4/2003 Rev 2 I.4.10 – slide 1 of 25 Session I.4.10 Part I Review of Fundamentals Module 4Sources of Radiation Session 10Linear Accelerators, Cyclotrons and Betatrons IAEA Post Graduate Educational Course Radiation Protection and Safety of Radiation Sources

4/2003 Rev 2 I.4.10 – slide 2 of 25  In this session we will discuss Charged Particles  We will discuss the acceleration of Charged Particles by:  Linear Accelerators  Cyclotrons  Betatrons Overview

4/2003 Rev 2 I.4.10 – slide 3 of 25 Charged Particles  Useful for High Energy Research  Used directly in medical modalities (electron beam therapy)  Used to produce radionuclides employed in medical practices such as positron emitters for Positron Emission Tomography (PET)

4/2003 Rev 2 I.4.10 – slide 4 of 25 Charged Particles  A charged particle is any atomic particle with a positive or negative charge  A positive charge means the particle is a proton or positron or is an atom or molecule missing one or more electrons  A negative charge means the particle is an electron or beta particle

4/2003 Rev 2 I.4.10 – slide 5 of 25 Charged Particles  Charged particles are attracted to objects possessing an opposite charge (positive to negative and negative to positive)  Charged particles are repelled by objects with similar charge (positive vs positive and negative vs negative)  Attraction and repulsion are used to accelerate charged particles +- ++

4/2003 Rev 2 I.4.10 – slide 6 of 25 Basic Charged Particle Accelerators This is an X-ray tube – it accelerates negatively charged electrons across a linear path, however, it is not considered a linear accelerator

4/2003 Rev 2 I.4.10 – slide 7 of 25 Other Charged Particle Accelerators Van der Graff Generator

4/2003 Rev 2 I.4.10 – slide 8 of 25 Linear Accelerators Once the particle has drifted through the first cavity, the polarity switches as seen in (b). The particle now is repelled by the first cavity and attracted by the second. After it drifts through the second cavity, the polarity again reverses so that the particle is repelled as it exits the second cavity (c). All three images represent the same two cavities. The positively charged particle is attracted to the negatively charged first cavity in (a).

4/2003 Rev 2 I.4.10 – slide 9 of 25 Linear Accelerators The drift tubes get longer as the particle’s velocity increases so that it spends the same amount of time in each tube.

4/2003 Rev 2 I.4.10 – slide 10 of 25 Electron Accelerators Waveguides

4/2003 Rev 2 I.4.10 – slide 11 of 25 Linear Accelerators

4/2003 Rev 2 I.4.10 – slide 12 of 25 Electron Accelerators 6 MV short waveguide

4/2003 Rev 2 I.4.10 – slide 13 of 25 Electron Accelerators 18 MV long waveguide

4/2003 Rev 2 I.4.10 – slide 14 of 25 Electron Accelerators Bending the electron beam

4/2003 Rev 2 I.4.10 – slide 15 of 25 Electron Accelerators

4/2003 Rev 2 I.4.10 – slide 16 of 25 Linear Accelerators

4/2003 Rev 2 I.4.10 – slide 17 of 25 Cyclotron

4/2003 Rev 2 I.4.10 – slide 18 of 25 Cyclotron

4/2003 Rev 2 I.4.10 – slide 19 of Cyclotron

4/2003 Rev 2 I.4.10 – slide 20 of Cyclotron

4/2003 Rev 2 I.4.10 – slide 21 of 25 Cyclotron

4/2003 Rev 2 I.4.10 – slide 22 of 25 Cyclotron

4/2003 Rev 2 I.4.10 – slide 23 of 25 Betatron

4/2003 Rev 2 I.4.10 – slide 24 of 25 Betatron target x-ray beam electron gun donut orbit

4/2003 Rev 2 I.4.10 – slide 25 of 25 Where to Get More Information  Cember, H., Johnson, T. E., Introduction to Health Physics, 4th Edition, McGraw-Hill, New York (2008)  Martin, A., Harbison, S. A., Beach, K., Cole, P., An Introduction to Radiation Protection, 6 th Edition, Hodder Arnold, London (2012)  Firestone, R.B., Baglin, C.M., Frank-Chu, S.Y., Eds., Table of Isotopes (8 th Edition, 1999 update), Wiley, New York (1999)