EG0800258 Developments and Applications of Particle Accelerators

M.M. Abdelrahman and A.G.Helal Accelerators & Ion Sources Department, Nuclear Research Center, Atomic Energy Authority P.O. Box: 13759Inchas, Atomic Energy, Cairo, Egypt. ([email protected])

ABSTRACT Particle accelerators are now widely used in many fields of applications as scientific researches, applied , medicine, industrial processing and agriculture, biology, chemistry etc. The physics and technology of accelerators involve many branches of science. These include electromagnetism, solid state properties of matter, , plasma physics and quantum physics. In this article, a history of particle accelerators will be discussed. Also, the important milestones in the accelerators development up to the present day are given. Finally, a various applications of accelerators have also discussed.

INTRODUCTION Particle accelerators are generators that produce beams of charged particles acquiring energies from few KeV up to thousands of millions of eV dependent on the type of the accelerator. The design of the accelerator must include consideration of voltage breakdown, the optical characteristics, mechanical convenience and pumping speed. Particle accelerators could be divided according to the following classifications (1):

(1) The type of the charged particles to be accelerated such as; protons, deuterons, electrons, ions etc. (2) The energy of the accelerator such as low, high or super high energy accelerators, usually the direct current types with few hundred kilovolts are low energy accelerators. (3) Some types of accelerators are named according to the direction of acceleration such as linear or cyclic accelerators.

Particle accelerators are devices producing beams of energetic particles such as ions and electrons which are employed for many different purposes (2) as, creation of new particles, high brightness photon sources for material analysis and modification, ion implanters for surface modifications and for sterilization and polymerization and for radiation surgery and therapy of cancer. Particle accelerators are one of the most versatile instruments designed by physicists. From their start, as the cathode ray tube by J.J. Thomson who applied it to discover the electron, to the present giant colliders which were accompanied with the major milestones of nuclear and (3).The evolution of accelerators development can be summarized by the Livingston chart (4) as shown in Fig. 1, where the equivalent energy is plotted as a function of time.

10000Tev

1000Tev

100Tev

10Tev Proton Synchrotrons Electron Linacs Accelerator beam energy 1Tev

100Gev Electron Synchrocyclotrons Synchrotrons Proton Linacs 10Gev Betatrons

Cyclotrons 1Gev

100Mev

10Mev

1Mev

1930 1940 1950 1960 1970 1980 1990 2000 2010

Year

Fig. 1: The developments of particle accelerators according to the Modified Livingston.

APPLICATIONS OF ACCELERATORS

Today particle accelerators are widely used in nearly every field of physics from elementary particles to solid state physics. They are also considered to be an essential part in many other areas of research as chemistry, biology, etc (5). Industrial applications cover a wide range as ion implantation in the semiconductor industry, and the modification of surface properties of many materials. Applications of accelerators in medicine have found wide areas as isotope production in the view of diagnostics or treatment, or for therapy with gamma rays and more recently, with neutrons and heavy charged particles.

Heavy particle therapy Isotope dating Fusion studies SYNCHROTRON Nuclear reaction MEDICAL APPLICATION Backscattering Micromechanics MATEIAL Microstructures lithography Ceramics ANALYSIS SYNCHROTRON Glasses Metals RADIATION Proteomics 1970 Radioisotope production CYCLOTRO Semiconductors ION 1965 MEDICAL APPLICATION IMPLANTATION Radiation Therapy BETATRON Polymermodiffication by e- beams ELECTROSTATIC 1940 LINAC ELECTRON ACCELERATORS

1930

NUCLEAR PHYSICS

Fig. 2: The importance of particle accelerators (5).

1- Atomic physics The area of the activity of particle accelerators in atomic physics is increased by time due to technological advances of the accelerator structures that allowed the diversify of the ion species and to increase the ion beam energy and intensity. A large amount of research is conducted in many institutes in different applications such as: Electron emission following fast ion impact on thin solid targets (6), charge exchange cross sections (7, 8) and mechanisms of atomic collisions and ionization process (charge distribution and rotational properties of electron clouds during collisions) (9).

2- Plasma physics Applications of particle accelerators help in explaining and solving problems in the field of fusion research (10) and laboratory plasmas (11).

3- Particle physics Developments of particle physics have been determined by the progress that achieved in building accelerators of still increasing energy. Accelerator physics is a branch of applied science. There are many Labs are conducting with studying of particle physics using a developed accelerators as CERN (12), Stanford Linear Accelerators (13) and Brookhaven AGS machine (14), etc. Developments in technology give rise to new trends in particle physics research, since higher energy leads to new discoveries. As an example for recent applications of particle accelerators in particle physics is the International Linear Collider (ILC) (15) which is a proposed future international . It would create high-energy particle collisions between electrons and positrons, their antimatter counterparts. The ILC would provide a tool for scientists to address many of the most compelling questions of the 21st century-questions about dark matter, dark energy, extra dimensions and the fundamental nature of matter, energy, space and time.

4- In the past, nuclear physics research has been performed towards the study of the structure of individual nuclei, their excited states and the associated spectroscopy. The availability of heavy ion-machines allows the dynamics of nucleus-nucleus collisions and the fragmentation of nuclei to be studied.

5- Biology and chemistry Accelerators are a source of radiation, where study of radiation biology using accelerators have been mainly concentrated at understanding the molecular thorough of radiation damage (16). Electron accelerators with energies up to a few MeV are used in radiation chemistry studies (17). Nowadays, using a synchrotron radiation which produced from electron accelerators with high energies to study the dynamics of biological processes became possible (15).

6- Medicine Accelerators are used in medicine for diagnostics and for therapy. Radioisotopes have proved that they can give a powerful biochemical and physiological information when injected into living organisms (18).

7- Analysis of elements The various accelerator laboratory techniques for sample structure analysis and trace element detection are now widely used in applied science, geology; mineralogy and etc…Particle beams with a certain energy produced by a particle accelerator are suited for material analysis because of their interaction with matter. There are many various methods are extremely helpful in material analysis and modification (Fig. 3) (19), (20).

MeV-Ions Back scattering

RBS

Sample

X-rays Recoil γ-radiation PIGE PIXE ERD

Fig. 3: Processes relevant to ion-beam analysis (19, 20). 8- Industrial processing Industrial applications cover a wide range as ion implantation (21, 22). Ion implantation for manufacturing semiconductors is one of the major present industrial applications of particle accelerators (18). Ion implantation can also be used to modify other properties as surface hardness, corrosion resistance, friction coefficient, etc. Radiation process to preserve food, sterilize toxic waste (23). Activation methods with very small accelerators produced neutrons are applied in and are still being developed for the detection of explosives.

REFERENCES (1) M.E. Abdelaziz; Particle Accelerators; Nuclear technology in developing countries, 3 Arab development institute (1980) (2) D. Robin, Historical overview, examples and applications, USPAS School, Arizona State University, Phoenix, USA, January 16-27 (2006). (3) A.R. Steere, M.Sc. Thesis, Department of Physics and Astronomy, Michigan State University, USA (2005) (4) H.F. Dylla, CERN Accelerator School, Platja D Aro, Spain, May 16-24 (2006) (5) U. Amaldi, Euro physics News, 31, (2000) (6) F. Aumayr et al, Phys. Rev. Lett., 71 (1993) 1943 (7) M. Albu, F. Aumayr and HP. Winter, Int. J. Mass. Spectrom. 233 (2004) 239 (8) A. Kumar and N.F. Lane, Phys. Rev. A 43 (1991) 217 (9) H.S.W. Massey and H.B. Gilbody, Electronic and Ionic Impact Phenomena, Vol. 4, Oxford, Clarendon press (1974) (10) J. Wesson, The Science of JET, JET, Oxfordshire, England (1999) (11) J-M Noterdaeme, 12th International Conference on Emerging Nuclear Energy Systems (ICENES), Bruxelles, Belgium, August 21-24 (2005). (12) http://public.web.cern.ch/Public/Welcome.html (13) http:// home.slac.stanford.edu/ppap.html (14) http:// www.bnl.gov/cad/

(15) http// www.-bd.fnal.gov –Run II Handbook

(16) M. Folkard et al, Journal of physics: Conference Series 58 (2007) 62 (18) O. Barbalat, CERN Accelerator School, KFA, JULICH, Fed. Rep. Germany, September 17-28 (1990). (19) V. Ignatova et al, Progress in Surface Science 81 (2006) 247 (20) A. Denker et al, CERN Accelerator School, Zeegse, 24 May- 2 June (2005) (21) Jorg K.N. Lindner, CERN Accelerator School, Zeegse, Netherlands, 24May to 2 June (2005) (22) J. Narojczyk et al, Vacuum, 78 (2005) 229 (23) M.R. Cleand, CERN Accelerator School, Zeegse, Netherlands, 24May to 2 June (2005)