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Transcript of Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL...
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Particle Accelerators: An introduction
Lenny RivkinSwiss Institute of Technology Lausanne (EPFL)
Paul Scherrer Institute (PSI)Switzerland
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
CERN
PSI
EPFL
CERN
PSI
EPFL
CERN
PSI
EPFL
CERN
PSI
EPFL
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
The Role of Accelerators in Physical and Life Sciences
“It is an historical fact that scientific revolutions are more often driven by new tools than by new concepts”
Freeman Dyson
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Particle beams: main uses(protons, electrons, photons, neutrons, muons, neutrinos etc.)
Research in basic subatomic physics
Analysis of physical, chemical and biological samples
Modification of physical, chemical and biological properties of matter
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Medicine35%
Industry60%
Research5%
Accelerators in the world
New technologies
New ApplicationsTotal number ~ 30’000growing at about 10% per year
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFLH. Dosch, DESY
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFLR. W. Hamm, 9th ICFA Seminar, October’08, SLAC
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
• High energy frontier
• High luminosity frontier
• High precision measurements
ACCELERATORS: INSTRUMENTS FOR PARTICLE PHYSICS
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Energy available in collisions (center-of-mass energy)
Fixed target geometry
Colliding beams
or for unequal energies
E
E E
EEcm 2
EmcEcm 22
212 EEEcm
Livingston plot
Equivalent energy of a fixed target accelerator
2
2
2mc
EE cm
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
BECAME THE MOST POWERFUL
ACCELERATOR FOR RESEARCH IN PARTICLE PHYSICS
IP
IP
COLLISION AT THE
IP (Interaction Point)
COLLIDERCIRCULAR
Luminosity
scmANf 2
2 1L
Interaction rate
int Ldtdn
R
Point cross-section
2int
1s
Unit: barn = 10 -24 cm2
1 fb
1 pb
History of luminosity in the world
1034cm-2s-
1=10 /nb/s
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Scaling of high energy proton rings
cGeVpmTB...29979.0
1
LEP tunnel: 1 TeV per 1 Tesla
Ecosts,
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Scaling of high energy electron rings
Electrons emit synchrotron radiation
2Ecosts,
2
4
PowerE2
4
cost
Eba
Ecosts :CollidersLinear
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Linear Colliders
30 – 40 kmRF in RF out
E
e+ e-
damping ring
main linac
beam delivery
rf power source
particles “surf” the electromagnetic wave
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL24
Tunnel implementations (laser straight)
Central MDI & Interaction Region
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
1 professional lifespan!
Beyound LHC? An 80 km tunnel?
John Osborne (CERN), Caroline Waaijer (CERN)
Magnetic field Energy c.o.m.
8.3 Tesla 42 TeV
16 Tesla 80 TeV
20 Tesla 100 TeV
Enrico Fermi’s (1954) Space-Based World Machine
Cosmic accelerators
Constellation Pictor: Pictor A X-ray imageX-ray jet originating near a giant black hole
800‘000 light years
Chandra X-Ray Observatory
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Useful books and references
H. Wiedemann, Particle Accelerator Physics I and IISpringer Study Edition, 2003
K. Wille, The physics of Particle Accelerators: An IntroductionOxford University Press, 2001
D. A. Edwards, M. J. Syphers, An Introduction to the Physics of High Energy AcceleratorsJohn Wiley & Sons, Inc. 1993
E.J.N. Wilson, An Introduction to Particle AcceleratorsOxford University Press, 2001
A. W. Chao, M. Tigner, Handbook of Accelerator Physics and Engineering, World Scientific 1999
CERN Accelerator School (CAS) proceedingsE. D. Courant and H. S. Snyder, Annals of Physics: 3, 1 - 48 (1958)M. Sands, SLAC-121
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
1980 James W. Cronin and Val L. Fitch
Cronin and Fitch concluded in 1964 that CP (charge-parity) symmetry is violated in the decay of neutral K mesons based upon their experiments using the Brookhaven Alternating Gradient Synchrotron [28].
1981 Kai M. Siegbahn Siegbahn invented a weak-focusing principle for betatrons in 1944 with which he made significant improvements in high-resolution electron spectroscopy [29].
1983 William A. Fowler Fowler collaborated on and analyzed accelerator-based experiments in 1958 [30], which he used to support his hypothesis on stellar-fusion processes in 1957 [31].
1984 Carlo Rubbia and Simon van der Meer
Rubbia led a team of physicists who observed the intermediate vector bosons W and Z in 1983 using CERN’s proton-antiproton collider [32], and van der Meer developed much of the instrumentation needed for these experiments [33].
1986 Ernst Ruska Ruska built the first electron microscope in 1933 based upon a magnetic optical system that provided large magnification [34].
1988 Leon M. Lederman, Melvin Schwartz, and Jack Steinberger
Lederman, Schwartz, and Steinberger discovered the muon neutrino in 1962 using Brookhaven’s Alternating Gradient Synchrotron [35].
1989 Wolfgang Paul Paul’s idea in the early 1950s of building ion traps grew out of accelerator physics [36].
1990 Jerome I. Friedman, Henry W. Kendall, and Richard E. Taylor
Friedman, Kendall, and Taylor’s experiments in 1974 on deep inelastic scattering of electrons on protons and bound neutrons used the SLAC linac [37].
1992 Georges Charpak Charpak’s development of multiwire proportional chambers in 1970 were made possible by accelerator-based testing at CERN [38].
1995 Martin L. Perl Perl discovered the tau lepton in 1975 using Stanford’s SPEAR collider [39].
2004 David J. Gross, Frank Wilczek, and H. David Politzer
Gross, Wilczek, and Politzer discovered asymptotic freedom in the theory of strong interactions in 1973 based upon results from the SLAC linac on electron-proton scattering [40].
2008 Makoto Kobayashi and Toshihide Maskawa
Kobayashi and Maskawa’s theory of quark mixing in 1973 was confirmed by results from the KEKB accelerator at KEK (High Energy Accelerator Research Organization) in Tsukuba, Ibaraki Prefecture, Japan, and the PEP II (Positron Electron Project II) at SLAC [41], which showed that quark mixing in the six-quark model is the dominant source of broken symmetry [42].
Year Name Accelerator-Science Contribution to Nobel Prize-Winning Research
1939 Ernest O. Lawrence Lawrence invented the cyclotron at the University of Californian at Berkeley in 1929 [12].
1951 John D. Cockcroft and Ernest T.S. Walton
Cockcroft and Walton invented their eponymous linear positive-ion accelerator at the Cavendish Laboratory in Cambridge, England, in 1932 [13].
1952 Felix Bloch Bloch used a cyclotron at the Crocker Radiation Laboratory at the University of California at Berkeley in his discovery of the magnetic moment of the neutron in 1940 [14].
1957 Tsung-Dao Lee and Chen Ning Yang
Lee and Yang analyzed data on K mesons (θ and τ) from Bevatron experiments at the Lawrence Radiation Laboratory in 1955 [15], which supported their idea in 1956 that parity is not conserved in weak interactions [16].
1959 Emilio G. Segrè and Owen Chamberlain
Segrè and Chamberlain discovered the antiproton in 1955 using the Bevatron at the Lawrence Radiation Laboratory [17].
1960 Donald A. Glaser Glaser tested his first experimental six-inch bubble chamber in 1955 with high-energy protons produced by the Brookhaven Cosmotron [18].
1961 Robert Hofstadter Hofstadter carried out electron-scattering experiments on carbon-12 and oxygen-16 in 1959 using the SLAC linac and thereby made discoveries on the structure of nucleons [19].
1963 Maria Goeppert Mayer Goeppert Mayer analyzed experiments using neutron beams produced by the University of Chicago cyclotron in 1947 to measure the nuclear binding energies of krypton and xenon [20], which led to her discoveries on high magic numbers in 1948 [21].
1967 Hans A. Bethe Bethe analyzed nuclear reactions involving accelerated protons and other nuclei whereby he discovered in 1939 how energy is produced in stars [22].
1968 Luis W. Alvarez Alvarez discovered a large number of resonance states using his fifteen-inch hydrogen bubble chamber and high-energy proton beams from the Bevatron at the Lawrence Radiation Laboratory [23].
1976 Burton Richter and Samuel C.C. Ting
Richter discovered the J/ particle in 1974 using the SPEAR collider at Stanford [24], and Ting discovered the J/ particle independently in 1974 using the Brookhaven Alternating Gradient Synchrotron [25].
1979 Sheldon L. Glashow, Abdus Salam, and Steven Weinberg
Glashow, Salam, and Weinberg cited experiments on the bombardment of nuclei with neutrinos at CERN in 1973 [26] as confirmation of their prediction of weak neutral currents [27].
24 Nobel Prizes in Physics that had direct contribution from accelerators
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
19 Nobels with X-rays
Chemistry1936: Peter Debye1962: Max Purutz and Sir John
Kendrew1976 William Lipscomb1985 Herbert Hauptman and
Jerome Karle1988 Johann Deisenhofer, Robert
Huber and Hartmut Michel1997 Paul D. Boyer and John E.
Walker2003 Peter Agre and Roderick
Mackinnon2009 V. Ramakrishnan, Th. A.
Steitz, A. E. Yonath
Physics1901 Wilhem Rontgen1914 Max von Laue1915 Sir William Bragg and son1917 Charles Barkla1924 Karl Siegbahn1927 Arthur Compton1981 Kai Siegbahn
Medicine1946 Hermann Muller1962 Frances Crick, James
Watson and Maurice Wilkins1979 Alan Cormack and Godfrey
Hounsfield
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Light sources
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
60‘000 users world-wide
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
The “brightness” of a light source:
Flux, F
FS x W
Brightness = constant x _________
Angular divergence, W
Source area, S
Steep rise in brightness
1021
1015
109
1900 1950 2000
Wigglers
Bending magnets
Undulators
Rotating anode
SPring8
ESRF
APS
Bertha Roentgen’s hand(exposure: 20 min)
Moore’s Law for semiconductors
SLSSOLEIL (F)DIAMOND (UK) …
the second wave
XFEL
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
The electron beam “emittance”:
Emittance = S x W
Angular divergence, W
Source area, S The brightness
depends on the geometry of the source, i.e., on the electron beam emittance
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Medical applications
Protons – treatment of tumors
improved radiation therapy> 800 patients treated with deep-seated tumors> 5800 patients treated with eye tumors
> 50 % of patients are below 40 years old
25%
12%
15%14%
13%
14%
7%
<20
21-30
31-40
41-50
51-60
61-70
>70
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
BRAGG PEAK
PROTON BEAM
… ALLOWS THE TREATMENT OF DEEP INSIDE LYING TUMORS WITH BEST
PROTECTION OF THE SURROUNDING
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Comparison of Characteristics of Photons und Protons for Radiation Therapy
Tumor
Depth (cm)
Dose
SPOT SCANNING
ENERGY
PO
SIT
ION
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
GANTRY
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Aim of proton therapy: Dose concentrated in the tumor volume,low dose or no dose to healthy tissues
Protons IMRT -Photons
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
First accelerators
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Electrostatic linear accelerator
SLS DC electron gun: U = 90 kV, Ek = 90 keV
U- +
CATHODE
2
vm 1)(γcm EeU
2o2
ok non-relativistic approxim.
COCKROFT WALTON
VAN DE GRAFF
TANDEM
PELLETRON
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
First accelerators:Cockcroft and Walton 1932
MeV2.177 pLi
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Going beyond 1 MV
Can we repeat the process of DC acceleration?
Need time varying fields
tV
tV
t
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Wideroe Linac 1928Wideroe Linac 1928
Drift tubesIon source Acceleration of slow ions
RF TransmitterfRF ~ 1–7 MHz
Beam
04.0
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
FOR THE SAME ENERGY EXTRACTED FROM THE FIELD,
A PARTICLE WITH LOWER MASS IS MORE RELATIVISTIC
v/c
eU [MeV]0
0.2
0.4
0.6
0.8
1
0.001 0.01 0.1 1 10 100 1000 10000
c
v
2
11
v
c
e p
oE
eU1
U- +
CATHODE
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
FERMILAB
ALAVAREZ DTL
The drift tubes are enclosed in a single resonant tank in order to avoid large radiative energy losses at higher frequencies (e.g. 200 MHz)
ALVAREZ LINACS WORK UP TO b ~ 0.4
A NEW STRUCTURE IS REQUIRED FOR RELATIVISTIC PARTICLES !
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Electron RF linacs
Disk loaded accelerating structure slows down the RF wave to let electron keep up with it
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
SLS 100 MeV RF linac
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Lawrence: coiled up linac
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
First accelerators: cyclotron
Livingston and Lawrence4.5 inch model cyclotron27 inch cyclotron
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
First accelerators: cyclotron
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Rolf Wideröe‘s notebook
Introduction to Accelerators, African School of Physics, KNUST, Kumasi, Ghana; L. Rivkin, PSI & EPFL
Donald Kerst: first betatron (1940)
"Ausserordentlichhochgeschwindigkeitelektronenentwickelndenschwerarbeitsbeigollitron"