Define Synchrotron
The term synchrotron comes from physics. A synchrotron is a cyclotron where the strength of the magnetic field increases with the particles' energy to keep their orbital radius constant. A synchrotron is a machine about the size of a football field, which accelerates electrons to almost the speed of light. While the electrons are deflected through magnetic fields, they emit incredibly bright light. The light is channeled down beamlines to experimental workstations where it is used for research work. Synchrotrons can accelerate beams of protons to an energy of 6.5 teraelectronvolts(or TeV). The principle was invented by Vladimir Veksler in 1944.
How Does Synchrotron Work?
A synchrotron is a fundamental principle of physics, that when charged particles are accelerated, they give off electromagnetic radiation. It is a potent source of X-rays. As the X-rays circulate the synchrotron, they are produced by high energy electrons. An everyday example of this effect is the radio-transmitter in which the electrons in the transmitter mast; here, the accelerations are such that the radiation produced is in the ratio-frequency range. The most common synchronous also uses electrons through their speed and acceleration is such that they produce electromagnetic radiation that is not only in the radio-frequency range but also present in the infra-red, ultra-violet, visible and X-ray portion of the electromagnetic spectrum.
Particles are generated in an electron gun, mostly like the cathode ray tubes found in old TV sets. They are then stimulated up to very high speeds through a series of three particle accelerators. These are called the linac, or linear accelerator, the booster synchrotron, and the large storage ring.
The storage ring is not a right circle, but a polygon made of straight sections angles together with bending magnets. These bending magnets or dipole magnets are used to steer the electrons around the ring. As the electron goes through each magnet, it loses energy in the form of light. This light can then be channeled out of the storage ring wall and into the experimental stations called beamlines.
Third generation synchrotrons such as diamonds also use individual arrays of magnets called insertion devices placed in the straight sections of the ring. These cause the electrons to follow intense and tuneable light.
Electron Synchrotron
Electron synchrotron is a type of synchrotron designed to accelerate electrons to high energies. The electron synchrotron was invented in 1945 in the USA. It is a particular application of their general principle of phase stability. High energy physics at Bonn started in 1953 when it was decided to build a 500 MeV electron synchrotron. The largest electron synchrotrons which are used in particle physics research, operate as colliding-beam storage rings. At CERN, the Large Electron-Positron collider was initially designed to accelerate electrons and positrons to 50 GeV and later to about 100 GeV in a ring with a 27 km circumference. Another way of reducing the energy used in an electron synchrotron is to employ superconducting radio-frequency accelerating cavities.
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Difference Between Cyclotron And Synchrotron
The differences between cyclotron and synchrotron are: A cyclotron accelerates the particles in a spiral since the magnetic field is constant. The synchrotron adjusts the magnetic field such that the particles are kept in a circular orbit. A cyclotron is a cylindrical or spherical chamber, whereas synchrotron is a torus-shaped tube. Cyclotron produces continuous and unpulsed beams while synchrotrons produce discontinuous beams. Cyclotrons have high accuracy magnetic fields, whereas synchrotrons have a natural correction of the beam because of ample space between electromagnets. Cyclotrons can fit in a tiny place while synchrotrons require ample space.
Solved Examples
Question: How much does a synchrotron cost?
Answer: Synchrotrons are essential for cutting-edge research. They are the large machines, costing tens or hundreds of millions of dollars to build, and each beamline costs another two or three million dollars on average.
Fun Facts
The vacuum created inside the synchrotron is at the level of 10-11 bar, meaning that in 1cm3, there are about 100 00 particles of gas. The linear accelerator in the synchrotron is 40 meters long and weighs about w3 tons. One of the magnets from the vacuum chamber weighs about 8 tons. This is important in medical imaging. The circumference of the synchrotron's ring is 96 m.
FAQs on Synchrotron
1. What is a synchrotron and what is its fundamental working principle?
A synchrotron is a large, ring-shaped particle accelerator. Its fundamental principle is based on accelerating charged particles, like electrons or protons, to nearly the speed of light. As these high-energy particles are forced to travel in a circular path by powerful magnets, they emit extremely bright and focused electromagnetic radiation, known as synchrotron light. The key feature is that both the magnetic field and the accelerating electric field's frequency are precisely synchronised with the particle's increasing energy to maintain a fixed orbital radius.
2. What are the main components of a typical synchrotron?
A synchrotron is a complex machine composed of several key parts that work in sequence:
- Electron Gun: Generates the initial beam of electrons.
- Linear Accelerator (Linac): Provides the first stage of acceleration for the particles.
- Booster Ring: A smaller accelerator that increases the particles' energy before they enter the main ring.
- Storage Ring: The main, large ring where particles circulate at high energy, guided by magnets. This is where synchrotron light is produced.
- Beamlines: Channels that guide the synchrotron light from the storage ring to experimental workstations.
- End Stations: The experimental areas where researchers use the light for their studies.
3. How does a synchrotron differ from a cyclotron in its design and operation?
The primary differences between a synchrotron and a cyclotron lie in their magnetic fields and particle paths:
- Particle Path: In a cyclotron, particles follow an outward spiral path. In a synchrotron, they travel in a fixed circular path.
- Magnetic Field: A cyclotron uses a constant magnetic field. A synchrotron uses a variable magnetic field that increases as the particles gain energy to keep them in the same orbit.
- Size and Shape: Cyclotrons are relatively compact cylindrical chambers, while synchrotrons are much larger, torus-shaped rings that can be several hundred metres or even kilometres in circumference.
4. What is synchrotron radiation and what makes it a unique tool for scientists?
Synchrotron radiation, or synchrotron light, is the electromagnetic energy emitted by charged particles when they are accelerated and deflected by magnetic fields in a synchrotron. This light is unique because it is:
- Extremely Bright: Millions of times brighter than the sun, allowing the study of very small or dilute samples.
- Highly Focused: It can be focused onto a tiny spot, providing high-resolution data.
- Broad Spectrum: It covers a wide range of wavelengths, from infrared to hard X-rays, making it versatile for many different experimental techniques.
- Pulsed: The light is produced in very short flashes, enabling scientists to observe chemical and biological processes in real-time.
5. Why is it necessary to increase the magnetic field strength in a synchrotron as particles accelerate?
In a synchrotron, the goal is to keep particles in a fixed-radius orbit. The centripetal force required to bend a charged particle's path in a magnetic field depends on its momentum. As particles are accelerated by electric fields, their momentum increases significantly. To counteract this and prevent the particles from spiralling outwards, the magnetic field strength (B-field) must be increased in sync with the particle's rising energy. This synchronisation ensures the bending force is always just right to maintain the fixed circular path, which is the defining characteristic of a synchrotron.
6. In what fields are synchrotrons used, and can you provide some real-world examples?
Synchrotrons are versatile tools used across numerous scientific and industrial fields. Their powerful light helps researchers study the structure of matter at the atomic level. Key application areas include:
- Medicine and Biology: Determining the structure of proteins and viruses to develop new drugs (e.g., for HIV and COVID-19) and for advanced medical imaging.
- Materials Science: Developing new materials, such as stronger alloys, more efficient solar cells, and better batteries.
- Environmental Science: Analysing pollutants in soil and water.
- Archaeology and Art: Examining ancient artefacts and artworks without damaging them.
- Consumer Products: Improving everyday items, from the texture of chocolate to the effectiveness of cosmetics.
7. Is the Large Hadron Collider (LHC) at CERN considered a synchrotron?
Yes, the Large Hadron Collider (LHC) is a powerful example of a synchrotron. In fact, it is the world's largest and most powerful particle accelerator. It uses a 27-kilometre ring of superconducting magnets to steer and accelerate two beams of protons in opposite directions to extremely high energies. Like all synchrotrons, the LHC's magnetic fields are ramped up as the particles' energy increases to keep them on a precise, fixed circular path before they are made to collide.
8. Does India have its own synchrotron research facilities?
Yes, India has indigenous synchrotron radiation sources located at the Raja Ramanna Centre for Advanced Technology (RRCAT) in Indore. The facility operates two synchrotrons, named Indus-1 and Indus-2. These machines serve as national research facilities, providing powerful X-ray and UV radiation beams to scientists and researchers from various institutions across the country for advanced studies in physics, chemistry, biology, and materials science.
