The Large Hadron Collider The Worlds Largest Microscope

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The Large Hadron Collider The Structure of Matter The Four Forces Final Picture The LHC Theory Issues The Large Hadron Collider - the World’s Largest Microscope Rahul Basu August 13, 2008

Transcript of The Large Hadron Collider The Worlds Largest Microscope

Page 1: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Large Hadron Collider- the World’s Largest Microscope

Rahul Basu

August 13, 2008

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

1 The Large Hadron ColliderNeed for a Collider

2 The Structure of MatterThe Fundamental Particles

3 The Four Forces

4 Final Picture

5 The LHCThe Collision ProcessSuperconducting Bending MagnetsThe Detectors

6 Theory Issues

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

The Large Hadron Collider

Large Hadron Collider⇓

An enormous particleaccelerator due to becomeoperational in August 2008that will collide beams ofprotons at an energy of 14TeV (and eventually leadnuclei of energy 1150TeV).

Figure: 27 km circumference ringTeV: Unit of energy used in particle physics ' 1.6 ergs – about theenergy of a flying mosquito – but squeezed into a space a billion (millionmillion) times smaller.

Page 4: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

The Large Hadron Collider

Large Hadron Collider⇓

An enormous particleaccelerator due to becomeoperational in August 2008that will collide beams ofprotons at an energy of 14TeV (and eventually leadnuclei of energy 1150TeV).

Figure: 27 km circumference ringTeV: Unit of energy used in particle physics ' 1.6 ergs – about theenergy of a flying mosquito – but squeezed into a space a billion (millionmillion) times smaller.

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

CERN – where the Web was born

CERN is the European Organization for Nuclear Research, the world’s largestparticle physics centre sitting astride the Franco-Swiss border near Geneva.CERN is a laboratory where scientists unite to study the building blocks ofmatter and the forces that hold them together. CERN exists primarily toprovide them with the necessary tools. These are accelerators, which accelerateparticles to almost the speed of light and detectors to make the particlesvisible. (It is also where the World Wide Web was born!)

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

LHC - machine and experiments

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

The Need for a Collider

But why do we need to build this collider. . .

LHC ⇒ a voyage of discovery that began in the late 19th century withthe discovery of radioactivity and subsequently, alpha, beta, gamma rays,X rays, and many new particles as the fundamental building blocks ofnature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )

Today we know what these particles are but along the way many newquestions have arisen which need to be answered (along the way, many ofthese discoveries have also given us TV’s, computers, medical imagingdevices, . . . )

The LHC is built to answer many of these new questions as we stand onthe threshold of this new century.

Page 8: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

The Need for a Collider

But why do we need to build this collider. . .

LHC ⇒ a voyage of discovery that began in the late 19th century withthe discovery of radioactivity and subsequently, alpha, beta, gamma rays,X rays, and many new particles as the fundamental building blocks ofnature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )

Today we know what these particles are but along the way many newquestions have arisen which need to be answered (along the way, many ofthese discoveries have also given us TV’s, computers, medical imagingdevices, . . . )

The LHC is built to answer many of these new questions as we stand onthe threshold of this new century.

Page 9: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

The Need for a Collider

But why do we need to build this collider. . .

LHC ⇒ a voyage of discovery that began in the late 19th century withthe discovery of radioactivity and subsequently, alpha, beta, gamma rays,X rays, and many new particles as the fundamental building blocks ofnature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )

Today we know what these particles are but along the way many newquestions have arisen which need to be answered (along the way, many ofthese discoveries have also given us TV’s, computers, medical imagingdevices, . . . )

The LHC is built to answer many of these new questions as we stand onthe threshold of this new century.

Page 10: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Need for a Collider

The Need for a Collider

But why do we need to build this collider. . .

LHC ⇒ a voyage of discovery that began in the late 19th century withthe discovery of radioactivity and subsequently, alpha, beta, gamma rays,X rays, and many new particles as the fundamental building blocks ofnature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )

Today we know what these particles are but along the way many newquestions have arisen which need to be answered (along the way, many ofthese discoveries have also given us TV’s, computers, medical imagingdevices, . . . )

The LHC is built to answer many of these new questions as we stand onthe threshold of this new century.

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

But why study the structure of Matter?

Universe is built up of buildingblocks (elementary particles)

All these particles existed in theshort time just after the BigBang but no longer. . .

Can only be created in highenergy particle collisions

Studying particle collisions ⇒looking back in time, recreating

the environment present at the

origin of our Universe.

What for – to understand the formation of stars, earth, trees, everything you

see around and, finally, us!

Page 12: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

But why study the structure of Matter?

Universe is built up of buildingblocks (elementary particles)

All these particles existed in theshort time just after the BigBang but no longer. . .

Can only be created in highenergy particle collisions

Studying particle collisions ⇒looking back in time, recreating

the environment present at the

origin of our Universe.

What for – to understand the formation of stars, earth, trees, everything you

see around and, finally, us!

Page 13: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

But why study the structure of Matter?

Universe is built up of buildingblocks (elementary particles)

All these particles existed in theshort time just after the BigBang but no longer. . .

Can only be created in highenergy particle collisions

Studying particle collisions ⇒looking back in time, recreating

the environment present at the

origin of our Universe.

What for – to understand the formation of stars, earth, trees, everything you

see around and, finally, us!

Page 14: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

But why study the structure of Matter?

Universe is built up of buildingblocks (elementary particles)

All these particles existed in theshort time just after the BigBang but no longer. . .

Can only be created in highenergy particle collisions

Studying particle collisions ⇒looking back in time, recreating

the environment present at the

origin of our Universe.

What for – to understand the formation of stars, earth, trees, everything you

see around and, finally, us!

Page 15: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

But why study the structure of Matter?

Universe is built up of buildingblocks (elementary particles)

All these particles existed in theshort time just after the BigBang but no longer. . .

Can only be created in highenergy particle collisions

Studying particle collisions ⇒looking back in time, recreating

the environment present at the

origin of our Universe.

What for – to understand the formation of stars, earth, trees, everything you

see around and, finally, us!

Page 16: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

But why study the structure of Matter?

Universe is built up of buildingblocks (elementary particles)

All these particles existed in theshort time just after the BigBang but no longer. . .

Can only be created in highenergy particle collisions

Studying particle collisions ⇒looking back in time, recreating

the environment present at the

origin of our Universe.

What for – to understand the formation of stars, earth, trees, everything you

see around and, finally, us!

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

Let’s start at the very beginning. . .

Everything in the Universe is built up of basic building blocks calledelementary particles

Matter⇒ atoms⇒ electrons and nucleus⇒ protons and neutrons⇒ quarks

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

The Structure of Matter

We have just met our very first elementary particles – the electron,and two types of quarks (u, d).

There is one more, a (almost) massless particle the neutrino ν. Itplays a vital role in reactions that convert neutrons to protons andvice versa. Such reactions allow matter to stay in the stable form weobserve and are also important in fuelling the Sun and the otherstars.

These four particles are all we need to build the ordinary matter wesee around us!!!

In fact, there are less “ordinary” forms of matter that exist which we can’t see:

cosmic matter coming from space, high energy matter that we create in our

laboratory and the “mirror image” of all of it, antimatter. To include them in

the picture, we need a more general description and more particles.

Page 19: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

The Structure of Matter

We have just met our very first elementary particles – the electron,and two types of quarks (u, d).

There is one more, a (almost) massless particle the neutrino ν. Itplays a vital role in reactions that convert neutrons to protons andvice versa. Such reactions allow matter to stay in the stable form weobserve and are also important in fuelling the Sun and the otherstars.

These four particles are all we need to build the ordinary matter wesee around us!!!

In fact, there are less “ordinary” forms of matter that exist which we can’t see:

cosmic matter coming from space, high energy matter that we create in our

laboratory and the “mirror image” of all of it, antimatter. To include them in

the picture, we need a more general description and more particles.

Page 20: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

The Structure of Matter

We have just met our very first elementary particles – the electron,and two types of quarks (u, d).

There is one more, a (almost) massless particle the neutrino ν. Itplays a vital role in reactions that convert neutrons to protons andvice versa. Such reactions allow matter to stay in the stable form weobserve and are also important in fuelling the Sun and the otherstars.

These four particles are all we need to build the ordinary matter wesee around us!!!

In fact, there are less “ordinary” forms of matter that exist which we can’t see:

cosmic matter coming from space, high energy matter that we create in our

laboratory and the “mirror image” of all of it, antimatter. To include them in

the picture, we need a more general description and more particles.

Page 21: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

The Structure of Matter

We have just met our very first elementary particles – the electron,and two types of quarks (u, d).

There is one more, a (almost) massless particle the neutrino ν. Itplays a vital role in reactions that convert neutrons to protons andvice versa. Such reactions allow matter to stay in the stable form weobserve and are also important in fuelling the Sun and the otherstars.

These four particles are all we need to build the ordinary matter wesee around us!!!

In fact, there are less “ordinary” forms of matter that exist which we can’t see:

cosmic matter coming from space, high energy matter that we create in our

laboratory and the “mirror image” of all of it, antimatter. To include them in

the picture, we need a more general description and more particles.

Page 22: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

The Structure of Matter

We have just met our very first elementary particles – the electron,and two types of quarks (u, d).

There is one more, a (almost) massless particle the neutrino ν. Itplays a vital role in reactions that convert neutrons to protons andvice versa. Such reactions allow matter to stay in the stable form weobserve and are also important in fuelling the Sun and the otherstars.

These four particles are all we need to build the ordinary matter wesee around us!!!

In fact, there are less “ordinary” forms of matter that exist which we can’t see:

cosmic matter coming from space, high energy matter that we create in our

laboratory and the “mirror image” of all of it, antimatter. To include them in

the picture, we need a more general description and more particles.

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

Structure of Matter

Observations of cosmic rays

and particle tracks in

accelerators have uncovered

many more particles – muon,

tau particle, their

corresponding neutrinos and

many heavy particles which

are not fundamental but

made up of heavy quarks.And finally there is anti-matter, the “mirror image” of ordinary matter

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

Anti-Matter

Matter and antimatter are perfect opposites; for each of the basicparticles of matter, there exists an antiparticle, in which properties suchas the electric charge are reversed.

When matter andantimatter meet, theyannihilate each other,creating energy (2mc2 - 1gm ∼ 107MJ ∼ 2kt TNT)which reappears asphotons or otherparticle-antiparticle pairs.

Puzzle: When the universe was formed - equal amounts of matter and

anti-matter (Baryon Symmetric Universe) today there is virtually none. . . need

a mechanism of baryon number violation

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

Anti-Matter

Matter and antimatter are perfect opposites; for each of the basicparticles of matter, there exists an antiparticle, in which properties suchas the electric charge are reversed.

When matter andantimatter meet, theyannihilate each other,creating energy (2mc2 - 1gm ∼ 107MJ ∼ 2kt TNT)which reappears asphotons or otherparticle-antiparticle pairs.

Puzzle: When the universe was formed - equal amounts of matter and

anti-matter (Baryon Symmetric Universe) today there is virtually none. . . need

a mechanism of baryon number violation

Page 26: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Fundamental Particles

Anti-Matter

Matter and antimatter are perfect opposites; for each of the basicparticles of matter, there exists an antiparticle, in which properties suchas the electric charge are reversed.

When matter andantimatter meet, theyannihilate each other,creating energy (2mc2 - 1gm ∼ 107MJ ∼ 2kt TNT)which reappears asphotons or otherparticle-antiparticle pairs.

Puzzle: When the universe was formed - equal amounts of matter and

anti-matter (Baryon Symmetric Universe) today there is virtually none. . . need

a mechanism of baryon number violation

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

Matter

Fundamental particles bind together to form structures on all scales.

Hadrons⇒ Baryons

Mesons⇒ qqq

qq̄

Protons and Neutrons (baryons – qqq) bind⇒ atoms and molecules⇒ liquids and solids⇒ huge conglomerations of matter in stars and galaxies.

They do this through forces

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The Four ForcesFinal Picture

The LHCTheory Issues

. . . and the four forces

Gravity(10−40) – the most familiar

Electromagnetic(10−2) – which manifests itself in the effects ofelectricity and magnetism.

Weak(10−7) – leads to the decay of neutrons (which underlies manynatural occurrences of radioactivity) and allows the conversion of aproton into a neutron (responsible for hydrogen burning in thecentre of stars).

Strong(1) – holds quarks together within protons, neutrons andother particles. It also prevents the protons in the nucleus fromflying apart under the influence of the repulsive electrical forcebetween them (they all have positive charge!).

Each of these has its own “carrier” particle!

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

. . . and the four forces

Gravity(10−40) – the most familiar

Electromagnetic(10−2) – which manifests itself in the effects ofelectricity and magnetism.

Weak(10−7) – leads to the decay of neutrons (which underlies manynatural occurrences of radioactivity) and allows the conversion of aproton into a neutron (responsible for hydrogen burning in thecentre of stars).

Strong(1) – holds quarks together within protons, neutrons andother particles. It also prevents the protons in the nucleus fromflying apart under the influence of the repulsive electrical forcebetween them (they all have positive charge!).

Each of these has its own “carrier” particle!

Page 30: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

. . . and the four forces

Gravity(10−40) – the most familiar

Electromagnetic(10−2) – which manifests itself in the effects ofelectricity and magnetism.

Weak(10−7) – leads to the decay of neutrons (which underlies manynatural occurrences of radioactivity) and allows the conversion of aproton into a neutron (responsible for hydrogen burning in thecentre of stars).

Strong(1) – holds quarks together within protons, neutrons andother particles. It also prevents the protons in the nucleus fromflying apart under the influence of the repulsive electrical forcebetween them (they all have positive charge!).

Each of these has its own “carrier” particle!

Page 31: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

. . . and the four forces

Gravity(10−40) – the most familiar

Electromagnetic(10−2) – which manifests itself in the effects ofelectricity and magnetism.

Weak(10−7) – leads to the decay of neutrons (which underlies manynatural occurrences of radioactivity) and allows the conversion of aproton into a neutron (responsible for hydrogen burning in thecentre of stars).

Strong(1) – holds quarks together within protons, neutrons andother particles. It also prevents the protons in the nucleus fromflying apart under the influence of the repulsive electrical forcebetween them (they all have positive charge!).

Each of these has its own “carrier” particle!

Page 32: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

. . . and the four forces

Gravity(10−40) – the most familiar

Electromagnetic(10−2) – which manifests itself in the effects ofelectricity and magnetism.

Weak(10−7) – leads to the decay of neutrons (which underlies manynatural occurrences of radioactivity) and allows the conversion of aproton into a neutron (responsible for hydrogen burning in thecentre of stars).

Strong(1) – holds quarks together within protons, neutrons andother particles. It also prevents the protons in the nucleus fromflying apart under the influence of the repulsive electrical forcebetween them (they all have positive charge!).

Each of these has its own “carrier” particle!

Page 33: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

. . . and the four forces

Gravity(10−40) – the most familiar

Electromagnetic(10−2) – which manifests itself in the effects ofelectricity and magnetism.

Weak(10−7) – leads to the decay of neutrons (which underlies manynatural occurrences of radioactivity) and allows the conversion of aproton into a neutron (responsible for hydrogen burning in thecentre of stars).

Strong(1) – holds quarks together within protons, neutrons andother particles. It also prevents the protons in the nucleus fromflying apart under the influence of the repulsive electrical forcebetween them (they all have positive charge!).

Each of these has its own “carrier” particle!

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Final Picture

The work (theoretical and experimental) of thousands of physicists overmore than a century have resulted in what is called the “StandardModel” of Particle physics consisting of 12 matter particles and 4 typesof force carriers.

Two matter families–quarks and leptons

Six quarks and six leptons–organised in three families each

Page 35: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Final Picture

The work (theoretical and experimental) of thousands of physicists overmore than a century have resulted in what is called the “StandardModel” of Particle physics consisting of 12 matter particles and 4 typesof force carriers.

Two matter families–quarks and leptons

Six quarks and six leptons–organised in three families each

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The Four ForcesFinal Picture

The LHCTheory Issues

The Final Picture

“Three generations” – all second and third generation particles are unstable

and decay quickly into first generation ones. That is why first generation

particles are the only ones we observe in our daily lives.

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Final Picture

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The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model

The Standard Model is currently the best description of the world ofquarks, leptons and other particles. However it leaves many questionsunanswered. . .

What is the origin of mass of the particles?

Masses⇒Higgs mechanism⇒ Higgs particle→last and perhaps mostimportant missing part of the Standard Model

Page 39: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model

The Standard Model is currently the best description of the world ofquarks, leptons and other particles. However it leaves many questionsunanswered. . .

What is the origin of mass of the particles?

Masses⇒Higgs mechanism⇒ Higgs particle→last and perhaps mostimportant missing part of the Standard Model

Page 40: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model

The Standard Model is currently the best description of the world ofquarks, leptons and other particles. However it leaves many questionsunanswered. . .

What is the origin of mass of the particles?

Masses⇒Higgs mechanism⇒ Higgs particle→last and perhaps mostimportant missing part of the Standard Model

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The Four ForcesFinal Picture

The LHCTheory Issues

More. . .

Can the electroweak and strong forces be unified?

The SM unifies weak and electromagnetism but we expect thestrong force to be unified with the electroweak at thousand milliontimes present day accelerator energies (Grand Unified Theories).

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The Four ForcesFinal Picture

The LHCTheory Issues

More. . .

Can the electroweak and strong forces be unified?

The SM unifies weak and electromagnetism but we expect thestrong force to be unified with the electroweak at thousand milliontimes present day accelerator energies (Grand Unified Theories).

Page 43: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More. . .

Can the electroweak and strong forces be unified?

The SM unifies weak and electromagnetism but we expect thestrong force to be unified with the electroweak at thousand milliontimes present day accelerator energies (Grand Unified Theories).

Page 44: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model. . .

What is “Dark Matter” made of?

Measurements in astronomy imply that up to 90% or more of theUniverse is not visible – dark matter/energy – nature not known.

Where did anti-matter go? And why only three generations

Again, the answers are either not known or only partially known

Page 45: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model. . .

What is “Dark Matter” made of?

Measurements in astronomy imply that up to 90% or more of theUniverse is not visible – dark matter/energy – nature not known.

Where did anti-matter go? And why only three generations

Again, the answers are either not known or only partially known

Page 46: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model. . .

What is “Dark Matter” made of?

Measurements in astronomy imply that up to 90% or more of theUniverse is not visible – dark matter/energy – nature not known.

Where did anti-matter go? And why only three generations

Again, the answers are either not known or only partially known

Page 47: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model. . .

What is “Dark Matter” made of?

Measurements in astronomy imply that up to 90% or more of theUniverse is not visible – dark matter/energy – nature not known.

Where did anti-matter go? And why only three generations

Again, the answers are either not known or only partially known

Page 48: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

More on the Standard Model. . .

What is “Dark Matter” made of?

Measurements in astronomy imply that up to 90% or more of theUniverse is not visible – dark matter/energy – nature not known.

Where did anti-matter go? And why only three generations

Again, the answers are either not known or only partially known

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

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The Four ForcesFinal Picture

The LHCTheory Issues

The Theory of Everything??

The long range goal of physics is to unify all the forces, so that gravitywould be combined with the future version of the Grand Unified Theory.

Will the LHC provide any clues to this? We have to wait. . .

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Theory of Everything??

The long range goal of physics is to unify all the forces, so that gravitywould be combined with the future version of the Grand Unified Theory.

Will the LHC provide any clues to this? We have to wait. . .

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The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Back to the LHC

Particles are extremely tiny, to be able to see and study them, scientists needvery special tools.

⇒accelerators, huge machines able to speed up particles to very high energiesbefore smashing them into other particles.

Around the points where the “smashing” occurs, scientists build experiments toobserve and study the collisions⇒ huge instruments, called particle detectors.

By accelerating and smashing particles, physicists can identify their componentsor create new particles, revealing the nature of the interactions between them.

By why do we need to accelerate them to such high energies?

Page 53: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Back to the LHC

Particles are extremely tiny, to be able to see and study them, scientists needvery special tools.

⇒accelerators, huge machines able to speed up particles to very high energiesbefore smashing them into other particles.

Around the points where the “smashing” occurs, scientists build experiments toobserve and study the collisions⇒ huge instruments, called particle detectors.

By accelerating and smashing particles, physicists can identify their componentsor create new particles, revealing the nature of the interactions between them.

By why do we need to accelerate them to such high energies?

Page 54: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Back to the LHC

Particles are extremely tiny, to be able to see and study them, scientists needvery special tools.

⇒accelerators, huge machines able to speed up particles to very high energiesbefore smashing them into other particles.

Around the points where the “smashing” occurs, scientists build experiments toobserve and study the collisions⇒ huge instruments, called particle detectors.

By accelerating and smashing particles, physicists can identify their componentsor create new particles, revealing the nature of the interactions between them.

By why do we need to accelerate them to such high energies?

Page 55: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Back to the LHC

Particles are extremely tiny, to be able to see and study them, scientists needvery special tools.

⇒accelerators, huge machines able to speed up particles to very high energiesbefore smashing them into other particles.

Around the points where the “smashing” occurs, scientists build experiments toobserve and study the collisions⇒ huge instruments, called particle detectors.

By accelerating and smashing particles, physicists can identify their componentsor create new particles, revealing the nature of the interactions between them.

By why do we need to accelerate them to such high energies?

Page 56: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Back to the LHC

Particles are extremely tiny, to be able to see and study them, scientists needvery special tools.

⇒accelerators, huge machines able to speed up particles to very high energiesbefore smashing them into other particles.

Around the points where the “smashing” occurs, scientists build experiments toobserve and study the collisions⇒ huge instruments, called particle detectors.

By accelerating and smashing particles, physicists can identify their componentsor create new particles, revealing the nature of the interactions between them.

By why do we need to accelerate them to such high energies?

Page 57: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Back to the LHC

Particles are extremely tiny, to be able to see and study them, scientists needvery special tools.

⇒accelerators, huge machines able to speed up particles to very high energiesbefore smashing them into other particles.

Around the points where the “smashing” occurs, scientists build experiments toobserve and study the collisions⇒ huge instruments, called particle detectors.

By accelerating and smashing particles, physicists can identify their componentsor create new particles, revealing the nature of the interactions between them.

By why do we need to accelerate them to such high energies?

Page 58: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Matter at the subatomic scale

Physicists investigate the constituents of matter at the subatomic level,where the typical distances are of the order of the femtometre(0.000000000000001 m, or 10−15m) or smaller!

Ordinary microscope⇒ visible light λ ∼ 10−6m ⇒ objects smallercannot be resolved

Electron microscope⇒ matter wave of moving electron λ ∼ 10−9m

To “see” objects of the size of electrons and quarks (10−18, 10−19m),we need to use particles that have a billion times more energy!!!

The smaller the particle you want to see, the more energetic your probeneeds to be and hence larger the machine you have to build.

This is the reason for the colossal size of the LHC!

Page 59: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Matter at the subatomic scale

Physicists investigate the constituents of matter at the subatomic level,where the typical distances are of the order of the femtometre(0.000000000000001 m, or 10−15m) or smaller!

Ordinary microscope⇒ visible light λ ∼ 10−6m ⇒ objects smallercannot be resolved

Electron microscope⇒ matter wave of moving electron λ ∼ 10−9m

To “see” objects of the size of electrons and quarks (10−18, 10−19m),we need to use particles that have a billion times more energy!!!

The smaller the particle you want to see, the more energetic your probeneeds to be and hence larger the machine you have to build.

This is the reason for the colossal size of the LHC!

Page 60: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Matter at the subatomic scale

Physicists investigate the constituents of matter at the subatomic level,where the typical distances are of the order of the femtometre(0.000000000000001 m, or 10−15m) or smaller!

Ordinary microscope⇒ visible light λ ∼ 10−6m ⇒ objects smallercannot be resolved

Electron microscope⇒ matter wave of moving electron λ ∼ 10−9m

To “see” objects of the size of electrons and quarks (10−18, 10−19m),we need to use particles that have a billion times more energy!!!

The smaller the particle you want to see, the more energetic your probeneeds to be and hence larger the machine you have to build.

This is the reason for the colossal size of the LHC!

Page 61: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Matter at the subatomic scale

Physicists investigate the constituents of matter at the subatomic level,where the typical distances are of the order of the femtometre(0.000000000000001 m, or 10−15m) or smaller!

Ordinary microscope⇒ visible light λ ∼ 10−6m ⇒ objects smallercannot be resolved

Electron microscope⇒ matter wave of moving electron λ ∼ 10−9m

To “see” objects of the size of electrons and quarks (10−18, 10−19m),we need to use particles that have a billion times more energy!!!

The smaller the particle you want to see, the more energetic your probeneeds to be and hence larger the machine you have to build.

This is the reason for the colossal size of the LHC!

Page 62: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Matter at the subatomic scale

Physicists investigate the constituents of matter at the subatomic level,where the typical distances are of the order of the femtometre(0.000000000000001 m, or 10−15m) or smaller!

Ordinary microscope⇒ visible light λ ∼ 10−6m ⇒ objects smallercannot be resolved

Electron microscope⇒ matter wave of moving electron λ ∼ 10−9m

To “see” objects of the size of electrons and quarks (10−18, 10−19m),we need to use particles that have a billion times more energy!!!

The smaller the particle you want to see, the more energetic your probeneeds to be and hence larger the machine you have to build.

This is the reason for the colossal size of the LHC!

Page 63: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The LHC

Page 64: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The LHC

27 km ring buried 50-170m below ground near Geneva wherein high-energyprotons in two counter-rotating beams will be smashed together in a search forsignatures of supersymmetry, dark matter and the origins of mass.

The beams are made up ofbunches containing billions ofprotons, traveling almost at thespeed of light

The beams travel in twoseparate vacuum pipes, exceptat four collision points wherethey collide in the hearts of themain experiments, ALICE,ATLAS, CMS, and LHCb.

The detectors can see up to 600 million collision events per second,searching the data for signs of extremely rare events such as the creationof the much-sought after Higgs boson.

Page 65: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The LHC

27 km ring buried 50-170m below ground near Geneva wherein high-energyprotons in two counter-rotating beams will be smashed together in a search forsignatures of supersymmetry, dark matter and the origins of mass.

The beams are made up ofbunches containing billions ofprotons, traveling almost at thespeed of light

The beams travel in twoseparate vacuum pipes, exceptat four collision points wherethey collide in the hearts of themain experiments, ALICE,ATLAS, CMS, and LHCb.

The detectors can see up to 600 million collision events per second,searching the data for signs of extremely rare events such as the creationof the much-sought after Higgs boson.

Page 66: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The LHC

27 km ring buried 50-170m below ground near Geneva wherein high-energyprotons in two counter-rotating beams will be smashed together in a search forsignatures of supersymmetry, dark matter and the origins of mass.

The beams are made up ofbunches containing billions ofprotons, traveling almost at thespeed of light

The beams travel in twoseparate vacuum pipes, exceptat four collision points wherethey collide in the hearts of themain experiments, ALICE,ATLAS, CMS, and LHCb.

The detectors can see up to 600 million collision events per second,searching the data for signs of extremely rare events such as the creationof the much-sought after Higgs boson.

Page 67: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The LHC

27 km ring buried 50-170m below ground near Geneva wherein high-energyprotons in two counter-rotating beams will be smashed together in a search forsignatures of supersymmetry, dark matter and the origins of mass.

The beams are made up ofbunches containing billions ofprotons, traveling almost at thespeed of light

The beams travel in twoseparate vacuum pipes, exceptat four collision points wherethey collide in the hearts of themain experiments, ALICE,ATLAS, CMS, and LHCb.

The detectors can see up to 600 million collision events per second,searching the data for signs of extremely rare events such as the creationof the much-sought after Higgs boson.

Page 68: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Collision process

At 0.999999991c, bunches(1.15× 1011 protons) collidehead-on at each collisonpoint about 40 million timesper second.

Each collision only producesabout 20 collisions betweenthe protons ⇒ about abillion collisions per second.

Of these only about 10-100are of scientific interest!!Unravelling these from therest is the real challenge!

Page 69: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Collision process

At 0.999999991c, bunches(1.15× 1011 protons) collidehead-on at each collisonpoint about 40 million timesper second.

Each collision only producesabout 20 collisions betweenthe protons ⇒ about abillion collisions per second.

Of these only about 10-100are of scientific interest!!Unravelling these from therest is the real challenge!

Page 70: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Collision process

At 0.999999991c, bunches(1.15× 1011 protons) collidehead-on at each collisonpoint about 40 million timesper second.

Each collision only producesabout 20 collisions betweenthe protons ⇒ about abillion collisions per second.

Of these only about 10-100are of scientific interest!!Unravelling these from therest is the real challenge!

Page 71: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Collision process

At 0.999999991c, bunches(1.15× 1011 protons) collidehead-on at each collisonpoint about 40 million timesper second.

Each collision only producesabout 20 collisions betweenthe protons ⇒ about abillion collisions per second.

Of these only about 10-100are of scientific interest!!Unravelling these from therest is the real challenge!

Page 72: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Simulation of a Higgs decay event

Page 73: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Event filtering and triggers

Event size ∼ 1 MbyteOne billion collision ∼ 109 Mbyte of data per secondPresent technology and budget ∼ 100 Mbytes per second to tape⇒ factor of 107 on line filtering!!!

Totaldata readout/year ⇒ ∼ 1 PByte (109MB)

The event trigger is a major technological challenge — depends onsignatures like jets, lepton, photons, missing E⊥ . . .

Page 74: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

The beams are kept in orbit by using superconducting magnetsalong the path of the beam.

The main budget item and a serious technological challenge are thesuperconducting (1.9 K) dipoles which bend the beams.

At 7 TeV these magnets have to produce a field of around 8.4 Tesla(100,000 times the Earth’s magnetic field) at a current of around11,700 A.

There are a total of 1232 such magnets each 14.3m long.

The total length of superconducting cable used is ∼ 270,000 km.

Page 75: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

The beams are kept in orbit by using superconducting magnetsalong the path of the beam.

The main budget item and a serious technological challenge are thesuperconducting (1.9 K) dipoles which bend the beams.

At 7 TeV these magnets have to produce a field of around 8.4 Tesla(100,000 times the Earth’s magnetic field) at a current of around11,700 A.

There are a total of 1232 such magnets each 14.3m long.

The total length of superconducting cable used is ∼ 270,000 km.

Page 76: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

The beams are kept in orbit by using superconducting magnetsalong the path of the beam.

The main budget item and a serious technological challenge are thesuperconducting (1.9 K) dipoles which bend the beams.

At 7 TeV these magnets have to produce a field of around 8.4 Tesla(100,000 times the Earth’s magnetic field) at a current of around11,700 A.

There are a total of 1232 such magnets each 14.3m long.

The total length of superconducting cable used is ∼ 270,000 km.

Page 77: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

The beams are kept in orbit by using superconducting magnetsalong the path of the beam.

The main budget item and a serious technological challenge are thesuperconducting (1.9 K) dipoles which bend the beams.

At 7 TeV these magnets have to produce a field of around 8.4 Tesla(100,000 times the Earth’s magnetic field) at a current of around11,700 A.

There are a total of 1232 such magnets each 14.3m long.

The total length of superconducting cable used is ∼ 270,000 km.

Page 78: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

The beams are kept in orbit by using superconducting magnetsalong the path of the beam.

The main budget item and a serious technological challenge are thesuperconducting (1.9 K) dipoles which bend the beams.

At 7 TeV these magnets have to produce a field of around 8.4 Tesla(100,000 times the Earth’s magnetic field) at a current of around11,700 A.

There are a total of 1232 such magnets each 14.3m long.

The total length of superconducting cable used is ∼ 270,000 km.

Page 79: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

The beams are kept in orbit by using superconducting magnetsalong the path of the beam.

The main budget item and a serious technological challenge are thesuperconducting (1.9 K) dipoles which bend the beams.

At 7 TeV these magnets have to produce a field of around 8.4 Tesla(100,000 times the Earth’s magnetic field) at a current of around11,700 A.

There are a total of 1232 such magnets each 14.3m long.

The total length of superconducting cable used is ∼ 270,000 km.

Page 80: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

The LHC will operate at 1.9K, even colder than outer space.With its 27 km circumference, the accelerator will be the largest

superconducting installation in the worldIt takes months to bring the whole system of magnets down to this

temperature.

Page 81: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Superconducting Magnets

Page 82: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Detectors

Page 83: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Detectors

Page 84: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Detectors

Page 85: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Detectors

Page 86: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Detectors

Page 87: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Detectors

Page 88: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Detectors

Two major general purposedetectorsCMS:180 inst.,38countries, ∼ 2000 authorsATLAS:164 inst., 35countries, ∼ 1800 authors

Page 89: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 90: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 91: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 92: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 93: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 94: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 95: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 96: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Interesting facts about the LHC

Typical weight of a detector (CMS) – 13000 tons (30% more thanthe Eiffel Tower)

Typical length of cable used in one detector (ATLAS) – 3000 km

Data volume expected per year – few PB (1PB = 106GB) afterfiltering

The kinetic energy of the beam:(2808 bunches per beam)×1.15× 1011 protons per bunch ×7TeV(=1.8 ergs)= 377 MJ⇒ a train of 103 tons going at 140 km/h.

Machine temperature– 1.9K (largest cryogenic system in the world)

Total cost – 4 billion dollars

Total number of involved physicists – 5000

Page 97: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Fun-facts

Vacuum inside LHC beam pipe ∼ 10−10 Torr (MSL: 760 Torr)

The moon and snow/water load on the Jura mountains flexes theearth’s crust a little bit (tidal effects on land) which alters thecircumference of the LHC ring - these need to be compensated.

Page 98: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Fun-facts

Vacuum inside LHC beam pipe ∼ 10−10 Torr (MSL: 760 Torr)

The moon and snow/water load on the Jura mountains flexes theearth’s crust a little bit (tidal effects on land) which alters thecircumference of the LHC ring - these need to be compensated.

Page 99: The Large Hadron Collider   The Worlds Largest Microscope

The Large Hadron ColliderThe Structure of Matter

The Four ForcesFinal Picture

The LHCTheory Issues

The Collision ProcessSuperconducting Bending MagnetsThe Detectors

Fun-facts

Vacuum inside LHC beam pipe ∼ 10−10 Torr (MSL: 760 Torr)

The moon and snow/water load on the Jura mountains flexes theearth’s crust a little bit (tidal effects on land) which alters thecircumference of the LHC ring - these need to be compensated.

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The Collision ProcessSuperconducting Bending MagnetsThe Detectors

The Future

First Beam Aug 2008

First Collisions Sep 2008 at 5 TeV

First physics run early 2009

Full luminosity and energy physics runs late 2009

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Theory Issues

The very first and major role for the LHC is the discovery of the Higgsboson (if the Tevatron does not get to it first)

⇓This will merely complete the Standard Model

⇓Search for New Physics

New Physics (Beyond Standard Model (BSM) physics) needed to answermany questions → Higgs mass stabilisation, CP violation, dark matter,naturalness, gravity, gauge unification. . .

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P-P Complications

Since the protons have substructure, the collision is a mess

We need to separate the known physics to get to the unknown physics

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P-P Complications

Most of 2009 will go in rediscovering the Standard Model at 14 TeV

Comparing with calculations and generators

Tuning the generators and from there to understand and calibratedetectors⇒ The road will discovery will be long and hard..

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Understanding QCD

QCD effects are very large and important at 14 TeV. Need to understand

PDF’s

Jet Physics

Diffraction

BFKL studies

low x

at these energies to get New Physics. In addition, a whole lot on topphysics, b physics...

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Higgs Physics

Understand the origin of the Electro-weak Symmetry BreakingmechanismThe SM has just one Higgs which is a fundamental scalar particle(the first of its kind) - are there others?We hope that the LHC will discover the Higgs at mH < 1TeVEase of discovery dictated by decay channel and pollution bybackground

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New Physics

We expect Beyond Standard Model Physics (BSM) around the TeV scaleto provide solutions to problems of

Higgs mass stabilisation,

Gauge hierarchy

Unification of couplings

Nature of Cold Dark Matter

. . .

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Supersymmetry

For every Standard Model Particle, there is a Supersymmetric partner →selectron, squarks, higgsino . . .Status: Not seen yet, maybe around the corner. . .

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Extra Dimensions

Particle physics is confinedto a brane and interactswith extra dimensions andother ’hidden dimensions’through gravitons.(Randall Sundramscenario) In the ADDscenario, one can havegraviton production whichmanifests itself as missingenergy.

If Planck scale comes down to the TeV region, can have Black Holeproduction!!Status: Not seen yet, maybe around the corner. . .

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Extra Dimensions

Particle physics is confinedto a brane and interactswith extra dimensions andother ’hidden dimensions’through gravitons.(Randall Sundramscenario) In the ADDscenario, one can havegraviton production whichmanifests itself as missingenergy.

If Planck scale comes down to the TeV region, can have Black Holeproduction!!Status: Not seen yet, maybe around the corner. . .

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Extra Dimensions

Particle physics is confinedto a brane and interactswith extra dimensions andother ’hidden dimensions’through gravitons.(Randall Sundramscenario) In the ADDscenario, one can havegraviton production whichmanifests itself as missingenergy.

If Planck scale comes down to the TeV region, can have Black Holeproduction!!Status: Not seen yet, maybe around the corner. . .

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A Lot of Ideas...

There are many other scenarios:

Little Higgs

Split SUSY

Compositeness

Technicolor

heavy leptons

....

Need to identify different signatures for each of these – challenge fortheorists and experimentalists. Status: Not seen yet...

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Summary

LHC expected to start “very soon” - at 5 TeV

With a factor of 7 jump in energy from present day accelerators, theLHC will (hopefully) provide us a whole new world of TeV physics.

Hunt for new physics – but very challenging to unravel differentsignatures and identify the relevant physics

Many years of data taking and analysis ahead of us

Theory and Experiment have to work very closely together to makesense of the enormous amount of data that will be produced

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No better time to get into High Energy Physics