions, and radioactive decay.

The Louvre in Paris has its own particle accelerator for art analysis

The Accélérateur Grand Louvre d'analyse élémentaire serves as a noninvasive tool for identifying and quantifying trace elements present in artworks by analyzing how particles backscatter off targets. This information can help detect forgeries and determine a piece's provenance. (Some readers may experience a paywall.)

Random lasers can be created from biomaterials, such as peanuts and birch leaves

Rather than creating a narrow beam of light via amplification in an optical cavity, the random laser produces a red glow by scattering photons created in the natural pores of a peanut kernel after it has been injected with a solution of light-generating carbon dots derived from birch leaves.

Play an incremental game that teaches the history of particle physics

Developed during the CERN Summer Student Webfest 2014, this game tasks you with building the reputation of your particle accelerator as you discover particles and hire staff to collect data. A historical breakdown accompanies each discovery, allowing you to recreate the timeline of the field.

Watch the motion of an individual photon using a high-speed camera

Although light travels over 3 million football fields per second, cameras that capture trillions of frames per second can observe individual particles of light as they interact with atoms in materials they travel through. Such observations can be used to determine the speed of light in different materials.

Explore the National Cancer Institute's archive on treatments

Cancer is a complex disease with many different types, each with its own pathology. The best treatment may depend on characteristics specific to each person—even if two people share the same type of cancer. No single overview of treatments exists, but this resource from the National Cancer Institute lets you explore different options, side effects, an A-to-Z library of cancer drugs, and much more.

Learn about ionizing radiation and see the most radioactive places on Earth

The average person is exposed to radiation every day, though most of it is either harmless non-ionizing radiation or ionizing radiation at doses too small to significantly affect an individual. The highest doses of ionizing radiation are received by smokers due to the radioactive polonium and radioactive lead in tobacco products.

In 1971, a $35 ferret helped clean the Fermi National Accelerator Laboratory

Lacking cleaning robots, Fermilab scientists purchased a ferret named Felicia when metal slivers obstructing accelerated particles were identified. They trained her to run strings through vacuum tubes more than 90 meters long, and cleanser-dipped swabs were then tied to the strings and pulled through to remove the debris.

Listen to the sounds of pulsars, which emit radio pulses up to hundreds of times a second

Just as figure skaters spin faster by tucking in their arms, these celestial objects acquire high rates of spin from the collapse of the cores of massive stars. The star's rotation spins its magnetic field, generating beams of radio waves from its magnetic poles. If either of these poles faces a detector, the signals can be picked up and converted to audio signals.

How is immunotherapy used to fight cancer?

The Dana-Farber Cancer Institute provides a delightful Science Illustrated animation explaining PD-1/PD-L1 immunotherapy and how it fights cancer. Briefly, the treatment helps T-cells recognize cancerous cells that would ordinarily be "disguised" by proteins and attack. The fight is made more fair and effective by immunotherapy and similar cancer treatments.

Chemotherapy slows cancer by interfering with cell division

Cancer cells divide much more frequently than most normal cells. Most chemotherapy drugs are designed to interfere with cell division, thereby targeting harmful cells while attempting to leave healthy cells alone.

How to make your own DIY ionic thruster

In the search for more efficient, sustainable types of propulsive thrust, scientists have dabbled in developing engines using ionic thrust, a type of propulsion using the attractive force of oppositely charged ions. First introduced by a Russian...

A nuclear reactor's characteristic blue light is produced from superluminal particles

When light travels through water, its effective speed is 25% lower than its speed in a vacuum. Just as sound waves bunch up and produce a sonic boom when objects move faster than the speed of sound, particles moving faster than this reduced speed generate a shock wave of light, visible as a blue hue.

Take a 360-degree tour of ATLAS, one of two general-purpose detectors at the Large Hadron Collider and the largest particle detector by volume ever built. (VR device-compatible)

The speed of electricity may refer to the movement of electrons or energy

In the 18th century, various experiments, including one in which monks holding an iron wire were shocked, suggested that electricity traveled at infinite speed. Advancements in technology, recognizing that electric currents were moving electrons, and the development of the theory of electromagnetism showed that electric signals can travel at near light speed, despite electrons moving much slower.

Antimatter is the oppositely charged version of normal matter

When a particle and its antiparticle collide, they annihilate each other, creating a burst of energy. This makes creating large amounts of antimatter challenging because it must be isolated from any surrounding normal matter or be destroyed.

Lichtenberg figures capture lightning-like patterns within insulators

When high-energy electrons from particle accelerators are fired into materials like acrylic, they form a charged plane before discharging into scarred patterns within the material. By evenly charging a cylindrical bottle through rotation during the irradiation process, a 3D figure of lightning in a bottle can be created.

Nuclear-powered missiles replace chemical combustion with energy from nuclear fission

In these systems, energy is added to an airstream, which passes through a nozzle to generate thrust. Because the amount of energy released per unit mass of nuclear fuel is millions of times larger than that of chemical propellants, nuclear missiles can travel faster and farther with less fuel.

Solar sails use light as a means of propulsion

Photons possess momentum and can transfer it to objects they strike or bounce off, imparting radiative pressure, or a light-based force over a small surface area. Lasers fired at observational equipment with specially designed sails can theoretically use this mechanism to accelerate up to 20% the speed of light.

View the most expensive materials on Earth, led by those forged in particle accelerators

Californium-252—valued at $27.8M per gram, as of 2025—is far rarer and more valuable than gold, silver, or diamonds due to production and transportation costs. The most expensive substance ever found or created is antimatter, costing approximately $62.5T per gram.

An overview of radioactivity, which can spontaneously change one element into another

Unstable atomic nuclei can transmute into a new element—an atom with a different number of protons—by emitting an alpha particle (two protons and two neutrons) or a beta particle (an electron). The electron can emerge from the nucleus when a neutron, which has no charge, suddenly transforms into a proton and an electron, thereby maintaining zero charge before and after the transformation, but altering the original element.

A guide to building your own cloud chamber to observe cosmic rays

Using felt, alcohol, dry ice, and a clear container—such as a fish tank—you can create a region of supersaturated air that will cling to passing particles, forming trails of cloud-like droplets. Muons will create straight paths, alpha particles will leave thicker ones, and electrons or positrons will zigzag.

NASA uses a specialized plasma wind tunnel to test heat shield technology

The ArcJet Complex ionizes compressed air that fires onto shields at hypersonic speeds, replicating the conditions of high-speed, planetary reentry. An enhanced facility incorporates lasers to mimic the radiant heating experienced during high-energy atmospheric traversal.