Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 1 Lecture 2 - Overview of Accelerators II ACCELERATOR PHYSICS MT 2014 E. J. N. Wilson

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 2 Summary Lecture 1 - Overview of Accelerators I  The history of accelerators  Need for Accelerators  The race to high energies  Cockcroft and Walton - Electrostatic  Van der Graaf  Linear accelerator  Wideroe’s Linac  Fermilab linac (400MeV)  Inside the Fermilab linac  The Stanford Linear Accelerator  The International Linear Collider (ILC)  Cyclotrons –an inspired discovery  Magnetic Rigidity  Vertical Focusing  Discovery of the Synchrotron  Components of a synchrotron  Phase stability  Cosmotron  Weak focusing in a synchrotron

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 3 Lecture 2 – Overview II - Contents  The “n-value”  Weak focusing in a synchrotron  Cosmotron people  Strong focussing  CERN at BNL  CERN 25 GeV PS  CERNS RINGS  SPS  Center of mass v. Fixed target  AdA - The first collider e-plus-minus  ISR AND PS  Luminosity  SPS  Physics of the electron v. protons  LEP  Inside LEP  The Tevatron at FNAL  The Large Hadron Collider (LHC)  Superconducting magnets

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 4 Weak focusing in a synchrotron  Vertical focussing comes from the curvature of the field lines when the field falls off with radius ( positive n-value)  Horizontal focussing from the curvature of the path  The negative field gradient defocuses horizontally and must not be so strong as to cancel the path curvature effect The Cosmotron magnet

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 5  As the C magnet saturates the n value – which is the rate of droop – increases The “n-value”

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 6 Cosmotron people FOURGUYS.pct E.Courant -Lattice DesignerStan Livingston - Boss Snyder -theorist Christofilos - inventor

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 7 Strong focussing

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 8 CERN at BNL  Odd Dahl, Frank Goward, and Rolf Widerö  (right hand trio) Fig.3(CERNVISITORS).pct

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 9 CERN 25 GeV PS

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 10 CERNS RINGS

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 11 SPS

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 12 Center of mass v. Fixed target

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 13 AdA - The first collider e-plus-minus

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 14 ISR AND PS ISR+PS.pct

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 15  Imagine a blue particle colliding with a beam of cross section area - A  Probability of collision is  For N particles in both beams  Suppose they meet f times per second at the revolution frequency  Event rate Luminosity LUMINOSITY Make small Make big

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 16 SPS

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 17 Physics of the electron v. protons  When we collide Protons we collide complex assemblies of three quarks  Only two quarks interact  Their available energy is on average only 10% of the total centre of mass energy  We do not know which quarks they are  Hence in some ways 100 GeV LEP is as good as 1000 GeV TEVATRON HENCE THE RETURN TO LEP AFTER SPS AND THEN LHC AFTER LEP

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 18 LEP LEP(small).pct

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 19 Inside LEP

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 20 Superconducting magnets

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 21 Fermilab’s superconducting Tevatron can just be seen below the red and blue room temperature magnets of the 400 GeV main ring. The Tevatron at FNAL

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 22 The Large Hadron Collider (LHC)

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide CERN Control Centre – LHC Startup

Lecture 2 - E. Wilson 16 Oct 2014 –- Slide 24 Lecture 2 – Overview II - Contents  The “n-value”  Weak focusing in a synchrotronCosmotron people  Strong focussing  CERN at BNL  CERN 25 GeV PS  CERNS RINGS  SPS  Center of mass v. Fixed target  AdA - The first collider e-plus-minus  ISR AND PS  Luminosity  SPS  Physics of the electron v. protons  LEP  Inside LEP  The Tevatron at FNAL  The Large Hadron Collider (LHC)  Superconducting magnets