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Fermilab Public LectureFermilab Public Lecture
The Intensity FrontierThe Next Challenge for
Fermilab Stanley Wojcicki
Stanford University March 23, 2012
The Intensity FrontierThe Next Challenge for
Fermilab Stanley Wojcicki
Stanford University March 23, 2012
22Fermilab Public LectureFermilab Public Lecture
Our world is DIVERSEOur world is DIVERSE
Our goal is SIMPLIFICATIONOur goal is SIMPLIFICATION
All of Physics on a T-shirt (Leon L.)
All of Physics on a T-shirt (Leon L.)
For both Constituents and the Forces
For both Constituents and the Forces
very smallvery smallvery largevery large
33Fermilab Public LectureFermilab Public Lecture
Truth is ever to be found in simplicity, and not in the multiplicity and confusion of things. He is the God of order and not of confusion.
Sir Isaac Newton
Truth is ever to be found in simplicity, and not in the multiplicity and confusion of things. He is the God of order and not of confusion.
Sir Isaac Newton
44Fermilab Public LectureFermilab Public Lecture
THE GRAND QUESTIONSTHE GRAND QUESTIONS
What is the world made of ?What is the world made of ?
What holds it together ?What holds it together ?
Where do we come from?Where do we come from?
Why are we “us” and not “anti-us”?
Why are we “us” and not “anti-us”?
55Fermilab Public LectureFermilab Public Lecture
THE FUNDAMENTAL CONSTITUENTS THE FUNDAMENTAL CONSTITUENTS In 1920 there were 3 elementary
particles:proton (p+), electron (e-), photon (γ)
In 1920 there were 3 elementary particles:
proton (p+), electron (e-), photon (γ)In 1955 there were about 20 (+ their
antiparticles):p, e, γ and also: n, μ, ν, π, Κ, τ, θ, χ, Λ, Σ,
Ξ ...
In 1955 there were about 20 (+ their antiparticles):
p, e, γ and also: n, μ, ν, π, Κ, τ, θ, χ, Λ, Σ, Ξ ...
And starting in the 1960’s there was even a greater explosion
And starting in the 1960’s there was even a greater explosion
CAN SO MANY PARTICLES BE ALL ELEMENTARY?CAN SO MANY PARTICLES BE ALL ELEMENTARY?
66Fermilab Public LectureFermilab Public Lecture
If I could remember the names of all these particles, I’d be a
botanist. Enrico
Fermi
If I could remember the names of all these particles, I’d be a
botanist. Enrico
Fermi
77Fermilab Public LectureFermilab Public Lecture
THE FUNDAMENTAL CONSTITUENTSWHAT WE BELIEVE TODAY
THE FUNDAMENTAL CONSTITUENTSWHAT WE BELIEVE TODAY
1) Quarks and Leptons are fundamental
2)They may be point particles or little strings3) There are at least 6 of
each, maybe more
1) Quarks and Leptons are fundamental
2)They may be point particles or little strings3) There are at least 6 of
each, maybe more
88Fermilab Public LectureFermilab Public Lecture
I have long held an opinion, amounting almost to conviction,
in common, I believe, with many other lovers of natural knowledge, that the various
forms under which the forces of matter are made manifest have
one common origin. Michael
Faraday
I have long held an opinion, amounting almost to conviction,
in common, I believe, with many other lovers of natural knowledge, that the various
forms under which the forces of matter are made manifest have
one common origin. Michael
Faraday
99Fermilab Public LectureFermilab Public Lecture
THE FIRST UNIFICATION THE FIRST UNIFICATION Isaac Newton (1642 -
1727)Isaac Newton (1642 -
1727)
Celestial GravityCelestial Gravity Terrestial GravityTerrestial Gravity
They are the same They are the same
1010
Fermilab Public LectureFermilab Public Lecture
THE SECOND UNIFICATION THE SECOND UNIFICATION James Clark Maxwell (1831 -
1879)James Clark Maxwell (1831 -
1879)
Electricity and magnetismare different
manifestations of the same phenomenon
Electricity and magnetismare different
manifestations of the same phenomenon
==
1111
Fermilab Public LectureFermilab Public Lecture
THE THIRD UNIFICATION THE THIRD UNIFICATION S. Glashow, A. Salam, S. Weinberg
(1967-68)S. Glashow, A. Salam, S. Weinberg
(1967-68)
Holds atoms together;
Responsible for electricity, magnetism
Holds atoms together;
Responsible for electricity, magnetism
Responsible for neutron decay, radioactivity in
reactors
Responsible for neutron decay, radioactivity in
reactors
Weak + Electromagnetic → Electroweak
Weak + Electromagnetic → Electroweak
1212
Fermilab Public LectureFermilab Public Lecture
The Grand Unified Theory (GUT) ?The String Theory ?
The Grand Unified Theory (GUT) ?The String Theory ?
THE NEXT UNIFICATION (S) ?THE NEXT UNIFICATION (S) ?
1313
Fermilab Public LectureFermilab Public Lecture
THE FAMILIAR FORCESTHE FAMILIAR FORCES
But there are also forces at a distance
Examples: Gravity, Magnetism
But there are also forces at a distance
Examples: Gravity, Magnetism
Pull (contact)Pull (contact)Push (contact)Push (contact)
1414
Fermilab Public LectureFermilab Public Lecture
THE FORCES IN PARTICLE PHYSICS THE FORCES IN PARTICLE PHYSICS
How do we describe them?How do we describe them?
Exchange ForcesExchanged particle can be heavy
It is virtual
Uncertainty Principle:ΔEΔt ≳ ħ
Exchange ForcesExchanged particle can be heavy
It is virtual
Uncertainty Principle:ΔEΔt ≳ ħ
Exchange Force (repulsive)Exchange Force (repulsive)
The Standard ModelThe Standard Model
1515
Fermilab Public LectureFermilab Public Lecture
THE STEPS TOWARDS KNOWLEDGETHE STEPS TOWARDS KNOWLEDGE
Example: Chemical Elements Example: Chemical Elements
1. Observation (New Data):1. Observation (New Data):Hydrogen, Carbon, Copper, Mercury,
Gold...Hydrogen, Carbon, Copper, Mercury,
Gold...
3. Understanding (Why?):3. Understanding (Why?):Quantum Mechanics,
Spin...Quantum Mechanics,
Spin...
2. Classification:2. Classification:Periodic TablePeriodic Table
1616
Fermilab Public LectureFermilab Public Lecture
WHERE ARE WE IN PARTICLE PHYSICS?WHERE ARE WE IN PARTICLE PHYSICS?
1. Observation : 1. Observation : Many Particles,
SimilaritiesMany Particles,
Similarities Structure in the Proton Structure in the Proton
2. Classification:
2. Classification:Quarks, Leptons,Quarks, Leptons,
Force CarriersForce Carriers⟶ SM⟶ SM
3. Understanding:3. Understanding:Many Questions Need AnswersMany Questions Need Answers
1717
Fermilab Public LectureFermilab Public Lecture
FEW DETAILED QUESTIONSFEW DETAILED QUESTIONS
Why 3 families of quarks and leptons?Do all forces become one?
Why are the masses of quarks so different?Why are neutrino masses so small?
What happened to anti-matter?How will Standard Model break down?
What is dark matter?What is dark energy?
Are quarks and leptons little strings?
Why 3 families of quarks and leptons?Do all forces become one?
Why are the masses of quarks so different?Why are neutrino masses so small?
What happened to anti-matter?How will Standard Model break down?
What is dark matter?What is dark energy?
Are quarks and leptons little strings?
1818
Fermilab Public LectureFermilab Public Lecture
A theory is more impressive the greater the simplicity of
its premises, the more diverse the things it relates, and the more extended its
area of applicability. Albert Einstein
A theory is more impressive the greater the simplicity of
its premises, the more diverse the things it relates, and the more extended its
area of applicability. Albert Einstein
1919
Fermilab Public LectureFermilab Public Lecture
Colliders, Tevatron ➙ LHCColliders, Tevatron ➙ LHC
External beamfixed target
External beamfixed target
TelescopesSatellitesBalloons
Large Arrays
TelescopesSatellitesBalloons
Large Arrays
THE 3 FRONTIERS OF PARTICLE PHYSICSTHE 3 FRONTIERS OF PARTICLE PHYSICS
Intensity Frontier experiments can be sensitive to mass scales >> LHC
Intensity Frontier experiments can be sensitive to mass scales >> LHC
2020
Fermilab Public LectureFermilab Public Lecture
ENERGY AND INTENSITY FRONTIERSENERGY AND INTENSITY FRONTIERSDirect and Indirect MeasurementsDirect and Indirect Measurements
Real particles created from energy
Requires high energy
Real particles created from energy
Requires high energy
Virtual particles existfor a short time
Requires high intensity
Virtual particles existfor a short time
Requires high intensity
E = mc2
E = mc2
Albert EinsteinAlbert Einstein
ΔE Δt ≥ ħΔE Δt ≥ ħ
Werner HeisenbergWerner Heisenberg
2121
Fermilab Public LectureFermilab Public Lecture
FROM 300 Kw TO 2.2 MwFROM 300 Kw TO 2.2 Mw
1. Upgrade of an existing fixed target complex from 300 Kw to 700 Kw
1. Upgrade of an existing fixed target complex from 300 Kw to 700 Kw
2. Construction of a new accelerator complex - Project X
2. Construction of a new accelerator complex - Project X
Number of Protons
Time
Number of Protons
Time
>2MW @ 120 GeV
3 MW @ 3 GeV
150 kW @ 8 GeV
2222
Fermilab Public LectureFermilab Public Lecture
PROPOSED LOCATION OF PROJECT XPROPOSED LOCATION OF PROJECT X
2323
Fermilab Public LectureFermilab Public Lecture
PROJECT X EXPERIMENTAL CAMPUSPROJECT X EXPERIMENTAL CAMPUS
2424
Fermilab Public LectureFermilab Public Lecture
FEYNMAN DIAGRAMS FEYNMAN DIAGRAMS
Method for Calculating Particle Properties and the Rates for
Their Interactions and Decays
Method for Calculating Particle Properties and the Rates for
Their Interactions and Decays
Rules are Simpler than in Monopoly:
Rules are Simpler than in Monopoly:
1. Each diagram is composed of vertices, internal lines, external lines
1. Each diagram is composed of vertices, internal lines, external lines
3. Add up all the diagrams and square the sum3. Add up all the diagrams and square the sum
2. Each of these contributes a factor to the amplitude for this diagram
2. Each of these contributes a factor to the amplitude for this diagram
Allows Visualization of the ProcessAllows Visualization of the Process
2525
Fermilab Public LectureFermilab Public Lecture
AN EXAMPLE (Feynman and Indirect Expt)
AN EXAMPLE (Feynman and Indirect Expt)
A decay K0→ μ+μ- A decay K0→ μ+μ-
But the prediction for this rate based on this diagram did not
agree with the experiment
But the prediction for this rate based on this diagram did not
agree with the experiment
Few years later, required quark, charm, was discovered
Few years later, required quark, charm, was discovered
The “box” diagram on the right describes a mechanism for this
decay
The “box” diagram on the right describes a mechanism for this
decayνν
Theory and experiment could be reconciled if one postulated
additional diagram with a new quark
Theory and experiment could be reconciled if one postulated
additional diagram with a new quark
νν
2626
Fermilab Public LectureFermilab Public Lecture
ANOTHER EXAMPLE - FROM ASTRONOMY ANOTHER EXAMPLE - FROM ASTRONOMY
In 1781 William Herschel discovered the 7th planet, eventually named Uranus, using the 15cm telescope
he had constructed himself.
In 1781 William Herschel discovered the 7th planet, eventually named Uranus, using the 15cm telescope
he had constructed himself.NEW YORK
LIBRARYNEW YORK
LIBRARY
But there was a problem: Uranus trajectory in the sky did not follow the expectation from
Newton’s law
But there was a problem: Uranus trajectory in the sky did not follow the expectation from
Newton’s lawTwo possible explanations were put
forward:a) Newton’s law was not rigorously trueb) There was another perturbing planet
Two possible explanations were put forward:
a) Newton’s law was not rigorously trueb) There was another perturbing planet
2727
Fermilab Public LectureFermilab Public Lecture
Urbain LeVerrier (France) and John Adams (UK) espoused the planet idea and calculated its
location.
Urbain LeVerrier (France) and John Adams (UK) espoused the planet idea and calculated its
location.LeVerrier asked Johann Galle at the Berlin
Observtory to look for a planet in the suggested sky area.
LeVerrier asked Johann Galle at the Berlin Observtory to look for a planet in the suggested
sky area. In 1846 Galle found the planet
(named Neptune)within 1o of LeVerrier ‘s prediction. LeVerrier got credit for
the discovery.
In 1846 Galle found the planet (named Neptune)within 1o of LeVerrier ‘s prediction. LeVerrier got credit for
the discovery.
NEWTON WAS RIGHT AFTER ALLNEWTON WAS RIGHT AFTER ALL
2828
Fermilab Public LectureFermilab Public Lecture
DIFFERENT MEASUREMENTSDIFFERENT MEASUREMENTSprecision measurements
orrare (forbidden)
processes
precision measurementsor
rare (forbidden) processes
interactions or decaysor
particle properties
interactions or decaysor
particle properties
K0→π0νν μ g-2
μ→e captureelectric dipole
moments
particle properties particle properties interactions,interactions,decaysdecays
precision measurements
precision measurements
rare (forbidden) processes
rare (forbidden) processes
+ NEUTRINO INTERACTONS+ NEUTRINO INTERACTONS
2929
Fermilab Public LectureFermilab Public Lecture
Question: What are spin and magnetic moment?
Question: What are spin and magnetic moment?
Answer: Fundamental properties of particles, like mass or charge
Answer: Fundamental properties of particles, like mass or charge
Ratio of spin and magnetic moment is called g factor
Ratio of spin and magnetic moment is called g factor
For charged leptons (e,μ,τ), g is close to 2 and its deviation from 2 (g-2) can be both
measured and calculated very precisely (<1 ppm)
For charged leptons (e,μ,τ), g is close to 2 and its deviation from 2 (g-2) can be both
measured and calculated very precisely (<1 ppm)
gμexp = 2.00233184178(128)gμexp = 2.00233184178(128)
Classical analogue: spinning top that is
charged
Classical analogue: spinning top that is
charged
3030
Fermilab Public LectureFermilab Public Lecture
MUON g-2 (THEORY)MUON g-2 (THEORY)Muon g-2 can be calculated very preciselyThus disagreement between theory and
experiment might be an indication of new physics
Muon g-2 can be calculated very preciselyThus disagreement between theory and
experiment might be an indication of new physics
Leading diagramLeading diagram
Higher order diagramsHigher order diagrams
Possible diagram from new physics (supersymmetry)
Possible diagram from new physics (supersymmetry)
3131
Fermilab Public LectureFermilab Public Lecture
MUON g-2 (EXPERIMENT)MUON g-2 (EXPERIMENT)Protons on target → pions→π➟μν →store μ in
ringProtons on target → pions→π➟μν →store μ in
ringObserve muon spin rotation
through muon decays to electrons
Observe muon spin rotation through muon decays to
electrons
Frequency(f) = no. of cycles/timeFrequency(f) = no. of cycles/time
g-2 α f/Bg-2 α f/B“Never measure
anything but frequency”
I.I.Rabi
“Never measure anything but frequency”
I.I.Rabi
BNL experimentBNL experiment
Need lots of muons Need lots of muons
3232
Fermilab Public LectureFermilab Public Lecture
MUON CAPTURE (mu2e)MUON CAPTURE (mu2e)What happens when μ- stops in matter?What happens when μ- stops in matter?
Can it transform itself into an electron?Can it transform itself into an electron?
Yes, but VERY rarely. In SM, ∼10-52
Yes, but VERY rarely. In SM, ∼10-52
Only SM diagram possibleOnly SM diagram possible
Excellent candidate for looking for New Physics
Excellent candidate for looking for New Physics
Current experimental limit: ∼10-12
Can one do significantly better than that? Current experimental limit: ∼10-12
Can one do significantly better than that?
a) It can decay: μ- →e-ννb) It can be captured by the nucleus: μ- +p→n+ν
a) It can decay: μ- →e-ννb) It can be captured by the nucleus: μ- +p→n+ν
3333
Fermilab Public LectureFermilab Public Lecture
Most New Physics models predict a rate for muon conversion to electrons of ∼10-16
- 10-13
Most New Physics models predict a rate for muon conversion to electrons of ∼10-16
- 10-13
To reach 10-16 need a lot of muons, ∼1019 To reach 10-16 need a lot of muons, ∼1019
This requires LOT of protons and sophisticated apparatusThis requires LOT of protons and sophisticated apparatus
Compare to about 5 x 1019
(?)grains of sand on all the
world’s beaches
Compare to about 5 x 1019
(?)grains of sand on all the
world’s beaches
3434
Fermilab Public LectureFermilab Public Lecture
DECAY MODE: K0→πo ν ν DECAY MODE: K0→πo ν ν
The New Physics can increase this decay rate
The New Physics can increase this decay rate
Very difficult experimentally; not seen yet
Very difficult experimentally; not seen yet
neutral → neutral + neutral + neutral
neutral → neutral + neutral + neutral
Hence no visible tracksHence no visible tracksTo achieve required precision need high
intensityTo achieve required precision need high
intensity
Standard Model prediction:
Standard Model prediction: BR∼.2 x 10-10BR∼.2 x 10-10
There are today about 7 x 109 people in the world
There are today about 7 x 109 people in the world
3535
Fermilab Public LectureFermilab Public Lecture
Need to make small Ko beam to have good direction precision
Need to make small Ko beam to have good direction precision
Also good photon detection and measurement
Also good photon detection and measurement
Strive for 10% measurement of
BR
Strive for 10% measurement of
BR
All of this requires high intensityAll of this requires high intensity
3636
Fermilab Public LectureFermilab Public Lecture
NEUTRINOSNEUTRINOS
They are produced in nature:
They are produced in nature:
in the sun, in cosmic rays, in the earth, in the oceans,...take 99% of energy in supernovas
in the sun, in cosmic rays, in the earth, in the oceans,...take 99% of energy in supernovas
They are also produced by humans:
They are also produced by humans: in reactors, by the accelerators, in medical
isotopesin reactors, by the accelerators, in medical
isotopesThey are unique and important but ill
understoodThey may be responsible for our existence
WE MUST STUDY THEM
They are unique and important but ill understood
They may be responsible for our existenceWE MUST STUDY THEM
They are fundamental and ubiquitousThey are fundamental and ubiquitous1014 go through each one of us
every sec1014 go through each one of us
every sec
3737
Fermilab Public LectureFermilab Public Lecture
NEUTRINOS ARE WEIRD
NEUTRINOS ARE WEIRD
They hardly interact with matter: Out of ∼100,000 all but one will get through 450
miles of earth (like a hot knife through butter)
They hardly interact with matter: Out of ∼100,000 all but one will get through 450
miles of earth (like a hot knife through butter)
Neutrino masses are tiny; their mass is no more than one millionth the mass of an
electron
Neutrino masses are tiny; their mass is no more than one millionth the mass of an
electron
As they move along they change from
As they move along they change fromone flavor to another,
eg. νμ→ ντ and back again
one flavor to another, eg. νμ→ ντ and back
again
3838
Fermilab Public LectureFermilab Public Lecture
NEUTRINO AND ELECTRON MASSES COMPARED
NEUTRINO AND ELECTRON MASSES COMPARED
electronelectronneutrinoneutrino
3939
Fermilab Public LectureFermilab Public Lecture
NEUTRINO EVENT RATESNEUTRINO EVENT RATES
Thus for precise measurement we need:
Thus for precise measurement we need:
large detector masslarge ν flux ie. intense proton
beam
large detector masslarge ν flux ie. intense proton
beam
No of events will be proportional to: x-section x detector mass x
flux x time
No of events will be proportional to: x-section x detector mass x
flux x time
⇒⇒ ⇒⇒protons target pions neutrinos detectorprotons target pions neutrinos detector
4040
Fermilab Public LectureFermilab Public Lecture
MINOS (Far Det.)
735 km
LBNE(Long Baseline Neutrino Experiment)
1300 km
NOvA810 km
MiniBooNEMINERvA
MicroBooNEShort Baseline Program
AERIAL VIEW OF POTENTIAL FERMILAB NEUTRINO PROGRAM
AERIAL VIEW OF POTENTIAL FERMILAB NEUTRINO PROGRAM
4141
Fermilab Public LectureFermilab Public Lecture
Principal Goals of future neutrino program:
a) Mass hierarchy: which ν is heaviestb) Study of matter-antimatter
symmetryc) Search for more ν’s, unexpected
Principal Goals of future neutrino program:
a) Mass hierarchy: which ν is heaviestb) Study of matter-antimatter
symmetryc) Search for more ν’s, unexpected
AN EXAMPLE: NOvA EXPERIMENTAN EXAMPLE: NOvA EXPERIMENT
14,700 tons, 810 km away, to start in 2013
14,700 tons, 810 km away, to start in 2013
385,000 extrusions385,000 extrusions
4242
Fermilab Public LectureFermilab Public Lecture
CONCLUDING REMARKSCONCLUDING REMARKS
Since its beginning, some 40 years ago, Fermilab has dominated the
high energy frontier in particle physics
Since its beginning, some 40 years ago, Fermilab has dominated the
high energy frontier in particle physics
This torch has now passed to CERN and LHC
This torch has now passed to CERN and LHC
The richness and diversity of currently planned program on the
intensity frontier should keep Fermilab at the forefront of particle physics for
many years to come
The richness and diversity of currently planned program on the
intensity frontier should keep Fermilab at the forefront of particle physics for
many years to come
4343
Fermilab Public LectureFermilab Public Lecture
ONE GLORIOUS ERA IS COMING TO AN END
ONE GLORIOUS ERA IS COMING TO AN END
4444
Fermilab Public LectureFermilab Public Lecture
ANOTHER ONE, EQUALLY PROMISING, IS JUST AROUND
THE CORNER
ANOTHER ONE, EQUALLY PROMISING, IS JUST AROUND
THE CORNER
THANK YOU FOR YOUR ATTENTIONTHANK YOU FOR YOUR ATTENTION
I want to acknowledge help and use of graphics from R.Bernstein, R.Tschirhart, S.Holmes and Y.K.Kim
I want to acknowledge help and use of graphics from R.Bernstein, R.Tschirhart, S.Holmes and Y.K.Kim