The major objective of scientists is to find out exactly what parts make up the atom’s nucleus and the universe.

To know about these they bombarding the nucleus with projectiles called a particle.

The cyclotron one of the machines used to accelerate the positive or negative charged particles/ion’s to do the bombarding on the selected target is called a particle accelerator.

what is a cyclotron

It is a particle accelerator that is used to smash the nucleus of atoms and break them into more tiny parts or particles.

To achieve such a smashing power cyclotron accelerates particle almost at the speed of light.

When particles strike together with nucleolus such an extremely powerful momentum breaks into tiny and more tiny particles.

As increase acceleration, the momentum also increases thus more fundamental particle discovered.

The Large Hadron Collider ( LHC ) is the most common example used to discover Higgs Boson particle.

As a matter of fact, might say that some answers to research know about through these tests. At least partially scientists can see, may make predictions and a seasoned then test them out nicely.

Many of the facts about atoms have been learned through experiments designed to test predictions and hypotheses.

For example, experiments based on earlier hypotheses indicate that the central part of the atom is made up of protons and neutrons.

It is this nuclear which may be shattered in the process of atom-smashing using the atom smashers or the particle accelerators as call them cyclotron.

Medical cyclotron

Used in the production of medical isotopes accelerates protons at the speed of 6.5 MeV to 13 MeV.

Cyclotron sciences build upon the pioneering research in nuclear medicine and the existing suite of imaging tools.

The cyclotron produces radioisotopes for medical and biological research and for use in PET-CT scanners as tracers ( isotopes ).

The tracer is radioactive substances created by converting a stable element into an unstable or radioactive element they can be safely used to detect and diagnose the disease at the cellular level.

A negatively charged hydrogen ion is injected into the vacuum chamber of the cyclotron where 2-D shaped plates are enclosed between the poles of a powerful electromagnet.

And alternating positive and negative voltage between the D’s attracts and repels the ion in a circular path from one D to the other.

The ion gets a boost in energy every time it crosses the gap between the dis causing it to accelerate the magnetic field that holds the eye on within a horizontal plane.

Causing the ion to spiral toward the outside of the cyclotron as it accelerates.

When the ion hits the extraction foil or net it is stripped of its electrons leaving a positively charged proton that then travels down a beamline toward a target.

When the high energy proton collides with the nucleus of an atom in the target a nuclear reaction changes the atom structure creating a radioisotope.

The radioisotope is then added to a molecule in this case a sugar molecule ( FDG ) making a radiopharmaceutical that can easily be absorbed by the human body.

The target material containing the radioisotope is transferred from the end station via shielded lines and a series of pass-through access points.

To a hot cell in the production area. Once in the host cell, the operator uses the manipulating arms to extract the radioisotope from the target.

Time is of the essence as the radioisotope has already started to decay. While the radioisotope decays it releases the energy it is this energy that is detected by the Pet scan.

Radiopharmaceuticals produced at the cyclotron facility like all pharmaceutical production must follow strict and rigorous protocols.

It here to the quality assurance process of good manufacturing practices and health.

These protocols ensure that this center has qualified and trained personnel adequate premises and facilities and correct materials and labels.

Quality hearing to approve procedures to ensure the production of safe high-quality radiopharmaceuticals.

The radiopharmaceutical is packaged and placed into a shielded container to be transported to a hospital or used in the laboratory.

Upon arrival at the hospital, the radiopharmaceutical is prepared to be intravenously injected into the patient.

As it travels throughout the patient’s body the radioisotope decays it releases energy that is detected by the PET-CT scanner and used to generate 3-dimensional images.

The images reveal locations in the body where cells are taking up the most radioisotope the more active the cells the more radioisotope they absorb.

Being able to watch cell function provides medical professionals and researchers with critical information needed to diagnose disease plan new treatments or assess existing patient treatment.

nuclear-medicine-production-cyclotron-fdg

This catches one center for cyclotron sciences advances research in the expanding fields of molecular imaging, nuclear medicine, and other areas of science that make use of radioisotopes.

In particular, it will play a significant role in the research and treatment of diseases such as Cancer Alzheimer’s, and Heart disease.

And we’ll be a powerful imaging tool for innovative research into plant animal and human health.

Principal and working

The device developed by E. O. Lawrence and M. S. Livingston in 1934. It is used to accelerate charged particles like protons and neutrons. 

cyclotron-particle-source
Ion source : Technische Universität München

This results in the production of high energy charged particles. In nuclear physics, such energized particles are used to bombard nuclei causing nuclear reactions. 

A positively charged particle (Ions) accelerated to high energy with the help of an oscillating electric field and diagonal strong magnetic field. 

Two hollow half-cylinders made of highly conductive metals call as D’s are so placed that the straight edge will be face to face with a small gap between them. 

Now, these 2 D’s are connected to terminals of a high alternating voltage source. The voltage source helps to change the polarity of both D’s with selective frequency.

When the one D is at the positive potential then another one will be an exact opposite that is negative potential at the same time.

In this way, they would be oscillating and a variable electric field would be created between them. One electromagnet is kept below the D’s and another electromagnet is kept above the D’s. 

The bottom electromagnet has a north pole in the up direction and the top electromagnet will have a south pole below. 

This arrangement creates a magnetic field perpendicular to the direction of the electric field. This entire arrangement is seen in a vacuum box. 

The 2 D’s creates an electric field in the horizontal direction and electromagnets create a magnetic field in the vertical direction. 

what-is-a-cyclotron

When we place a positively charged particle which may be a proton or a combination of proton and neutron both. 

Since the one D is positive and the second D is negative there is an electric field between them. 

Now a force acts upon the charged particles and the direction would be as shown below.

F=qE  

Where, F = is the force experienced by a charge q when it is kept in the electric field E.

Because of this force, the charged particle gets accelerated and because of acceleration, the speed increases till it does enter another D.

a=qE/m

Where a = is the acceleration experienced by a charge q with mass m when it is kept in the electric field E.

Since D is an enclosed container so the value of the electric field inside D is zero. 

So the electric field force ( E ) becomes zero and also acceleration (a) becomes zero. 

Therefore inside of the container, there is no electric field (E) but the magnetic field present. But the magnetic field direction (B) is perpendicular to the charged particle is present.

Now the charged particle moves in the horizontal axes diagonal to the direction of the magnetic field.

It experiences a force in a direction perpendicular to the plane containing v and D. This force provides the centripetal force and makes the charged particles move along a circular path.

The radius ( R ) of circular path is represent by the equation.

R=mv/qB

Where, R = is the radius of charge q moving with velocity v and mass m when it is kept in the electric field E.

The particle makes a semi-circle and comes between the gap the time taken this t/2 where t is the time taken to complete one circle.

When the particle introduces at the center of the cyclotron its velocity remains zero. Due to electric field starts to accelerate and velocity increase.

When it enters the D with the velocity v remain constant inside the D because the alternating electric field becomes zero inside the D.

And diagonal magnetic field can not change the velocity of the particle. But as soon as charge/particle reaches the end of D and electric field polarity changes.

Then again particle experience force and thus get accelerated in result velocity increases till it enters another D.

In such a way in every next rotation, the kinetic energy of the particle increases thus the radius of rotation also increases.

At the end reaches the boundary from where passes through the window and hits the target. The scientists who involved in particle research use cloud chambers.

This is a small object whatever the size all cloud chamber is consists of a drum-like compartment sealed over with glass inside there is gas saturated with water vapor.

Any charged particles passing through this chamber leaves a trail of water vapor similar to the cloud trail left by a high flying airplane on a cold day.

The trail in the cloud chamber can be eliminated and photograph. By calculating the mass and velocity using a trail predicts new particles.

Synchrocyclotron

The synchrocyclotron used when the velocity of the Deuteron nucleolus or alpha-particle needs to control by applying variable frequency alternating voltage.

Varied to compensate for relativistic effects as the particles’ velocity begins to approach the speed of light.

Here use only one D instead of 2-D as in the classical cyclotron. For targeting the electrostatic deflector is used.

Isochronous cyclotron

The isochronous is an alternative to the synchrocyclotron.

which has a varying magnetic field that increases with radius, rather than with respect the time. Isochronous are capable of producing much greater beam current than synchrocyclotrons.

But require azimuthal variations in the field strength to provide a strong focusing effect and keep the particles captured in their spiral trajectory.

Types and uses

do have marvelous research tools in these atoms smashers. Principally they are three different kinds.

1 Cyclotrons

2 Betatron

3 Linear Accelerator or LINAC

Each of these 3 particle accelerators operates on a different principle. Accelerate heavy positive particles like protons from hydrogen.

The Betatron accelerates electrons which are negative particles. Linear accelerators are used to accelerate either positive or negative particles.

The common application of linear accelerator in medical purposes as radiation therapy in cancer treatments.

medical-cyclotron
source : GE

Are X-Ray machines are kind of particle accelerator sort of an atom smasher?

Yes, the X-Ray tube is an accelerator, So is the picture tube in your television set.

But X-Ray tubes can provide energies to electrons of only about the 200k Volts.

To know more about medical devices like MRI ( magnetic resonance imaging ), CT Scan, Ultrasound, or Sonography click on the links.

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