Particle Accelerators for Research and for Medicine

Transcription

1 Particle Accelerators for Research and for Medicine Prof. Ted Wilson (CERN and Oxford University) based on the book: ISBN This talk: 1

2 The race to high energies Rutherford fired the starting pistol At the Royal Society in 1928 he said I have long hoped for a source of positive particles more energetic than those emitted from natural radioactive substances. 2

3 The Large Hadron Collider (LHC) The LHC, at CERN, is the primary tool to which high-energy physicists are looking. The hope is to discover the Higgs particle. The machine is 28 km in circumference. 3

4 An exploded diagram of the ATLAS detector, for the LHC. 4

5 Wideroe invented the Linac Particle gains energy at each gap Lengths of drift tubes follow increasing velocity Spacing becomes regular as v approaches c 5

6 Cyclotron Magnet V dee ~ r + At all radii particles cross acceleration gap at same moment!

7 The 60-inch cyclotron. The picture was taken in

8 Spect diagnosis 8

9 Linacs an idea waiting for a technology Luis Alvarez Ed Ginzton 9

10 Induction Linacs The induction accelerator, FXR, at Lawrence Livermore, to study the behavior of the implosion process in nuclear weapons The Dual Axis Radiological Hydrodynamic Test Facility This device is to examine nuclear weapons from two axes to reveal departures from cylindrical symmetry which is a sign of aging. 10

11 The Synchrotron 11

12 First electron synchroton This 300 MeV electron synchroton at the General Electric Co. at Schenectady, built in the late 1940s. The photograph shows a beam of synchrotron radiation emerging. 12

13 Synchrotron Radiation Sources There are more than 50 synchrotron radiation facilities in the world. In the US there are machines in Brookhaven (NSLS), Argonne (APS), SLAC: SPEAR and the LCLS, and at LBL (ALS). This intricate structure of a complex protein molecule structure has been determined by reconstructing scattered synchrotron radiation 13

14 Linac Coherent Light Source and the European Union X-Ray Free Electron Laser (Fourth Generation) FELs, invented in the late 1970 s at Stanford are now becoming the basis of major facilities in the USA (SLAC) and Europe (DESY).They promise intense coherent radiation. The present projects expect to reach radiation of 1 Angstrom (0.1 nanometers, 10kilo-volt radiation) 14

15 10 12 Electrons 14 GeV Peak current > 1000A Transversely < 0.1 mm photons 0.15 < l < 1.5 nm Pulse: 100 femtoseconds down to 100 attoseconds Rate 120 Hz 1000 to times brighter than third generation Cost M$ 300 The SLAC site showing its two-mile long linear accelerator, the two arms of the SLC linear collider, and the large ring of PEPII. This is where the LCLS will be located. 15

16 Spallation Neutron Sources (SNS) 1GeV protons mean current 1 ma = 1.4 MW of power In a 0.7 microsecuond burs Cost is about 1.5 B$ An overview of the Spallation Neutron Source (SNS) site at Oak Ridge National Laboratory. 16

17 High temperature superconductor Crystal structure of the 90K YBa2Cu3O7 superconductor 17

18 Cancer Therapy Machines A modern system for treating a patient with x-rays produced by a high energy electron beam. The system, built by Varian, shows the very precise controls for positioning of a patient. The whole device is mounted on a gantry. As the gantry is rotated, so is the accelerator and the resulting x-rays, so that the radiation can be delivered to the tumor from all directions. 18

19 A drawing showing the Japanese proton ion synchrotron, HIMAC. The facility consists of two synchrotrons, so as to maintain a continuous supply of ions (or protons) to the treatment area. The pulse of ions is synchronized with the respiration of the 19 patient so as to minimize the effect of organ movement.

20 Ions Left is the phase diagram for the quark-gluon plasma Right is gold-gold collision in RHIC 20

21 Unstable Isotopes and their Ions The Rare Isotope Accelerator (RIA) scheme. The heart of the facility is composed of a driver accelerator capable of accelerating every element of the periodic table up to at least 400 MeV/nucleon. Rare isotopes will be produced in a number of dedicated production targets and will be used at rest for experiments, or they can be accelerated to energies below or near the Coulomb barrier. 21

22 Neutrino experiments Solar Neutrino Problem Super K K to K Gran Sasso Minos and NUMI Super Beams Neutrino Factories Muon Colliders Kamiokande This very large underground detector, located in the mountains of Japan. Many very important results have come from this facility that first took data in The facility was instrumental in solving the solar neutrino problem. 22

23 Basis of muon collider 23

24 Inertial confinement 24

25 Proton Drivers for Power Reactors A linac scheme for driving a reactor. These devices can turn thorium into a reactor fuel, power a reactor safely, and burn up long-lived fission products. 25

26 Oxford/LBNL Plasma-Laser Experiments: Guiding achieved over 33 mm: Capillary 190 um Input laser power 40 TW Peak input intensity > W cm -2 Plasma: cm -3 Spot size at entrance 26 μm Spot size at exit 33 μm W. P. Leemans et al. Nature Physics (2006) Butler et al. Phys. Rev. Lett (2002). D. J. Spence et al. Phys. Rev. E (R) (2001) Entrance Exit Plasma channel formed by heat conduction to capillary wall. E = (1.0 +/-0.06) GeV ΔE = 2.5% r.m.s Δθ = 1.6 mrad r.m.s. 26

27 The International Linear Collider (ILC) 27

28 CLIC A diagram showing the CERN approach to a linear collider. The two main linacs are driven by 12 GHz radio frequency power derived from a drive beam of low energy but high intensity that will be prepared in a series Engines of rings of Discovery combined with a conventional linac. 28

29 I have not mentioned Sterilisation Chip manufacture Art and archaeology National Security Surface treatment Etc. etc. 29

30 Accelerators bringing nations together The King of Jordan discussing with scientists the Sesame Project, which will be located in Jordan and available to all scientists. 30

31 Conclusion I have sketched for you some of the likely future projects of accelerator physics future. Perhaps, the development of accelerators was a passing moment in the history of mankind, but it is much more likely to be an activity that will continue, producing devices not only for physics, but for an ever increasing catalogue applications enriching our everyday lives. 31

32 Thank you for your attention. 32