1. Introduction to particle accelerators
Walter Scandale
CERN - AT department
Lecce, 17 June 2006

2. Particle accelerators are black boxes producing
Introductory remarks
Particle accelerators are black boxes producing
either flux of particles impinging on a fixed target
or debris of interactions emerging from colliding particles
In trying to clarify what the black boxes are one can
list the technological problems
describe the basic physics and mathematics involved
Most of the phenomena in a particle accelerator can be described in terms of classical mechanics and electro-dynamics, using a little bit of restricted relativity
However there will be complications:
in an accelerator there are many non-linear phenomena (stability of motion, chaotic single-particle trajectories)
there are many particles interacting to each other and with a complex surroundings
the available instrumentation will only provide observables averaged over large ensembles of particles
In two hours we can only fly over the problems just to have an overview of them

3. Inventory of synchrotron components

4. Bending magnet Efficient use of the current -> small gap height
Field quality -> determined by the pole shape
Field saturation -> 2 Tesla BEarth = Tesla
B > 2 Tesla -> use superconducting magnets BLHC = 8.4 Tesla

5. Quadrupole magnet Vertical focusing Horizontal defocusing
g=gradient [T/m]

6. Alternate gradient focusingQF QD

7. Mechanical analogy for alternate gradient

8. Basic 2-D equation of motion in a dipolar field

9. Basic 2D equation of motion

10. Basic 2D equation of motion
FODO structure
Periodic envelop
Cos-like trajectory
Sin-like trajectory
Multi-turn trajectory

11. Longitudinal stability
Momentum compaction

12. Chromaticity and sextupole magnet
Dispersion orbit

13. Chromaticity correction and non-linear resonance

14. Emittance

15. Synchrotron radiation

16. Synchrotron radiation and beam size
Adiabatic damping
Synchrotron light emission

17. Effect of synchrotron light

18. Collective effects

19. Instabilities and feedback

21. Space charge

22. Beam size

23. Fixed target versus collider rings
Advantage
Collider
Bruno Touschek

24. Lepton versus hadron colliders
->
(At the parton level )
->

25. Lecture II

26. LHC lay-out C = 26658.90 m Arc = 2452.23 m DS = 2 x 170 m
INS = 2 x 269 m
Free space
for detectors:  23 m

27. LHC features
Technological
challenge
(+1)

28. e* = m
Bunch spacing
25 ns m

29. Maximum B-field

30. Cos(q) coil

31. Superconducting dipole

32. Collider luminosity
High L needs:

33. Beam-beam interaction

34. Head-on collisions

37. LHC luminosity

38. LHC insertions
56 m

42. High luminosity experiments

43. Ion-ion experiment