Summer Student Lectures. Oliver Brüning SL/AP. ttp://bruening.home.cern.ch/bruening/summer school/lecture1

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1 Accelerators Summer Student Lectures 2002 Oliver Brüning SL/AP ttp://bruening.home.cern.ch/bruening/summer school/lecture1

2 Particle Accelerators Physics of Accelerators: High power RF waves Cryogenics Super conductivity Magnet design construction Vacuum surface science, solid state physics, electro dynamics, engeneering, computer science Physics of Particle Beams: Single particle dynamics Collective effects Two beam effects classical and quantum mechanics, nonlinear dynamics, relativity, electro dynamics, computer science

3 Overview I ) Particle Acceleration II ) Storage Rings Trajectories III) IV) Orbit Stability Long Term Stability Synchrotron Radiation Collective Effects V) LEP,LHC more

4 Overview and History: S. Weinberg, The Discovery of Subatomic Particles, Scientific American Library, (ISBN or [pbk]) ( WEI) C. Pellegrini, The Development of Colliders, AIP Press, (ISBN ) (93: PEL) P. Waloschek, The Infancy of Particle Accelerators, DESY 94039, R. Carrigan and W.P. Trower, Particles and Forces At the Heart of the Matter, Readings from Scientific American, W.H. Freeman and Company, Leon Lederman, The God Particle, Delta books 1994 Lillian Hoddeson (editor), The rise of the standard model: particle physics in the 1960s and 1970s, Cambridge University Press, 1997 S. Weinberg, Reflections on Big Science, MIT Press, 1967 (5(04) WEI) Introduction to Particle Accelerator Physics: Mario Conte and William McKay, An Introduction to the Physics of Particle Accelerators, Word Scientific, 1991 H.Wiedemann, Particle Accelerator Physics, Springer Verlag, CERN Accelerator School, General Accelerator Physics Course, CERN Report 8519, CERN Accelerator School, Second General Accelerator Physics Course, CERN Report 8710, CERN Accelerator School, Fourth General Accelerator Physics Course, CERN Report 9104, M. Sands, The Physics of Electron Storage Rings, SLAC121, E.D. Courant and H.S. Snyder, Theory of the AlternatingGradient Synchrotron, Annals of Physics 3, 148 (1958). CERN Accelerator School, RF Engeneering for Particle Accelerators, CERN Report 92 03, CERN Accelerator School, 50 Years of Synchrotrons, CERN Report 9704, E.J.N. Wilson, Accelerators for the TwentyFirst Century A Review, CERN Report 9005, 1990.

5 Special Topics and Detailed Information: J.D. Jackson, Calssical Electrodynamics, Wiley, New York, Lichtenberg and Lieberman, Regular and Stochastic Motion, Applied Mathematical Sciences 38, Springer Verlag. A.W. Chao, Physics of Collective Beam Instabilities in High Energy Accelerators, Wiley, New York M. Diens, M. Month and S. Turner, Frontiers of Particle Beams: Intensity Limitations, SpringerVerlag 1992, (ISBN or ) (Hilton Head Island 1990) Physics of Collective Beam Instabilities in High Energy Accelerators, Wiley, New York R.A. Carrigan, F.R. Huson and M. Month, The State of Particle Accelerators and High Energy Physics, American Institute of Physics New Yorkm 1982, (ISBN ) (AIP ) Physics of Collective Beam Instabilities in High Energy Accelerators, Wiley, New York 1993.

6 I) Particle Acceleration Motivation Particle Sources Acceleration Concepts: Equations and Units DC Acceleration RF Acceleration Summary

7 Search for Elementary Particles Stage I: Nuclear Physics Chronology: 1803: 1896: 1896: Dalton M & P Currie Thomson Atom Atoms can decay Electron 1906: Rutherford Nucleus Electron 1911: Rutherford α N O H Disintegration of Nuclei! Particle Accelerators

8 Stage II: Particle Physics Chronology (Theory): 1905: Einstein 2 E = mc 1930: 1935: Dirac Yukawa Antimatter π Meson Chronology (Experiments): (Cosmic Rays) 1932: Anderson 1937: Anderson e µ p } π? Accelerators

9 Particle Sources: e : e Cathode Rays p : Cathode Tube withh H e H 2 e 2 2 H e H H e 2 H e H 2 e Antimatter: Pair Production

10 Acceleration Concepts Lorentz Force: dp dt = Q * ( E v x B ) Energy gain only due to E field! Scalar and Vector Potential: E = grad φ c 1 e e A t B = rot A Electrostatic fields (A = 0) Time varying fields ( = 0) φ

11 Units Energy Gain: 1 ev 19 (1.6 * 10 J) 1 Volt e E Common Units: kev, MeV, GeV, TeV ( ) 10, 10, 10, 10 Total Particle Energy: Relativity: 2 E = mc ; m = γ * m 0 γ = 1/ 1 β 2 ; β = v/c Electron: 31 m = 9.11*10 kg; MeV Proton: 27 m = 1.67*10 kg; GeV

12 Electrostatic Fields High Voltage Unit: ion source high voltage unit acceleration tube V = 200 kv max target Cascade Generator: 0 2U 4U 6U o o o U = U osin ωt capacitors diodes 1928: 1932: Cockroft Walton p Li 2 He (Nobel Prize 1951) 800kV 700kV (p)

13 Van de Graaf Generator Single Unit: charge collector charge conveyor belt 50 kv dc ion source spraycomb top terminal 10 MV evacuated acceleration channel spectrometer magnet experiment V = 10 MVolt max

14 Van de Graaf Generator Tandem generator: experiment pressure tank high voltage terminal negative ion Source striping foil or gas charge conveyor belt spraycomb 50 kv dc V = 25 MVolt max

15 Time Varying Fields E = 1 A c t e e E rot B = µε c e e E t capacitor beam AC generator Resonator: capacitor coil B L = C = ε 2 µ 0 N A l 0 d A beam E beam cavity f; Q; R cavity

16 Circular AcceleratorsI 1929: Lawrence Cyclotron Q ω = m B m v r = Q B m = const dee orbits f = const RF B = const beam extraction 1931: RF Livingston orbits H to 80 kev 1932: Lawrence p to 1.2 MeV (NP 1939)

17 Disadvantage: High Energy: γ >> 1 f = const. RF short bunch trains large dipole magnet Synchrotron: ω 0 = Q m r = m Q 0 0 B γ γ B v R = const. B = const. Small magnets, v = c f = const. RF

18 Circular Accelerators II Synchrotron: 1952: Cosmotron 3 GeV protons 1949: electrons injection magnet B RF cavity vacuum chamber extraction / target 1955: Bevatron 6 GeV protons p (fixedtarget experiment) 2 E E = 2 m c 1 1 cm 0 2 m c 2 0

19 Summary Acceleration Concept: Static field 25 MeV discharge AC field no limit length multiple passages Circular Acceleration: Cyclotron 25 MeV nonrelativistic Synchrotron no limit small magnets In Practice: Combination of several options