Introduction to Accelerators Overview

Saturday Morning Physics Fermilab – October 18th Particle accelerators

Particle accelerator is a device that uses electrostatic force to accelerate and electromagnetic fields to bend charge particles to high speeds and energy

SMP - Introduction to Accelerators | fgg 2 What is a particle accelerator? Does anyone knows what . World’s biggest particle accelerator the name of this machine is? . 7 TeV energy , 17 miles (27 km) in circumference . 574 ft (~180 m) buried underground between the border of France and Switzerland

heat matter at temperatures last seen since Big Bang

LHC: Ulra High vacuum Order the magnitude lower than ISS space station

Very low temperatures -456o F

SMP - Introduction to Accelerators | fgg 3 How many accelerators are there?

There are > 15,000 particle accelerators around the world

Only research particle accelerators are shown here. Data: ELSA [http://www-elsa.physik.uni-bonn.de/accelerator_list.html]

SMP - Introduction to Accelerators | fgg 4 How do they work? Which of these particles you cannot put into an accelerator? Required elements to make an accelerator Particles Energy Control Collision Detector

e n p g l e r o e u o l c t t d t r o r o n a o n t n o m SMP - Introduction to Accelerators | fgg 5 Particle accelerators

Modern Physics Computing Quantum Physics Accelerator design code Particle Physics High performance computing

Engineering Radio Frequency Classical Physics Alignment & Survey Ultra high vacuum Mechanics Particle Electronics Electrodynamics Accelerator Magnet Technology Mechanical Cryogenics

SMP - Introduction to Accelerators | fgg 6 A little bit about me… This is Originally from Sao Paulo (USP), Brazil great… What do I like… BRR!!! soccer, football, F1, ski, hiking, camping, Fermilab… relax on the beach…21F Here I come! Interval training workout Movies, concerts, plays, operas

~8,400Education miles – University later of Sao Paulo 1995 Ms in Theoretical Particle Physics 2000 PhD in Exp. Particle Physics 84F Feb ‘96 moved to US to develop my PhD work

SMP - Introduction to Accelerators | fgg 7 Outline

1. INTRODUCTION 1. HISTORY OF ACCELERATORS 2. BEAM CONTROL 1. STEERING 2. FOCUSING 2. FNAL ACCELERATORS CHAIN 1. ACCELERATOR BASED EXPERIMENTS 2. BEAM DIAGNOSTICS 3. RADIATION 4. HOW ACCELERATORS ARE OPERATED 3. ACCELERATOR APPLICATIONS, TECHNOLOGY & FUTURE ACCELERATOS

SMP - Introduction to Accelerators | fgg 8 Particle accelerators

Modern Physics Computing Quantum Physics Accelerator design code Particle Physics High performance computing

Engineering Radio Frequency Classical Physics Alignment & Survey Ultra high vacuum Mechanics Particle Electronics Electrodynamics Accelerator Magnet Technology Mechanical Cryogenics

SMP - Introduction to Accelerators | fgg 9 Units .Energy is measured in units of electron volt (eV) . 1 eV : kinetic energy gained (or lost) by a unit charged particle after crossing an electrical potential of one volt

. However, 1V = 1 J/C , so 1eV = (1.602x10-19 C)*1 J/C DE = qV How fast is the particleelementary moving? particle 1 E = mv2 , so v = 2퐸/푚 + V=1.5V - 2 INTRODUCTION = 2푥1.5푥(1.6푥10−19퐽)/(1.67푥10−27푘푔) ≌ 1.7푥104 푚/푠 remember that velocity of light is 3x108 m/s this is only 0.006 of speed of light!!!

SMP - Introduction to Accelerators | fgg 10 Electrostatic

The force from the electrical field will pull How many batteries would take to the particle and make it create a LHC accelerator? move increasing its speed

INTRODUCTION until it moves really fast.

So…does it mean that particles will be moving at

7푥1012 NO! relativistic effects Not very practical, is it? ≃ 4,000c??? 1.5 has to be considered (more later…) SMP - Introduction to Accelerators | fgg 11 Electromagnetism

When a charge particle is placed in a magnetic field, it experiences a magnetic force when the charge is moving relative to the magnetic field

퐹 퐵 (perpendicular)

푣 INTRODUCTION 퐵 Magnetic field make particles to move on a circular path

SMP - Introduction to Accelerators | fgg 12

Electrostatic & Electromagnetism

While electric fields change the energy of the particles, Magnetics fields make them making the particles move follow a circular path Lorentz INTRODUCTION faster …. Equation of motion under Lorentz force 푑푝 퐹 = 푑푡 = q(퐸 + 푣 x퐵)

SMP - Introduction to Accelerators | fgg 13 Relativity: momentum & energy

Rest energy = 푚 푐 2 2 E0 0 Einstein’s relativity formula E = 푚푐 E Lorentz factor g = E mass of a moving 0 When particles are accelerated close to speed particle 푚 = g푚0 v of light, relativistic effects start counting... Normal veloci b = ty c Total Energy

2 2 2 2 2 2 2 E pc E = Ekin + m0c = 푚0푐 + 푝푐

INTRODUCTION E E0 pc E0 momentum and energy are not equal Non-relativistic p = m v p = 푚푣 = 푚0푐bg 0

E momentum and energy become closer pc High relativistic p = m0cg = E/c

E0 SMP - Introduction to Accelerators | fgg 14 Length scale …why accelerators?

In order to study small objects, the higher the energy of the probe one needs to use it ℎ De Broglie’s wavelength l = Planck constant h = 6.63x10−34J.s 푝

= 4.14x 10−15eV.s INTRODUCTION

Picture from http://www.clab.edc.uoc.gr/materials/pc/surf/ accelerators_intro.html

SMP - Introduction to Accelerators | fgg 15

Velocity as function of energy

E= 훾푚푐2

relativistic More energy can be poured into the 2∗퐸 v= particles, giving a shorter l so that it 푚 Non-relativistic probes deeper into the sub-atomic world

INTRODUCTION [MeV]

SMP - Introduction to Accelerators | fgg 16 Early days…

. 1870 Discovery of Cathode Rays Tube (CRT) by William Crookes . Propagation of electrons from the cathode to the anode

William Crookes

Electrons are emitted from a heated

element (cathode) which resides inside INTRODUCTION glass tube under vacuum. Electrons are attracted to the anode and strike a flat screen coated with phosphor which glows Where was it used for? when struck by the beam of electrons Typical energies of about tens of thousands of eV

SMP - Introduction to Accelerators | fgg 17 Early days… . 1895 Discover of X-Rays

. X-rays are produced as the result Nobel Prize of changes in the positions of the 1901

electrons orbiting the nucleus An X-ray tube: electrons are accelerated by electrical field Wilhelm Rontgen and generate X-rays when they First X ray made in public. Medical hit a target. Society Jan 1896 INTRODUCTION . 1897 – Cavendish Laboratory . Demonstrates that cathode rays are made of particles . measured the mass to charge ratio, . 1,800 x lighter than hydrogen atom . Discovery of the first elementary particle electron

SMP - Introduction to Accelerators | fgg 18 Timeline

1890 Rutherford develops the theory of atomic scattering using alpha-particles Rutherford need a more powerful source to 1900 continue his research

Direct-Voltage accelerators 1927: “It has been my ambition to have Cockcroft & Walton & Van de Graaf available for study a copious supply of atoms electrostatic generator and electrons which have an individual 1930 1928 Gurney and Gamov predicted tunneling energy far transcending that of alpha and & Cockcroft-Walton start designing 800kW beta particles from radioactive bodies. I am hopeful that I may yet have my wish fulfilled.”

1940

SMP - Introduction to Accelerators | fgg 19 Cockcroft-Walton accelerator

1928-1930 Rutherford’s Laboratory . Nobel Prize . Voltage multiplier by using a stack of1951

capacitors and switch diodes Design for 800 kV, but reached 700kV John Cockcroft E.T..S. Walton Lithium atoms split with only 400 kV protons! First device to produce an artificial nuclear disintegration

Main limitation INTRODUCTION Hard to reach ~1MV due to discharges through air and along material surfaces.

Concept design First accelerator John Cockcroft , Ernest Rutherford, E.T..S. Walton SMP - Introduction to Accelerators | fgg 20

Examples of C-W accelerators

BNL (USA) 1971-1988

INTRODUCTION CERN (CH-F) 1959-1993

FNAL (USA) 1969-2012

SMP - Introduction to Accelerators | fgg 21 The Van de Graaf generator

. 1929-1933 VDG . Belt of insulating material carries electricity from a point source to a large insulated spherical

conductor. Another belt delivers electricity of the opposite charge to another sphere Concept design R. J. Van de Graaff Main limitation . Tandem Graaf Accelerator (1950) Van de Graaf cannot go . Negative ions are accelerate towards a much beyond 10-20 MV. positive terminal located

INTRODUCTION Electric breakdown in the center of a pressure tank was a . The negative ions pass through a foil the electrons fundamental are stripped, producing a limitation. positive-ion beam . The beam is then accelerated a second time away from the positive terminal

SMP - Introduction to Accelerators | fgg 22

Examples of VDG & Tandem generators

Daresbury (UK) 20MeV 1981 MIT (USA) 5MV generator 1933

INTRODUCTION 14UD 15MV ANU (Australia) Operational since 1973

Michigan (USA) 6MV Tandem Yale (USA) 1964-2011 22.4 MV Tandem BNL (USA) 15MV Fermilab (USA) SMP - Introduction to Accelerators | fgg 4.4 MV Pelletron23 Timeline

1890 Rutherford develops the theory 1927: “It has been my ambition to have of atomic scattering available for study a copious supply of atoms Rutherford need a more powerful source to and electrons which have an individual continue his research. 1900 energy far transcending that of alpha and beta particles from radioactive bodies. I am hopeful that I may yet have my with fulfilled.”

Direct-Voltage accelerators Time-varying fields resonant acceleration Cockcroft & Walton & Van de Graaf electrostatic generator 1930 1924 Ising proposes time-varying fields 1928 Gurney and Gamov predicted tunneling across drift-tubes & Cockcroft-Walton start designing 800 kW 1928 Wideroe demonstrates Ising’s principle 1929 Lawrence creates cyclotron

1940

SMP - Introduction to Accelerators | fgg 24 Application of time-varying fields

. 1924 Gustav Ising, (Sweden) . proposes applying much smaller voltage in an linear

accelerator by using time-varying fields

G. Ising Particles would be accelerated by using alternating electric fields, with “drift tubes” INTRODUCTION positioned at appropriate Ising’s idea intervals to shield the particles during the half-cycle when the Ising was unable to field is in the wrong direction demonstrate the concept for acceleration

SMP - Introduction to Accelerators | fgg 25 .. Wideroe first linear accelerator . 1927 Wideroe.. (Aachen, Germany) built first linac . Influenced by Ising’s 1924 paper . Particles acquire small energy increment with by repeatedly

transverse the same accelerating field

.. Beam accelerated to 50 keV R. Wideroe

Potassium source 25 kV, Resonance Acceleration 1MHZ crucial technology

INTRODUCTION Note: The drift tube length has to AC voltage increase because particles are not yet relativistic. Particle has to travel more in the shielded region

to be in phase with the

-

accelerating field - - -

SMP - Introduction to Accelerators | fgg 26 .. Wideroe linear accelerator…BUT

푣 . Period length increase with velocity l= 2푓 . Wideroe.. linac was good for low-energy heavy ions When using low frequency, the length of the drift tube becomes . prohibited for high energies . Higher frequency power sources were unavailable until after WWII e. g. 10 MHz proton accelerator

INTRODUCTION Main limitations At higher energy, the drift tube length is too long High RF frequency > 10 MHz higher power loss

SMP - Introduction to Accelerators | fgg 27 INTRODUCTION Alvarez drift tube tube drift linac Alvarez cooling inside for on The generators high resonant enclosed The .

tube linac Alvarez(USA1947 stems

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the SMP accelerated protonsfromMeV 4to32 accelerated whichof 201.25MHz frequency 1 -

m diameter, 12 m diameter, -

Introductionto Accelerators | fgg - m long witharesonant

퐵

퐸

L. W.L. Alvarez 28

Examples of Alvarez DTL linac

FNAL Linac 400 MeV 200 MHz CERN Linac 1 50 MeV

INTRODUCTION (40+ years of Operation) (33 years operational retired in 1992)

DESI 988 MeV LINAC III GSI LINAC (Germany) (Germany)

SMP - Introduction to Accelerators | fgg 29 Cyclotron accelerator

. 1930 Berkeley Nobel Prize . particles circulate in a static 1939 magnetic field which held the particles to a spiral trajectory and E. O. Lawrence pass one and the same accelerating gap several times First original cyclotron Typical max energy : 20 MeV (proton) INTRODUCTION Main limitation Does not work with relativistic particles Magnetic field at large radius not vertical Animation from AIP SMP - Introduction to Accelerators | fgg 30 Cyclotron principle

. For a particle that moves perpendicular to the magnetic field 퐹 = 푚풂 = 푞풗푩 . Non-relativistic uniform circular motion is maintained via 2

푚푣 centripetal acceleration = 푞푣퐵 푚푣 푟 . Radius is 푟 = 푞퐵 2휋푟 2휋푚 . Revolution period is given by 푇 = = The  is independent of speed 푣 푞퐵 2휋 푞퐵 and energy of the particle . Revolution angular frequency is ω = = 푇 푚 When the particle E & 푣 ↑ they INTRODUCTION What is the radius of revolution for travel with a larger radius in the a 100 GeV proton in a B=2T field? magnetic field

2 2 2 2 2푚 퐾 −27 −8 푚푣 푅 푞 퐵 푚푎푥 2 푥 1.66푥10 푥 1푥10 K = = R = 2 2 = = 18 m max 2 2푚 max 푞 퐵 1.6푥10−19 2 푥 4 Very costly to build a magnet of this extend… for higher energy the radius would be in km!! SMP - Introduction to Accelerators | fgg 31

Examples of cyclotron accelerator

Berkeley (USA) 11-inch – 1.1 MeV “The Crock” 60-inch Berkeley 60-inch cyclotron - Berkeley INTRODUCTION

TRIUMP (Canada) 520 MeV (rare isotope)

SMP - Introduction to Accelerators | fgg 32 Timeline 1927: “It has been my ambition to have 1890 available for study a copious supply of atoms Rutherford develops the theory and electrons which have an individual of atomic scattering energy far transcending that of alpha and Rutherford need a more powerful source to beta particles from radioactive bodies. I am continue his research. 1900 hopeful that I may yet have my with fulfilled.”

Direct-Voltage accelerators Time-varying fields resonant acceleration Cockcroft & Walton & Van de Graaf electrostatic generator 1930 1924 Ising proposes time-varying fields 1928 Gurney and Gamov predicted tunneling across drift-tubes & Cockcroft-Walton start designing 800 kW 1928 Wideroe demonstrates Ising’s principle 1929 Lawrence creates cyclotron

1945 McMillan and Veksler Phase stability 1940 1952 Courant, Livingston and Snyder propose strong focusing

SMP - Introduction to Accelerators | fgg 33 Principle of phase stability

. 1945 McMillan and Veksler independent discovered the principle of phase stability . adjusting the frequency of the applied voltage, particles were possible to accelerate to several hundred of MeV V. Veksler E. McMillan . these machines can only accelerate a single bunch of particles How does phase stability work? Particle P arrives in a gap in advance as INTRODUCTION compared to M1 will get less energy and its velocity will be smaller, so it will take more time to travel. Particle P’ arrives late in a gap compared to M1 will get more energy and its velocity will be larger so it will take less time to travel. SMP - Introduction to Accelerators | fgg 34 The synchrotron accelerator

. The synchrotron is a synchronous accelerator since there is a synchronous phase for which the energy gain fits the

increase in magnetic field at each turn

1952 - First synchrotron L. Oliphant V 3-GeV BNL Cosmotron Components of a Synchrotron

INTRODUCTION bending magnets Extraction . In a synchrotron the bending magnetic magnets field is time-dependent. RF cavity . As particles accelerate, the B field and the frequency of the RF has to Injection magnets “weak focusing” vary proportionally SMP - Introduction to Accelerators | fgg 35 Harmonic number & circumference

ring circumference: 휆푠 . the accelerating gap is shorter than the length of the RF bucket: 휆푅퐹 g ≪ 푣푇푅퐹 = distance traveled by the particle during 휆 푣 푅퐹 = 훽휆 h=1 one RF period TRF 푐 푅퐹 the RF angular frequency is an integer

. multiple of the angular revolution h=2 frequency 휔푅퐹 = h휔푠 푓푅퐹 = ℎ푓푠 푐 ℎ푐 h=4 = 휆푠= h휆푅퐹 휆푅퐹 휆푠 Hmm….I see…what is it again? INTRODUCTION Let’s take a look at the FNAL/Booster Impress your friends - Bucket is a RF structure 푃푎푟푎푚푒푡푒푟푠: 푓 = 53푀퐻푧, r = 75m 푅퐹 without beam 3푥108 푚/푠 - Bunch is a RF bucket 휆푅퐹 = 6 = 5.66 푚 53푥10 1/푠 with beam 휆푠 = 2. 휋. 푟 = 471.23 푚 - Batch is a multiple # of 휆푠 bunches 푠표 ℎ = = 84 휆푅퐹 SMP - Introduction to Accelerators | fgg 36 If life was that easy… . In an ideal world, a particle in an accelerator would happily circulate on axis of the machine forever

. what happens if the particle is deflected on the H/V plane?

푩 푩

INTRODUCTION Horizontal plane remains stable Vertical plane spirals away

Possible causes: Machine misalignment, error in magnet strength, energy error of particles, etc…

SMP - Introduction to Accelerators | fgg 37 If life was that easy…

. Most of the particles in the beam are not ideal particles . Sooner or later these particles will hit the walls of the vacuum chamber and be lost

sort likely a flashlight beam, spreading out away from the source INTRODUCTION How can we keep these particles within the vacuum chambers?

SMP - Introduction to Accelerators | fgg 38 Alternate gradient focusing . 1952 strong focusing was proposed by Courant, Livingston and Snyder which revolutionized synchrotron design E. Courant (left) . A way of increasing the energy without increasing the M. Livingston, size of the machine H. Snyder . Consist of an array of magnets with alternating focusing to give stability to the particle beam . First applied to 1.2 GeV electron synchrotron INTRODUCTION bending focusing at Cornell University in 1954 magnets Extraction magnets . Modern application used separated-function magnets magnets . “Optical” magnetic elements provides focusing RF cavity (later…) Injection magnets SMP - Introduction to Accelerators | fgg 39

Example of synchrotron accelerator

FNAL/Booster 8 GeV (1970-present) FNAL/Main Injector 120 GeV (1998-present) INTRODUCTION

FNAL/Tevatron

FNAL/Tevatron 980 GeV (1983-2011) CERN/SPS 450 GeV (1976-present) SMP - Introduction to Accelerators | fgg 40 Particle accelerators

Modern Physics Computing Quantum Physics Accelerator design code Particle Physics High performance computing

Engineering Radio Frequency Classical Physics Alignment & Survey Ultra high vacuum Mechanics Particle Electronics Electrodynamics Accelerator Magnet Technology Mechanical Cryogenics

SMP - Introduction to Accelerators | fgg 41 Dipole magnets

Lorentz Force Centripetal Force B 푚푣2 푒푣퐵 = 휌

i B FF 푚푣 푝 I 퐵휌 = = I 푒 푒 Magnetic rigidity is the required magnetic bending strength for given radius and energy

Let’s see if you can tell me which INTRODUCTION direction these magnets bend the beam? beam 푩 푭 푩 i i i 푭

SMP - Introduction to Accelerators | fgg 42 Quadrupole magnets

. In a quadrupole magnet, the force increases linearly with displacement 퐹푥 = −푔푥 Consider a positive particle 퐹푦 = 푔푦 traveling into the page

N . The force on a particle on the right side S of the magnet is to the left . The force on a particle on the left side of

퐹 the magnet is to the right INTRODUCTION N S This magnet is horizontally focusing A distribution of particle would be focused on the x- plane and defocused on the y-plane

SMP - Introduction to Accelerators | fgg 43 Other n-pole magnets

N=1 Dipole N=2 Quadrupole N=3 Sextupole N=4 Octupole

1800 between poles 900 between poles 600 between poles 450 between poles General rule: poles are 3600/2n apart

Bending particles Focus particles Chromaticity High-order INTRODUCTION compensation corrections…

SMP - Introduction to Accelerators | fgg 44 Alternating gradient focusing

. Alternate H/V focusing magnets

. The accelerator is composed of a periodic repetition of FODO cells

QF QD QF QD QF QD QF QD

INTRODUCTION . The ideal particle will follow a particular trajectory, which closes on itself after one revolution . The real particles will perform oscillations around the ideal orbit

SMP - Introduction to Accelerators | fgg 45 Particle accelerators

Modern Physics Computing Quantum Physics Accelerator design code Particle Physics High performance computing

Engineering Radio Frequency Classical Physics Alignment & Survey Ultra high vacuum Mechanics Particle Electronics Electrodynamics Accelerator Magnet Technology Mechanical Cryogenics

SMP - Introduction to Accelerators | fgg 46 What is an RF system?

.Radio-Frequency in a particle accelerator is a system intended to transfer energy to a beam of charged particles by

interaction with an electric field oscillating at RF frequency

HV power Radio-Frequency High power amplifier building blocks Low Level RF

Transmission line - power amplifier INTRODUCTION Accelerating - high voltage power Cavity - accelerating cavity - low level RF system vacuum water cooling - auxiliary equipment system

SMP - Introduction to Accelerators | fgg 47 What is an RF system? (2)

.HV Power is an essential part for the RF system Many components such as HV . transformer, capacitor bank,

called “Modulator” INTRODUCTION

FNAL 200MHZ Linac Modulator

SMP - Introduction to Accelerators | fgg 48 What is an RF system? (3)

.High Power Amplifier device that provides the RF power: RF tube

(tetrode or triode) or a klystron

INTRODUCTION

FNAL/Linac 800 MHz FNAL/Linac 200 MHz 5 MW Triode Power 7MW Klystron RF system Amplifier SMP - Introduction to Accelerators | fgg 49 INTRODUCTION What is an RFsystem? (4) is an What

SMP FNAL/Linac 200 MHz coax line FNAL/Linaccoax 200MHz - .

Introductionto Accelerators | fgg minimumloss. reflectionand cavity withno transported from the amplifier tothe Transmission line

(

RF RF power is ≅

40ft long)

50

INTRODUCTION What is an RFsystem? (5) is an What

FNAL BoosterFNAL cavity

SMP - of gaps withof gaps aminimumpower loss .

Introductionto Accelerators | fgg accumulates electric energy in a energy ina series accumulates electric Accelerating cavity Accelerating

crèmede lacrème FNAL Linac side

- couple cavity

51

Fermilab Accelerator Chain

SMP - Introduction to Accelerators | fgg 52 Fermilab accelerator chain (until 2011)

Machine Energies Injector Cockcroft- 750 keV Walton Linac DTL + SCC 400 MeV Booster Synchrotron 8 GeV Main Injector Synchrotron 120 GeV Recycler Synchotron 8 GeV Electron Cooling Pelletron Pbar rings Synchrotron 8 GeV Tevatron Synchotron 1 TeV

SMP - Introduction to Accelerators | fgg 53 Fermilab accelerator chain (after 2012)

Machine Energy Injector RFQ 750 keV

Linac DTL + SCC 400 MeV 0.99c Booster Synchrotron 8 GeV

0.71c Main Injector Synchrotron 120 GeV Recycler Synchotron 8 GeV 0.04c Muon Campus Synchrotron 8 GeV

SMP - Introduction to Accelerators | fgg 54 Ion Source All starts with a simple bottle of hydrogen gas …

. The H2 gas is fed precisely into the volume between the electrodes

. a parallel magnetic field is applied to the cathode surface ION SOURCE ION

. an arc is applied between the electrodes – . e- in the arc efficiently ionize the gas to form a plasma of H+/e- . These ions strike the cathode and capture electrons which are repealed from the

cathode 퐶푠+ ions on metal increase yield H2 gas of sputtered negative ions

ANODE B

CESIUM CATHODE 퐵 ACCELERATOR ACCELERATOR CHAIN

EXTRACTOR electrons H- SMP - Introduction to Accelerators | fgg 55

Pre-Accelerator (1968-2012)

Jim and Ray (late 60’s)

ACCELERATOR

-

PRE

– ACCELERATOR ACCELERATOR CHAIN Jim and Ray (2010) SMP - Introduction to Accelerators | fgg 56 RFQ Injector Line (2012-present)

. RFQ is a relatively new type of linear

accelerator for very low velocity region

RIL . With the vanes provide the unique function of

– both focusing and accelerating in a remarkably compact structure . Beam is accelerated by longitudinal fields and focused by RF electric quadrupole fields

determined by geometry of the structure ACCELERATOR ACCELERATOR CHAIN

SMP - Introduction to Accelerators | fgg 57

Linac (1970-present)

LNAC

– 200MHz PA Low Energy tunnel

Linac Length (m) 200 m

Pulse Frequency 15 Hz ACCELERATOR ACCELERATOR CHAIN Kinetic Energy 0.750 400 MeV Frequency 201/804 MHz

Current 33ma High Energy tunnel High Energy Linac Gallery o N of Cavities 5 DTLs, 7 SCC SMP - Introduction to Accelerators | fgg 58 Booster (1970-present) Injection Energy : 400 MeV Beam throughput Extraction Energy: 8 GeV ퟕ. ퟓ푯풛 ퟏퟓ푯풛 ~0.3 miles circumference (now future)

Protons to Booster Neutrino ~4.5푥1012 ppp Experiment (BNB) BOOSTER 17 17 ~1.1푥10 2.210 pph

– MiniBooNE, SciBooNE, MicroBooNE Protons to support 120 GeV Beam Power = energy/time program 44 kW ~90 kW Protons to support Muon

Campus program (later) ACCELERATOR ACCELERATOR CHAIN

SMP - Introduction to Accelerators | fgg 59

8 GeV Program – BNB & Muon Campus

MiniBooNE SciBooNE MicroBooNE Muon Experiment Experiment Experiment Campus (2000-2012) (2007-2009) (start ~ 2015) Experiments v –oscillations Short-baseline (start ~ 2016) dedicated 흈흊 Single detector measurements g-2 experiment to check v-oscillations

ACCELERATOR ACCELERATOR EXPERIMENTS LSND result Mu2eexperiment

SMP - Introduction to Accelerators | fgg 60 Main Injector (1996-present)

Injection Energy : 8 GeV Beam throughput Ext. Energy: 120 GeV ramp 2.2sec 1.7 sec ~ 2 miles circunference (now future) Successful supported 12 푏푎푡푐ℎ푒푠 표푓 ~4.5푥1012 ppp 푝 production 푝 transfer into Recycler

MAIN INJECTOR MAIN storage Beam Power = – Provide 푝/푝 for energy/time Tevatron 400 kW ~700 kW Multi-batch “2+9” Operation Scheme Continue support $19 $19 $1D $14 $14 푝 for Test beam area 푝 for 120 GeV Neutrino program - MINOS, NOvA,

- LBNE (future) ACCELERATOR ACCELERATOR CHAIN

SMP - Introduction to Accelerators | fgg 61

120 GeV – Long Baseline n experiment

Minos Minerva NOvA LBNE Experiment Experiment Experiment Experiment (2006-present) (2009-present) (2014-200?) (start ~ 2025)

v physics dedicated 흈흊 v physics v physics measurements requires higher

ACCELERATOR ACCELERATOR EXPERIMENTS Start pushing requires higher beam power for beam beam power than NOvA power than Minos ~1-2 MW ~400 kW ~700 kW (Project X)

SMP - Introduction to Accelerators | fgg 62 ACCELERATOR CHAIN – Recycler/Electron Cooling Recycler

achieving higher beam power run in proton mode to assistMI in Current hasit been retrofitted to injection into the Stored Injector tunnel (above MI) Recycler resides inside the Main 2 milescircumference (1998 Recycler Energy: 8 GeV - antiprotons prior to present)

Tevatron & Electron & Electron Cooling

SMP -

Introductionto Accelerators | fgg

Electron Cooling Energy: 3.5 MeV Accumulator implemented in the cooling beyond that Provided additional easier to manipulate and accelerate Electron Cooling condensate the beam to make 25 - foot (2005) (2005 - high -

Pelletron

2011)

FNAL/

Pelletron 63

Pbar-rings 1986(1986 -2011)

Energy 8 GeV Beam parameters

~ 0.3 miles circumference pulse rate ~2 sec

RINGS

RINGS - - 120 GeV protons strike a 2 batches of

target to produce lots of 푝 ~ 4.5푥1012 ppp PBAR

PBAR In ~ 10 hrs. yield

– – ~ 1-2 푥1012 푝 !!

So, ~105 proton on target produced 2 푝

푝 target design evolved over the course of the years different materials were used Current being modified to

with the most common being be used as a proton machine

ACCELERATOR ACCELERATOR CHAIN ACCELERATOR ACCELERATOR CHAIN inconel (Ni,Cr,Fe) 600 for the Muon campus Typical lifetime: 4.14E19 pot program

SMP - Introduction to Accelerators | fgg 64

Tevatron (1983(1983)- 2011)

For 28 years the World’s Highest particle accelerator Energy 1 TeV 4 miles circumference

1983 Tevatron began operations as a 400 GeV to

TEVATRON

TEVATRON

– – provide fixed target machine 1984 reached 800 GeV

1986 Begin of collider era at Fermilab by accelerating protons and antiprotons and colliding them at two collision points

& experiments

Beam is accelerated by using 8 RF cavities which ACCELERATOR ACCELERATOR CHAIN ACCELERATOR ACCELERATOR CHAIN occupies ~ 0.3% of tunnel. The rest of the tunnel is lined with superconducting magnets and instrumentation.

SMP - Introduction to Accelerators | fgg 65 Tevatron (1983-2011)

Major engineering Major scientific contributions

achievements 1,000 PhD degrees Accelerators Discover:  First major superconducting Top quark and determined its mass to

synchrotron high precision TEVATRON First electron cooling system production mechanism for the top – developed for use with high-energy quark: pair and single production beam  퐵푐 meson and 퐵푠 oscillations Tevatron cryogenic system named Y(4140), quark structure International Historic Mechanical Observed: Engineer Landmark by ASMS in 1993  strongest evidence for violation of Tevatron antiproton source is the most matter-antimatter symmetry in intense source of antiprotons in the particles containing b-quark world and enabled the first p − 푝  Evidence for CP in neutral B mesons research in the TeV range Measured:

 bottom quark and properties ACCELERATOR ACCELERATOR CHAIN  Precise lifetimes of charm particles  Leading constraints on Higgs boson Fore more info about TeVatron history: http://www.fnal.gov/pub/tevatron/media.html  Most precise measurement of W boson mass SMP - Introduction to Accelerators | fgg 66

Protons demand going forward

ACCELERATOR ACCELERATOR CHAIN

SMP - Introduction to Accelerators | fgg 67 Beam diagnostic . Beam diagnostic instruments are essential for monitoring and assessing beam quality Diagnostic devices and quantity measured Measured Instrument Physical Effect Effect on beam Quantity Current Magnetic field Intensity Non-destructive transformer Beam position Electric/Magnet Position Non-destructive

ACCELERATOR ACCELERATOR CHAIN monitor field Wire Scanner Secondary Transverse Slightly particle creation size/shape destructive Beam loss Ionization Intensity Non-destructive Monitor SMP - Introduction to Accelerators | fgg 68 Beam diagnostic (1) Toroid Intensity devices used to measure a

pulse beam current Beam Position Monitor BPM Measure the center of the mass of the beam

Wire Scanner A thin wire is quickly moved across ACCELERATOR ACCELERATOR CHAIN the beam Multi Wire A vacuum chamber houses a paddle with wires which are kept under tension and high voltage

SMP - Introduction to Accelerators | fgg 69 Running the machines .Monitoring and Control . Main Control Room (MCR) staffed 24/7/365 . > 200k devices monitored/controlled through Accelerator Control Network (ACNET) . Respond and resolve alarms . minor and major . Tuning accelerators/beamlines for efficiency . Route/provide beam to desired/scheduled experiment/studies

ACCELERATOR ACCELERATOR CHAIN . Record events in electronic log book

SMP - Introduction to Accelerators | fgg 70 Running the machines (1) . Access Control . turn off and on each accelerator &

beamline for enclosure access . Provide a single point LOTO in most cases . Issue enclosure access keys . search and secure enclosures in preparation to

resume beam when needed ACCELERATOR ACCELERATOR CHAIN

SMP - Introduction to Accelerators | fgg 71 Running the machines (2) . First responders . fire alarm & ODH alarms

. equipment failure . Troubleshooting . system and component . expert contact when needed . Daily Schedule . maintain beam delivery

. adjust on the fly ACCELERATOR ACCELERATOR CHAIN

SMP - Introduction to Accelerators | fgg 72 A taste of what looks like to be in the

Main Control Room

ACCELERATOR ACCELERATOR CHAIN

SMP - Introduction to Accelerators | fgg 73 Radiation at a glance

.Radiation is energy that is transmitted in the form of waves

of stream of particles. It is present everywhere!!

Ionizing comes from both natural and man-made Radiation Non-ionizing lower radiation such as radio waves,

microwaves Alpha Beta

g--rays ACCELERATOR ACCELERATOR CHAIN

aluminum lead enclosures Beam

Can you give me an example of something you know that is radioactive?

SMP - Introduction to Accelerators | fgg 74 Application of accelerators

Three main applications: 1) Scientific research 2) Medical applications 3) Industrial uses CATEGORY OF ACCELERATORS # IN USE Nuclear/High-Energy Accelerators 120 Synchrotron radiation sources 100 Medical radioisotope production 1,000 Radiation therapy 5,000 Research accelerators (non-nuclear research) 1,000 Industrial processing and research 1,500

APPLICATION OF ACCELERATORS ACCELERATORS OF APPLICATION Ion implanters 7,000 TOTAL > 15,000

Data collected by W. Scarf & W. Wiesczycka (U.Amaldi Europhysics News, June 2000)

SMP - Introduction to Accelerators | fgg 75 Application of accelerators (2)

. Irradiation pasteurization is the process used on food irradiation . Food irradiation is the process of using ionizing radiation to kill harmful micro-organisms to reduce food spoilage and mildew development 푒− beam generator (10 MeV) 훾 60 Radiant energy -rays 퐶표 US labeling X-rays (max 5 MeV)

for irradiated foods APPLICATION OF ACCELERATORS ACCELERATORS OF APPLICATION Lower dose Higher dose

SMP - Introduction to Accelerators | fgg 76 Application of accelerators (3)

. Medical therapy

electron linacs for conventional radiation therapy

Low-energy hadron therapy (66 MeV) Neutron therapy (NTF)/FNAL

Injector linac

Medium-energy cyclotrons APPLICATION OF ACCELERATORS ACCELERATORS OF APPLICATION and synchrotrons for Quadrupole magnets hadron therapy with CNAO protons (250MeV) RF cavity Dipole magnets SMP - Introduction to Accelerators | fgg 77 Application of accelerators (4)

.Accelerator Driven System (ADS) . proton accelerator at low energy & high beam power . aim these protons to a heavy metal target and create lots of neutrons . These neutrons can drive the reaction in the reactor Picture taken from wikipedia . Continue to drive the reactor,

. Twofold application: generate energy APPLICATION OF ACCELERATORS ACCELERATORS OF APPLICATION & nuclear waste transmutation

SMP - Introduction to Accelerators | fgg 78 Superconducting RF R&D

. Fermilab is the lead on SRF R&D Program

. Fermilab has been developing the infrastructure and skill set to be a key player in superconducting RF technology applications . NML facility – propose site for ASTA (Advanced Superconducting Test Accelerator) . SRF technology is a highly efficient way to accelerate beams of particles . Several strings, or cavities are nestle in a vessel called a cryomodule, which bathes them in liquid helium and keeps them at the ACCELERATOR ACCELERATOR TECHNOLOGY ultra cold temperature . Future accelerators design involves SRF accelerator elements

SMP - Introduction to Accelerators | fgg 79 Future Accelerators . PIP-II (former Project-X), a high-power proton facility

Provide MW beam power to n experiments &

simultaneously multi-GeV beam for other experiments FUTURE FUTURE ACCELERATOR

SMP - Introduction to Accelerators | fgg 80 Future Accelerators (2) . International Linear Collider (ILC) Site: Japan Energy: 1TeV cm Technology: Superconduct Linac . Compact Linear Collider (CLIC) Site : Europe Energy: 3 TeV Technology; standard accelerator technology

FUTURE FUTURE ACCELERATOR . Plasma Accelerator SLAC has been building Facilities to demonstrate plasma accelerators

SMP - Introduction to Accelerators | fgg 81 Summary

Sometimes pretty crazy ideas are surprisingly good ones to make the world a better place Particles accelerators are not only used for research cancer treatment killing bacteria in food nuclear transmutation (and so many other applications that were not covered here…) Wherever life takes you, find something you think is important Do it because you are passionate about it, that you believe is worthwhile Challenge yourself Believe in yourself & Dig Deep! SMP - Introduction to Accelerators | fgg 82 Books, Webs and Lectures

1) USPAS Accelerator Schools [http://uspas.fnal.gov/] 2) Previous SMP accelerator lectures (thanks for sharing the material) 3) Connexions web site [http://cnx.org] 4) [http://cas.webhttp://www.clab.edc.uoc.gr/materials/pc/surf/ACCELERATORS_INTRO.HTML] 5) Food irradiation [http://www.epa.gov/radiation/sources/food_irrad.html] 6) CERN Accelerator Schools.cern.ch/cas 7) RF Linear Accelerators, 2nd edition, Thomas P. Wrangler, Wiley-VCH 8) Enertial of Modern Physics, T.R. Sandin, Addison-Wesley 9) … and I would like to thank many other outstanding references available online which helped formulate this lecture

SMP - Introduction to Accelerators | fgg 83