Page 80 - A Life - my Live - my path

My career - the IRE

the cyclotron to work properly. The electrical power
supplies, vacuum pumps, and physical and nuclear
protection systems were all closely monitored. The building
was large enough to contain office space, a meeting room,
the mechanical and electronics laboratories, a room for the
vacuum pumps, a room for the water pumps, a room for the
power supplies, a control room, and finally the casemate in
which the machine was housed.

A cyclotron is made up of a closed casing
with, inside, two metal cavities in the

shape of a half-cylinder (called "dee")
separated by a gap. A very high vacuum (10 ) is created in
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the closed chamber. To operate, the “dee” are supplied with

alternating electrical voltage and subjected to a uniform
magnetic field created by very powerful electromagnets.
A source is used to inject protons into the centre of the
cyclotron, which are deflected by the uniform magnetic field
(the magnetic field does not accelerate the protons). At each
half-turn, depending on the frequency of the electric field,
the protons are accelerated and deflected again by the
magnetic field. The protons are therefore accelerated twice
per revolution and the trajectory forms a spiral. After a large
number of revolutions, the protons, which have reached
relativity speeds (i.e. a high energy e=mc²), are deflected to leave
the interior of the cyclotron by a very distinctive part called

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