Accelerator Physics w w w Basic Formalism Linear

Accelerator Physics w w w Basic Formalism Linear Accelerators Circular Accelerators Magnets Beam Optics Our Accelerator Greg Le. Blanc Lead Accelerator Physicist Australian Synchrotron Project

Basic Formalism Lorentz Force w w Only works on charged particles Electric Fields for Acceleration Magnetic Fields for Steering Magnetic fields act perpendicular to the direction of motion. w For a relativistic particle, the force from a 1 Tessla magnetic field corresponds to an Electric field of 300 MV/m

Basic Formalism Energy w Rest Energy: w Relativistic Parameter: w Velocity: w Relativistic Mass: w Energy in e. V: (Electron rest mass 9. 1*10 -31 kg gives a rest energy of 511 ke. V)

Basic Formalism w Particles Relativistic when b 1

Linear Accelerators w w w Particles Accelerated in Straight Line Electrostatic or RF Fields Planar Wave Static Case Lorentz Force Energy Gain

Linear Accelerators Electrostatic Accelerators w Electron Gun w Van de Graaff generator (~20 MV)

Linear Accelerators w Wideroe n n RF Accelerators Long for low frequency Losses w Alvarez n n Higher frequency Higher voltages

Linear Accelerators w Travelling Wave w Standing Wave

Synchronicity in a LINAC The length of the ith drift tube is where is the velocity of the particles in the ith drift tube and is the rf period. Australian Synchrotron Example: Electrons at the speed of light (a valid approximation above 5 Me. V) in a 3 GHz linac

Circular Accelerators w Circular Motion in a Magnetic Field n Centripetal Force Lorentz Force n B, r or T constant n

Circular Accelerators w Cyclotron n n Constant B Non-relativistic

Circular Accelerators w Microtron n Synchronicity for Dg=integer n DEe=n x 511 ke. V n DEp=n x 938 Me. V w Race Track Microtron

Circular Accelerators w Synchrotron n Constant r and T Magnets ‘Ramped’ Storage Ring

Magnets Dipoles for Steering w Magnetic Field

Magnets Quadrupoles for Focusing w Gradient

Magnets w Sextupoles n Chromatic effects w Octupoles n Correcting Magnetic Errors

Beam Optics Coordinate System w Curvilinear System w Motion Relative Ideal Path individual particle trajectory s y S ideal path y x x r

Beam Optics w Particle motion determined by magnetic lattice w Studied using simulation software

Beam Optics w Machine Functions n n n Beam Motion Beam Size Beam Emittance

Beam Optics w Response Matrix n n Probe the Machine with the Beam Calibrate Models

Our Accelerator