1 Diamond RAL Particle Physics Masterclass 12 March 2003 Glenn Patrick

2 DIAMOND Synchrotron Third Generation Light Source. To be built at RAL. Start of operation = Cost = £235M. Studies at molecular/atomic level. Ground-breaking - Wednesday 12th March! e

3 You are here

4 Storage ring circumference = 560m Control Room Research Building Shielding Operations Linac & Booster

5 Energy = 3 GeV Energy = 100 MeV Beam Lifetime 10 hours Current = 300 mA 1 MeV=1 x 10 6 eV 1 GeV=1 x 10 9 eV 1 TeV=1 x eV Electron volt is energy given to an electron accelerated through potential difference of 1 volt.

6 Force on charged particle is given by Lorentz Force Charged Particle Beams Acceleration Bending

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8 RF Cavities Radiofrequency (RF) Cavities Provide the acceleration energy. DIAMOND cavities will be based on superconducting niobium. In the same way that waves propel surfers, EM waves accelerate particles. Beam Pipe/Vacuum chamber Beams circulate in highly evacuated vacuum pipe to avoid loss of beam by collision with air molecules DIAMOND has a base pressure of ~ torr. LEP vacuum was torr – a world record! ISR LEP LHC

9 p=momentum in GeV/c B=magnetic field in Tesla R=bending radius in m Bending Magnets

10 Synchrotron Radiation e Synchrotron Radiation Energy loss per revolution Choose electrons because they are the lightest charged particle First observed in a circular accelerator in 1947 (General Electric, New York). Seen naturally when charged particles spiral around magnetic field lines in space. SRS at Daresbury (Cheshire) was worlds first dedicated high-energy radiation source.

11 Galaxy 3C 66B 10,000 light year jet of plasma - emitting synchrotron radiation Electrons spiralling along magnetic field lines. Hubble Space Telescope, 1991

12 LEP Sextupole Correction of chromatic spread. Focussing Magnets LEP Quadrapole Strong Focussing Beam alternately focussed in horiz and Vert planes.

13 Insertion Devices Can increase flux & brightness of light from normal bending magnets many thousands of times by using insertion devices. Rows of small magnets which jiggle the electron beam causing it to emit more radiation. Positioned on straight sections of the storage ring. Wiggler Undulator

14 Probing Matter Shorter wavelengths means higher energies.

15 Beamlines Diamond will be the best medium energy source in the world and is optimised to provide X-rays with energies from 100 eV up to 20 keV. Initially 7 beamlines, but room for 30 or more

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17 Finally - Science! Protein Cystallography Foot & Mouth Virus Muscle Structure Polypropylene diffraction Enzyme StructureLithium niobate diffraction