Investigory project for class 12 board exam on the topic CYCLOTRON.

2. ACKNOWLEDGEMENT
I undertook this Project work , as the part of my XII-Physics project .I had tried to
apply my best of knowledge and experience gained during study and class
work experience.
I would like to extend my sincere thanks and gratitude to my teachers Mrs.
MAHAK AHUJA and Mr. S.V. YADAV
I am very much thankful to our principal Dr. RAJESH SHARMA for giving
valuable time and moral support to develop this project.
I would like to take the opportunity to extend my sincere thanks and gratitude to
our parents for being a source of inspiration and providing time and freedom to
develop this project.

3. CERTIFICATE
This is to certify that the project / Dissertation entitled CYCLOTRON is a bonafide work done by Master EKANSH WAGADARE of
class XII Session 2016-17 in partial fulfillment of CBSE’s AISSCE Examination 2016-17 and has been carried out under my
direct supervision and guidance . This report or a similar report on the topic has not been submitted for any other examination
and does not form a part of any other course undergone by the candidate.
EXTERNAL PRINCIPAL INTERNAL

4. • Cyclotrons accelerate charged particles using a high-frequency, alternating
voltage (potential difference).
• The cyclotron was invented by Leo Szilárd and first manufactured by Ernest
Lawrence .

5. • A cyclotron is used for accelerating positive ions, so that they acquire energy
large enough to carry out nuclear reactions.
• Cyclotron was designed by Lawrence and living stone in order to overcome the
drawbacks of the linear accelerator at the drawbacks of the linear accelerator
at the University of California, Berkley, in the early 1930’s and is used to
accelerate charged particles like protons and deuterons.
• This results in the production of high energy beam which is then used for
artificial disintegration, etc.
• These type of particle accelerator were among the first devised and have
several advantages over early linear accelerators, such as smaller size
requirements.
• Particle acceleration typically requires a fairly great distance to allow the
particles to come to sufficient speed for use in experiments.
• The design of a cyclotron, however, allows for smaller accelerators to be used
to great effect, since the particle moves in a circular motion and travels a great
distance without requiring a long straight corridor for passage.

6. PRINCIPLE
• A cyclotron accelerates a charged particle beam using a high
frequency alternating voltage which is applied between two hollow "D"-shaped
sheet metal electrodes called "dees" inside a vacuum chamber.
• The dees are placed face to face with a narrow gap between them, creating a
cylindrical space within them for the particles to move. The particles are injected
into the center of this space. The dees are located between the poles of a
large electromagnet which applies a static magnetic field ”B” perpendicular to
the electrode plane.
• The magnetic field causes the particles path to bend in a circle due to the Lorentz
force perpendicular to their direction of motion.
• If the particles' speed were constant, they would travel in a circular path within the
dees under the influence of the magnetic field. However a radio frequency (RF)
alternating voltage of several thousand volts is applied between the dees. The
frequency is set so that the particles make one circuit during a single cycle of the
voltage.

7. • Each time after the particles pass to the other dee electrode the polarity of the
RF voltage reverses. Therefore, each time the particles cross the gap from
one dee electrode to the other, the electric field is in the correct direction to
accelerate them.
• The particles' increasing speed due to these pushes causes them to move in
a larger radius circle with each rotation, so the particles move in a spiral path
outward from the center to the rim of the dees. When they reach the rim the
particles exit the dees through a small gap between them, and hit a target
located at the exit point at the rim of the chamber, or leave the cyclotron
through an evacuated beam tube to hit a remote target.
• Various materials may be used for the target, and the nuclear reactions due
to the collisions will create secondary particles which may be guided outside of
the cyclotron and into instruments for analysis.
• In the cyclotron, in contrast, the particles encounter the accelerating voltage
many times during their spiral path, and so are accelerated many times, so the
output energy can be many times the accelerating voltage.

9. CONSTRUCTION
• D1 and D2 are hollow evacuated metal chambers called dees . The dees are
connected to a high frequency oscillator. The two dees are enclosed in a
evacuated steel box.
• The box is placed in a strong magnetic field produced by two pole pieces of
electromagnet.

10. WORKING
• The positive ion to be accelerated is placed in between the dees. Let D1 is at
negative potential and D2 is at positive potential. The ion will be accelerated
towards D1
• On reaching inside D1 the ion will be in field free space(electric field is zero).Due
to perpendicular magnetic field it describes a semi circular path inside D1 of radius
r=mv/Bq.
• Time taken by the ion to cover semi circular path is t= πm/Bq. This time is
independent of speed of the ion and radius of its path.
• The time during which positive ion describe a semi circular path is equal to the
time of half cycle of electric oscillator and at the same instant polarity of the dees
are reversed.
• Now D1 becomes positive and D2 becomes negative.
• The ion is accelerated towards D2. It enters D2 by crossing electric field between
D1 and D2 therefore inside D2 it describes semi circular path of greater radius
(velocity increases due to electric field).

11. • As time period is independent of speed and radius therefore the ion will arrive in the
gap when the polarity of the dees is reversed. therefore, positive ion will go on
accelerating every time it comes in the gap between the dees.
• The accelerated ion can be removed out of the dees from window , by applying electric
field.

12. CYCLOTRON RADIATION
• Cyclotron radiation is electromagnetic radiation emitted by moving charge
d particles deflected by a magnetic field. The Lorentz force on the particles
acts perpendicular to both the magnetic field lines and the particles' motion
through them, creating an acceleration of charged particles.

13. CYCLOTRON
FREQUENCY

14. ADVANTAGES OF CYCLOTRON
• Cyclotron has a single electrical driver, which saves both money and power, since
more expense may be allocated to increasing efficiency.
• Cyclotrons produce a continuous stream of particles at the target, so the average
power is relatively high.
• The compactness of the device reduces other cost as its foundations, radiation
shielding, and the enclosing building.
• In the medical area we are developing the cyclotron as a proton treatment source.
More medical facilities are being set up with the cyclotron providing accelerated
protons to irradiate tissue. The proton, unlike gamma rays, has a depth of
penetration that can be finely tuned (by ”turning” the cyclotron) to limit damage to
other tissues.
• The cyclotron is also used to create radioactive materials that are used as
radiation sources which can be implanted. The radioactive materials can also be
used as tracers in medical work ups and in research, and also to provide
“luminosity” in some imaging because of the way tissue takes up these selected
materials.

15. USES OF CYCLOTRON
• For several decades, cyclotrons were the best source of high-energy beams
for nuclear physics experiments; several cyclotrons are still in use for this
type of research.
• Cyclotrons can be used to treat cancer. Ion beams from cyclotrons can be
used, as in proton therapy, to penetrate the body and kill tumors by radiation
damage, while minimizing damage to healthy tissue along their path.
• Cyclotron beams can be used to bombard other atoms to produce short-lived
positron-emitting isotopes suitable for PET imaging
• There are basically two applications for the cyclotron. It's a particle
accelerator, and, though it can be adapted to accelerate any charged particle,
it is most frequently applied to accelerate positive charges. Protons are
frequently the choice. We use the cyclotron in the physics lab, and in
medicine.

16. • In the medical area we are developing the cyclotron as a proton treatment source.
More medical facilities are being set up with the cyclotron providing accelerated
protons to irradiate tissue. The proton, unlike gamma rays, has a depth of
penetration that can be finely tuned (by "tuning" the cyclotron) to limit damage to
other tissues.
• The cyclotron is also used to create radioactive materials that are used as radiation
sources which can be implanted. The radioactive materials can also be used as
tracers in medical work ups and in research, and also to provide "luminosity" in
some imaging because of the way tissue takes up these selected materials. These
mostly short-lived radionuclide's are "big business" in medical and biophysics.
• In the physics laboratory, we use the cyclotron to create particle streams that we
then slam into targets. This is the continuation of research to investigate the
quantum mechanical world. The cyclotron can be used to "feed" another or other
accelerators to get higher energies and a "bigger bang" in the world of collisions.

17. THEY WORK ON THE PRINCIPLE OF
CYCLOTRON

18. WORLD’S LARGEST CYCLOTRON
• The world’s largest cyclotron built and commissioned in 1947 in 1974 at
Canada’s National Laboratory for particle and Nuclear Physics, known as the
TRIUMF Laboratory, in Vancouver, British Columbia, Canada, reached
energies of 500 MeV .Thirty six years later, it is still world’s largest and one of
the crowning achievements of modern engineering.
• Through subsequent modifications, the TRIUMF cyclotron is now producing
three times the beam intensity it was designed for.
• This was a unique accelerator, the only one in its energy range that
accelerated H-ions instead of protons.
• The huge cyclotron has a 4000-ton main magnet 18 meters (59feet) in
diameter and a main RF amplifier that delivers almost 1 million watts of
power.

19. • Because the TRIUMF cyclotron can provide very intense beams of protons, it’s
been able to perform some of most detailed science experiments in particle and
nuclear physics, enabling researchers to examine hundreds or millions of reactions
and look for deviations and extremely rare reactions.

20. CYCLOTRON IN INDIA
• Variable Energy cyclotron centre (VECC) is located in Calcutta, India. The
centre building itself houses a 224cm cyclotron, was the first of its kind in
India, having been operational since 1977-06-16 .It provides proton,
deuteron, alpha particle and heavy ion beams of various energies to other
institutes.

21. • www.wikipedia.com
• S.L. Arora
• Google Images