Accelerators Ken Peach John Adams Institute for Accelerator Science Charters School 28 th February 2007

Ken PeachJohn Adams Institute Outline Accelerators –Early Accelerators –Accelerators today Science –Particle Physics and Cosmology –Other sciences Society –Medicine Summary & Conclusions

Accelerators

Ken PeachJohn Adams Institute The 1 st Accelerator Experiment? Galileo Galilei ( ) (Probably apocryphal) Leaning Tower of Pisa –Use Leaning Tower of Pisa time to fall independent weight –Result? The Law of Gravity! Galileo Aristotle

Ken PeachJohn Adams Institute Lessons 1.Cost is significant 2.Limit to energy with the same technology 3.Higher energy needs a different approach not more of the “old” method Étienne & Joseph Montgolfier GalileoAristotle

Ken PeachJohn Adams Institute Cockcroft and Walton (UK) Early accelerator From the early days to The “Leaning” Cockcroft & Walton

Ken PeachJohn Adams Institute The Linear Accelerator (Linac) + - +

Ken PeachJohn Adams Institute The Linear Accelerator (Linac) Each voltage step is “modest” Inside a Linac The LEP Linear Injector Linac

Ken PeachJohn Adams Institute SLAC – The Stanford Linear Accelerator (Centre) 50 GeV electrons and positrons 2.8GHz RF 17MeV/m

Ken PeachJohn Adams Institute Lawrence (US) – the Cyclotron The Chicago Cyclotron Magnet Lawrence’s 1 st cyclotron

Ken PeachJohn Adams Institute The Cyclotron

Ken PeachJohn Adams Institute Lawrence (US) – the Cyclotron The Chicago Cyclotron Magnet Lawrence’s 1 st cyclotron

Ken PeachJohn Adams Institute Mark Oliphant and the Birmingham Synchrotron 1940s, Mark Oliphant designed and built a 1 GeV proton synchrotron at Birmingham (almost) the first working proton synchrotron in the world! (Just beaten by Berkeley) Mark Oliphant Oliphant also build a 400MeV cyclotron in Birmingham in the late 1930s

Ken PeachJohn Adams Institute CERN in Geneva (& France)

Ken PeachJohn Adams Institute LEP – the Large Electron-Positron Collider The Largest (electron) Synchrotron [so far!]

Science

Ken PeachJohn Adams Institute The equation of the Universe! (after Feynman) We know the equation of the Universe U = 1  U = 0 The trouble is, we have no idea what U is!!!! but … we know a lot about what U contains

Ken PeachJohn Adams Institute How to discover the structure of the Universe 3 basic ways Look at itHeat itSmash it Wavelength Temperature TEnergy E h c/ =kTE=

Ken PeachJohn Adams Institute Remarkable comment All three the same fundamental physics! Uses ‘light’ Uses ‘heat’ TUses ‘probe’ E h c/ =kTE= Photons ‘Photons’        

Ken PeachJohn Adams Institute The Big Bang BIG BANG

Ken PeachJohn Adams Institute LEP – the Large Electron-Positron Collider

Ken PeachJohn Adams Institute ALEPH A detector for LEP Physics © 

Ken PeachJohn Adams Institute Some events ‘evaporating from the vacuum’ Ze+e-Ze+e- Z+-Z+- Z   +  - Z  qq

Ken PeachJohn Adams Institute Some more (complicated) events Z   +  -  Z  qqg Z  4 ‘jets’ ZW+W-ZW+W-

Ken PeachJohn Adams Institute High Precision Frontier Known phenomena studied with high precision may show inconsistencies with theory High Energy Frontier New phenomena (new particles) created when the “usable” energy > mc 2 [×2] Accelerators for particle physics What is needed, and why 2 routes to new knowledge about the fundamental structure of the matter

Ken PeachJohn Adams Institute HiggsBoson HiggsBoson? Force Carriers Z Z boson W W boson  photon g gluon Generations of matter Generations of matter   -neutrino  tau b bottom t top III   -neutrino  muon s strange c charm II e e-neutrino e electron d down up uI Leptons Quarks The experimentalist’s view Each with its own ‘antiparticle’ © Brian Foster Particles and Forces

Ken PeachJohn Adams Institute What remains to be done? The Standard Model is a very good description of the Universe at the particle scale (~2M W ) –But does not explain many things Why so many particles? Why so many forces? What is mass? –Why do particles have the masses they have? How do neutrinos get mass? –Are neutrinos different? How do they fit in? What is Dark Matter? Dark Energy? Why is matter different from antimatter? –(Where did all the antimatter go?) Where does gravity fit in?

Ken PeachJohn Adams Institute The Large Hadron CERN 7,000,000,000,000 volt protons colliding head on 40,000,000 times per second protons What Happens?

Ken PeachJohn Adams Institute The Large Hadron CERN

Ken PeachJohn Adams Institute LHC machine status

Ken PeachJohn Adams Institute The Large Hadron Collider ATLAS CMS

Ken PeachJohn Adams Institute Status 16 th February 2006

Ken PeachJohn Adams Institute Status 23 rd February 2007

Ken PeachJohn Adams Institute What does the LHC hope to find? 1.The Higgs Boson –Complete the “Standard Model” –Confirm that we “understand” mass But perhaps not ! 2.Find something new –Clues to “Beyond the Standard Model” Towards a “Standard Theory” That Explains as well as Describes –Supersymmetry A new completely type of particle Could explain Dark Matter –Extra Dimensions We lives in 1 time + 3 out of n space dimensions! –The unexpected

Ken PeachJohn Adams Institute The Unexpected protons

Ken PeachJohn Adams Institute After the LHC? –What next? –Need to study the new discoveries –Precision measurements –History shows that –Proton colliders are good at discovery –e + e - colliders are good at precision measurement –Need higher energy than LEP –But synchrotrons at the limit –Synchrotron radiation –  E 4 at fixed radius –i.e. 2  Energy = 16  Power or 16  Radius! –Back to the Linac!!!!

Ken PeachJohn Adams Institute Why an e+e- collider? After Barry Barish  LEP LHC 

Ken PeachJohn Adams Institute A Linear Collider ~30 km!

Ken PeachJohn Adams Institute The heart of the Linear Collider

Other Sciences

Ken PeachJohn Adams Institute Accelerators for other sciences Neutron sources X-ray sources Nuclear Physics Accelerators for other applications Accelerators in Medicine

Ken PeachJohn Adams Institute RAL & Daresbury Built in the 1960s RAL 8 GeV proton synchrotron Daresbury 3 GeV electron synchrotron Both closed in the 1970s! –The UK’s accelerators were New projects from their ashes RAL 800MeV proton synchrotron for a Spallation Neutron Source Daresbury 2GeV Synchrotron Radiation Source } Particle Accelerators for other sciences (Physics, Chemistry, Engineering, Biology, Medicine)

Ken PeachJohn Adams Institute What is a Spallation Neutron Source? High Energy (~1GeV) High Power (~MW) (ISIS – 0.16MW) n n n n n nn n Target Protons

Ken PeachJohn Adams Institute RAL ISIS: 50 Hz 800 MeV 300 µA RAL 600 Experiments/year 1200 Users/year 235 UK Groups

Ken PeachJohn Adams Institute Neutron Scattering (ISIS)

Ken PeachJohn Adams Institute What is Synchrotron Radiation? Motion of a charged particle (an electron) in a magnetic field When ultra-relativistic, emits x-rays tangential to the motion X-ray

Ken PeachJohn Adams Institute Daresbury Sir John Walker, Nobel Prize in Chemistry, 1997 “for elucidation of the enzymatic mechanism underlying the synthesis of adenosine triphosphate (ATP)”

Ken PeachJohn Adams Institute Examples of use of Synchrotron Radiation CCLRC/SRD annual report

Ken PeachJohn Adams Institute Diamond & the ISIS 2 nd Target Station

Society Accelerators in Medicine Proton and Heavy Ion Therapy (not discussed: Accelerator Driven Reactors Accelerator Driven Transmutation of radioactive Waste)

Ken PeachJohn Adams Institute Incidence of Cancer in the UK 13.5% probability, all types (except skin cancer) –Around half are associated with specific risks –Statistically, some will be close to sensitive tissue And difficult to treat surgically or chemically Source: Cancer Research UK

Ken PeachJohn Adams Institute The Clatterbridge Centre for Oncology

Ken PeachJohn Adams Institute The Clatterbridge Centre for Oncology Established 1989 –First hospital based proton therapy –>1400 patients with ocular melanoma –First example of 3D computer treatment planning in UK; eye gaze direction used to obtain best approach angle to eye. Unsung success story of British Oncology! After Bleddyn Jones

Ken PeachJohn Adams Institute Why use protons? After Bleddyn Jones

Ken PeachJohn Adams Institute Single field opposed fields co-planar fields PROTONS X-Rays 2 opposed fields 3 co-planar fields Single field Depth % DOSE How does it work? After Bleddyn Jones

Ken PeachJohn Adams Institute X-Rays Protons Axial view 3 Field techniques After Bleddyn Jones

Ken PeachJohn Adams Institute Many centres world-wide based on information of the Particle Therapy Co-Operative Group (PTCOG)

Ken PeachJohn Adams Institute Hadron Therapy in Chiba (Japan) Stolen from Loma Linda Borrowed from Rob Edgecock

Ken PeachJohn Adams Institute Medical applications of accelerators Oncology –Protons, heavy ions, electrons Why so little interest in the UK? Preparation of radio-nuclides Requires precision control of –Energy –Dose Just like the linear collider (energy, luminosity)

Ken PeachJohn Adams Institute Summary and Conclusions Particle Accelerators are important tools –For Particle Physics (& cosmology) Science [and Society] will benefit –Science understanding the structure of (bio)materials –Society New and better materials New and better drugs New (and better?) therapies and they are fun too!