Download The Large Hadron Collider - the World`s Largest Microscope

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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
1
The Large Hadron Collider
Need for a Collider
2
The Structure of Matter
The Fundamental Particles
3
The Four Forces
4
Final Picture
5
The LHC
The Collision Process
Superconducting Bending Magnets
The Detectors
6
Theory Issues
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Need for a Collider
The Large Hadron Collider
Large Hadron Collider
⇓
An enormous particle
accelerator due to become
operational in August 2008
that will collide beams of
protons at an energy of 14
TeV (and eventually lead
nuclei of energy 1150
TeV).
Figure: 27 km circumference ring
TeV: Unit of energy used in particle physics ' 1.6 ergs – about the
energy of a flying mosquito – but squeezed into a space a billion (million
million) times smaller.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Need for a Collider
The Large Hadron Collider
Large Hadron Collider
⇓
An enormous particle
accelerator due to become
operational in August 2008
that will collide beams of
protons at an energy of 14
TeV (and eventually lead
nuclei of energy 1150
TeV).
Figure: 27 km circumference ring
TeV: Unit of energy used in particle physics ' 1.6 ergs – about the
energy of a flying mosquito – but squeezed into a space a billion (million
million) times smaller.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Need for a Collider
CERN – where the Web was born
CERN is the European Organization for Nuclear Research, the world’s largest
particle physics centre sitting astride the Franco-Swiss border near Geneva.
CERN is a laboratory where scientists unite to study the building blocks of
matter and the forces that hold them together. CERN exists primarily to
provide them with the necessary tools. These are accelerators, which accelerate
particles to almost the speed of light and detectors to make the particles
visible. (It is also where the World Wide Web was born!)
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Need for a Collider
LHC - machine and experiments
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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 with
the discovery of radioactivity and subsequently, alpha, beta, gamma rays,
X rays, and many new particles as the fundamental building blocks of
nature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )
Today we know what these particles are but along the way many new
questions have arisen which need to be answered (along the way, many of
these discoveries have also given us TV’s, computers, medical imaging
devices, . . . )
The LHC is built to answer many of these new questions as we stand on
the threshold of this new century.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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 with
the discovery of radioactivity and subsequently, alpha, beta, gamma rays,
X rays, and many new particles as the fundamental building blocks of
nature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )
Today we know what these particles are but along the way many new
questions have arisen which need to be answered (along the way, many of
these discoveries have also given us TV’s, computers, medical imaging
devices, . . . )
The LHC is built to answer many of these new questions as we stand on
the threshold of this new century.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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 with
the discovery of radioactivity and subsequently, alpha, beta, gamma rays,
X rays, and many new particles as the fundamental building blocks of
nature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )
Today we know what these particles are but along the way many new
questions have arisen which need to be answered (along the way, many of
these discoveries have also given us TV’s, computers, medical imaging
devices, . . . )
The LHC is built to answer many of these new questions as we stand on
the threshold of this new century.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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 with
the discovery of radioactivity and subsequently, alpha, beta, gamma rays,
X rays, and many new particles as the fundamental building blocks of
nature.(Tevatron, LEP, SPS, HERA, SLAC, . . . )
Today we know what these particles are but along the way many new
questions have arisen which need to be answered (along the way, many of
these discoveries have also given us TV’s, computers, medical imaging
devices, . . . )
The LHC is built to answer many of these new questions as we stand on
the threshold of this new century.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
But why study the structure of Matter?
Universe is built up of building
blocks (elementary particles)
All these particles existed in the
short time just after the Big
Bang but no longer. . .
Can only be created in high
energy 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!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
But why study the structure of Matter?
Universe is built up of building
blocks (elementary particles)
All these particles existed in the
short time just after the Big
Bang but no longer. . .
Can only be created in high
energy 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!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
But why study the structure of Matter?
Universe is built up of building
blocks (elementary particles)
All these particles existed in the
short time just after the Big
Bang but no longer. . .
Can only be created in high
energy 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!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
But why study the structure of Matter?
Universe is built up of building
blocks (elementary particles)
All these particles existed in the
short time just after the Big
Bang but no longer. . .
Can only be created in high
energy 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!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
But why study the structure of Matter?
Universe is built up of building
blocks (elementary particles)
All these particles existed in the
short time just after the Big
Bang but no longer. . .
Can only be created in high
energy 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!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
But why study the structure of Matter?
Universe is built up of building
blocks (elementary particles)
All these particles existed in the
short time just after the Big
Bang but no longer. . .
Can only be created in high
energy 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!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
Let’s start at the very beginning. . .
Everything in the Universe is built up of basic building blocks called
elementary particles
Matter
⇒ atoms
⇒ electrons and nucleus
⇒ protons and neutrons
⇒ quarks
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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. It
plays a vital role in reactions that convert neutrons to protons and
vice versa. Such reactions allow matter to stay in the stable form we
observe and are also important in fuelling the Sun and the other
stars.
These four particles are all we need to build the ordinary matter we
see 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.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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. It
plays a vital role in reactions that convert neutrons to protons and
vice versa. Such reactions allow matter to stay in the stable form we
observe and are also important in fuelling the Sun and the other
stars.
These four particles are all we need to build the ordinary matter we
see 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.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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. It
plays a vital role in reactions that convert neutrons to protons and
vice versa. Such reactions allow matter to stay in the stable form we
observe and are also important in fuelling the Sun and the other
stars.
These four particles are all we need to build the ordinary matter we
see 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.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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. It
plays a vital role in reactions that convert neutrons to protons and
vice versa. Such reactions allow matter to stay in the stable form we
observe and are also important in fuelling the Sun and the other
stars.
These four particles are all we need to build the ordinary matter we
see 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.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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. It
plays a vital role in reactions that convert neutrons to protons and
vice versa. Such reactions allow matter to stay in the stable form we
observe and are also important in fuelling the Sun and the other
stars.
These four particles are all we need to build the ordinary matter we
see 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.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
Anti-Matter
Matter and antimatter are perfect opposites; for each of the basic
particles of matter, there exists an antiparticle, in which properties such
as the electric charge are reversed.
When matter and
antimatter meet, they
annihilate each other,
creating energy (2mc 2 - 1
gm ∼ 107 MJ ∼ 2kt TNT)
which reappears as
photons or other
particle-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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
Anti-Matter
Matter and antimatter are perfect opposites; for each of the basic
particles of matter, there exists an antiparticle, in which properties such
as the electric charge are reversed.
When matter and
antimatter meet, they
annihilate each other,
creating energy (2mc 2 - 1
gm ∼ 107 MJ ∼ 2kt TNT)
which reappears as
photons or other
particle-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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Fundamental Particles
Anti-Matter
Matter and antimatter are perfect opposites; for each of the basic
particles of matter, there exists an antiparticle, in which properties such
as the electric charge are reversed.
When matter and
antimatter meet, they
annihilate each other,
creating energy (2mc 2 - 1
gm ∼ 107 MJ ∼ 2kt TNT)
which reappears as
photons or other
particle-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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
. . . and the four forces
Gravity(10−40 ) – the most familiar
Electromagnetic(10−2 ) – which manifests itself in the effects of
electricity and magnetism.
Weak(10−7 ) – leads to the decay of neutrons (which underlies many
natural occurrences of radioactivity) and allows the conversion of a
proton into a neutron (responsible for hydrogen burning in the
centre of stars).
Strong(1) – holds quarks together within protons, neutrons and
other particles. It also prevents the protons in the nucleus from
flying apart under the influence of the repulsive electrical force
between them (they all have positive charge!).
Each of these has its own “carrier” particle!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
. . . and the four forces
Gravity(10−40 ) – the most familiar
Electromagnetic(10−2 ) – which manifests itself in the effects of
electricity and magnetism.
Weak(10−7 ) – leads to the decay of neutrons (which underlies many
natural occurrences of radioactivity) and allows the conversion of a
proton into a neutron (responsible for hydrogen burning in the
centre of stars).
Strong(1) – holds quarks together within protons, neutrons and
other particles. It also prevents the protons in the nucleus from
flying apart under the influence of the repulsive electrical force
between them (they all have positive charge!).
Each of these has its own “carrier” particle!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
. . . and the four forces
Gravity(10−40 ) – the most familiar
Electromagnetic(10−2 ) – which manifests itself in the effects of
electricity and magnetism.
Weak(10−7 ) – leads to the decay of neutrons (which underlies many
natural occurrences of radioactivity) and allows the conversion of a
proton into a neutron (responsible for hydrogen burning in the
centre of stars).
Strong(1) – holds quarks together within protons, neutrons and
other particles. It also prevents the protons in the nucleus from
flying apart under the influence of the repulsive electrical force
between them (they all have positive charge!).
Each of these has its own “carrier” particle!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
. . . and the four forces
Gravity(10−40 ) – the most familiar
Electromagnetic(10−2 ) – which manifests itself in the effects of
electricity and magnetism.
Weak(10−7 ) – leads to the decay of neutrons (which underlies many
natural occurrences of radioactivity) and allows the conversion of a
proton into a neutron (responsible for hydrogen burning in the
centre of stars).
Strong(1) – holds quarks together within protons, neutrons and
other particles. It also prevents the protons in the nucleus from
flying apart under the influence of the repulsive electrical force
between them (they all have positive charge!).
Each of these has its own “carrier” particle!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
. . . and the four forces
Gravity(10−40 ) – the most familiar
Electromagnetic(10−2 ) – which manifests itself in the effects of
electricity and magnetism.
Weak(10−7 ) – leads to the decay of neutrons (which underlies many
natural occurrences of radioactivity) and allows the conversion of a
proton into a neutron (responsible for hydrogen burning in the
centre of stars).
Strong(1) – holds quarks together within protons, neutrons and
other particles. It also prevents the protons in the nucleus from
flying apart under the influence of the repulsive electrical force
between them (they all have positive charge!).
Each of these has its own “carrier” particle!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
. . . and the four forces
Gravity(10−40 ) – the most familiar
Electromagnetic(10−2 ) – which manifests itself in the effects of
electricity and magnetism.
Weak(10−7 ) – leads to the decay of neutrons (which underlies many
natural occurrences of radioactivity) and allows the conversion of a
proton into a neutron (responsible for hydrogen burning in the
centre of stars).
Strong(1) – holds quarks together within protons, neutrons and
other particles. It also prevents the protons in the nucleus from
flying apart under the influence of the repulsive electrical force
between them (they all have positive charge!).
Each of these has its own “carrier” particle!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Final Picture
The work (theoretical and experimental) of thousands of physicists over
more than a century have resulted in what is called the “Standard
Model” of Particle physics consisting of 12 matter particles and 4 types
of force carriers.
Two matter families–quarks and leptons
Six quarks and six leptons–organised in three families each
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Final Picture
The work (theoretical and experimental) of thousands of physicists over
more than a century have resulted in what is called the “Standard
Model” of Particle physics consisting of 12 matter particles and 4 types
of force carriers.
Two matter families–quarks and leptons
Six quarks and six leptons–organised in three families each
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory 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.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Final Picture
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model
The Standard Model is currently the best description of the world of
quarks, leptons and other particles. However it leaves many questions
unanswered. . .
What is the origin of mass of the particles?
Masses⇒Higgs mechanism⇒ Higgs particle→last and perhaps most
important missing part of the Standard Model
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model
The Standard Model is currently the best description of the world of
quarks, leptons and other particles. However it leaves many questions
unanswered. . .
What is the origin of mass of the particles?
Masses⇒Higgs mechanism⇒ Higgs particle→last and perhaps most
important missing part of the Standard Model
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model
The Standard Model is currently the best description of the world of
quarks, leptons and other particles. However it leaves many questions
unanswered. . .
What is the origin of mass of the particles?
Masses⇒Higgs mechanism⇒ Higgs particle→last and perhaps most
important missing part of the Standard Model
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More. . .
Can the electroweak and strong forces be unified?
The SM unifies weak and electromagnetism but we expect the
strong force to be unified with the electroweak at thousand million
times present day accelerator energies (Grand Unified Theories).
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More. . .
Can the electroweak and strong forces be unified?
The SM unifies weak and electromagnetism but we expect the
strong force to be unified with the electroweak at thousand million
times present day accelerator energies (Grand Unified Theories).
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More. . .
Can the electroweak and strong forces be unified?
The SM unifies weak and electromagnetism but we expect the
strong force to be unified with the electroweak at thousand million
times present day accelerator energies (Grand Unified Theories).
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model. . .
What is “Dark Matter” made of?
Measurements in astronomy imply that up to 90% or more of the
Universe 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model. . .
What is “Dark Matter” made of?
Measurements in astronomy imply that up to 90% or more of the
Universe 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model. . .
What is “Dark Matter” made of?
Measurements in astronomy imply that up to 90% or more of the
Universe 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model. . .
What is “Dark Matter” made of?
Measurements in astronomy imply that up to 90% or more of the
Universe 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
More on the Standard Model. . .
What is “Dark Matter” made of?
Measurements in astronomy imply that up to 90% or more of the
Universe 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Theory of Everything??
The long range goal of physics is to unify all the forces, so that gravity
would be combined with the future version of the Grand Unified Theory.
Will the LHC provide any clues to this? We have to wait. . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Theory of Everything??
The long range goal of physics is to unify all the forces, so that gravity
would be combined with the future version of the Grand Unified Theory.
Will the LHC provide any clues to this? We have to wait. . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Back to the LHC
Particles are extremely tiny, to be able to see and study them, scientists need
very special tools.
⇒accelerators, huge machines able to speed up particles to very high energies
before smashing them into other particles.
Around the points where the “smashing” occurs, scientists build experiments to
observe and study the collisions⇒ huge instruments, called particle detectors.
By accelerating and smashing particles, physicists can identify their components
or create new particles, revealing the nature of the interactions between them.
By why do we need to accelerate them to such high energies?
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Back to the LHC
Particles are extremely tiny, to be able to see and study them, scientists need
very special tools.
⇒accelerators, huge machines able to speed up particles to very high energies
before smashing them into other particles.
Around the points where the “smashing” occurs, scientists build experiments to
observe and study the collisions⇒ huge instruments, called particle detectors.
By accelerating and smashing particles, physicists can identify their components
or create new particles, revealing the nature of the interactions between them.
By why do we need to accelerate them to such high energies?
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Back to the LHC
Particles are extremely tiny, to be able to see and study them, scientists need
very special tools.
⇒accelerators, huge machines able to speed up particles to very high energies
before smashing them into other particles.
Around the points where the “smashing” occurs, scientists build experiments to
observe and study the collisions⇒ huge instruments, called particle detectors.
By accelerating and smashing particles, physicists can identify their components
or create new particles, revealing the nature of the interactions between them.
By why do we need to accelerate them to such high energies?
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Back to the LHC
Particles are extremely tiny, to be able to see and study them, scientists need
very special tools.
⇒accelerators, huge machines able to speed up particles to very high energies
before smashing them into other particles.
Around the points where the “smashing” occurs, scientists build experiments to
observe and study the collisions⇒ huge instruments, called particle detectors.
By accelerating and smashing particles, physicists can identify their components
or create new particles, revealing the nature of the interactions between them.
By why do we need to accelerate them to such high energies?
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Back to the LHC
Particles are extremely tiny, to be able to see and study them, scientists need
very special tools.
⇒accelerators, huge machines able to speed up particles to very high energies
before smashing them into other particles.
Around the points where the “smashing” occurs, scientists build experiments to
observe and study the collisions⇒ huge instruments, called particle detectors.
By accelerating and smashing particles, physicists can identify their components
or create new particles, revealing the nature of the interactions between them.
By why do we need to accelerate them to such high energies?
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Back to the LHC
Particles are extremely tiny, to be able to see and study them, scientists need
very special tools.
⇒accelerators, huge machines able to speed up particles to very high energies
before smashing them into other particles.
Around the points where the “smashing” occurs, scientists build experiments to
observe and study the collisions⇒ huge instruments, called particle detectors.
By accelerating and smashing particles, physicists can identify their components
or create new particles, revealing the nature of the interactions between them.
By why do we need to accelerate them to such high energies?
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 10−15 m) or smaller!
Ordinary microscope⇒ visible light λ ∼ 10−6 m ⇒ objects smaller
cannot be resolved
Electron microscope⇒ matter wave of moving electron λ ∼ 10−9 m
To “see” objects of the size of electrons and quarks (10−18 , 10−19 m),
we need to use particles that have a billion times more energy!!!
The smaller the particle you want to see, the more energetic your probe
needs to be and hence larger the machine you have to build.
This is the reason for the colossal size of the LHC!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 10−15 m) or smaller!
Ordinary microscope⇒ visible light λ ∼ 10−6 m ⇒ objects smaller
cannot be resolved
Electron microscope⇒ matter wave of moving electron λ ∼ 10−9 m
To “see” objects of the size of electrons and quarks (10−18 , 10−19 m),
we need to use particles that have a billion times more energy!!!
The smaller the particle you want to see, the more energetic your probe
needs to be and hence larger the machine you have to build.
This is the reason for the colossal size of the LHC!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 10−15 m) or smaller!
Ordinary microscope⇒ visible light λ ∼ 10−6 m ⇒ objects smaller
cannot be resolved
Electron microscope⇒ matter wave of moving electron λ ∼ 10−9 m
To “see” objects of the size of electrons and quarks (10−18 , 10−19 m),
we need to use particles that have a billion times more energy!!!
The smaller the particle you want to see, the more energetic your probe
needs to be and hence larger the machine you have to build.
This is the reason for the colossal size of the LHC!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 10−15 m) or smaller!
Ordinary microscope⇒ visible light λ ∼ 10−6 m ⇒ objects smaller
cannot be resolved
Electron microscope⇒ matter wave of moving electron λ ∼ 10−9 m
To “see” objects of the size of electrons and quarks (10−18 , 10−19 m),
we need to use particles that have a billion times more energy!!!
The smaller the particle you want to see, the more energetic your probe
needs to be and hence larger the machine you have to build.
This is the reason for the colossal size of the LHC!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 10−15 m) or smaller!
Ordinary microscope⇒ visible light λ ∼ 10−6 m ⇒ objects smaller
cannot be resolved
Electron microscope⇒ matter wave of moving electron λ ∼ 10−9 m
To “see” objects of the size of electrons and quarks (10−18 , 10−19 m),
we need to use particles that have a billion times more energy!!!
The smaller the particle you want to see, the more energetic your probe
needs to be and hence larger the machine you have to build.
This is the reason for the colossal size of the LHC!
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The LHC
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
The LHC
27 km ring buried 50-170m below ground near Geneva wherein high-energy
protons in two counter-rotating beams will be smashed together in a search for
signatures of supersymmetry, dark matter and the origins of mass.
The beams are made up of
bunches containing billions of
protons, traveling almost at the
speed of light
The beams travel in two
separate vacuum pipes, except
at four collision points where
they collide in the hearts of the
main 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 creation
of the much-sought after Higgs boson.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
The LHC
27 km ring buried 50-170m below ground near Geneva wherein high-energy
protons in two counter-rotating beams will be smashed together in a search for
signatures of supersymmetry, dark matter and the origins of mass.
The beams are made up of
bunches containing billions of
protons, traveling almost at the
speed of light
The beams travel in two
separate vacuum pipes, except
at four collision points where
they collide in the hearts of the
main 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 creation
of the much-sought after Higgs boson.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
The LHC
27 km ring buried 50-170m below ground near Geneva wherein high-energy
protons in two counter-rotating beams will be smashed together in a search for
signatures of supersymmetry, dark matter and the origins of mass.
The beams are made up of
bunches containing billions of
protons, traveling almost at the
speed of light
The beams travel in two
separate vacuum pipes, except
at four collision points where
they collide in the hearts of the
main 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 creation
of the much-sought after Higgs boson.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
The LHC
27 km ring buried 50-170m below ground near Geneva wherein high-energy
protons in two counter-rotating beams will be smashed together in a search for
signatures of supersymmetry, dark matter and the origins of mass.
The beams are made up of
bunches containing billions of
protons, traveling almost at the
speed of light
The beams travel in two
separate vacuum pipes, except
at four collision points where
they collide in the hearts of the
main 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 creation
of the much-sought after Higgs boson.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision process
At 0.999999991c, bunches
(1.15 × 1011 protons) collide
head-on at each collison
point about 40 million times
per second.
Each collision only produces
about 20 collisions between
the protons ⇒ about a
billion collisions per second.
Of these only about 10-100
are of scientific interest!!
Unravelling these from the
rest is the real challenge!
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision process
At 0.999999991c, bunches
(1.15 × 1011 protons) collide
head-on at each collison
point about 40 million times
per second.
Each collision only produces
about 20 collisions between
the protons ⇒ about a
billion collisions per second.
Of these only about 10-100
are of scientific interest!!
Unravelling these from the
rest is the real challenge!
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision process
At 0.999999991c, bunches
(1.15 × 1011 protons) collide
head-on at each collison
point about 40 million times
per second.
Each collision only produces
about 20 collisions between
the protons ⇒ about a
billion collisions per second.
Of these only about 10-100
are of scientific interest!!
Unravelling these from the
rest is the real challenge!
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision process
At 0.999999991c, bunches
(1.15 × 1011 protons) collide
head-on at each collison
point about 40 million times
per second.
Each collision only produces
about 20 collisions between
the protons ⇒ about a
billion collisions per second.
Of these only about 10-100
are of scientific interest!!
Unravelling these from the
rest is the real challenge!
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Simulation of a Higgs decay event
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Event filtering and triggers
Event size ∼ 1 Mbyte
One billion collision ∼ 109 Mbyte of data per second
Present technology and budget ∼ 100 Mbytes per second to tape
⇒ factor of 107 on line filtering!!!
data readout/year ⇒ ∼ 1 PByte (109 MB)
The event trigger is a major technological challenge — depends on
signatures like jets, lepton, photons, missing E⊥ . . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Superconducting Magnets
The beams are kept in orbit by using superconducting magnets
along the path of the beam.
The main budget item and a serious technological challenge are the
superconducting (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 around
11,700 A.
There are a total of 1232 such magnets each 14.3m long.
The total length of superconducting cable used is ∼ 270,000 km.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Superconducting Magnets
The beams are kept in orbit by using superconducting magnets
along the path of the beam.
The main budget item and a serious technological challenge are the
superconducting (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 around
11,700 A.
There are a total of 1232 such magnets each 14.3m long.
The total length of superconducting cable used is ∼ 270,000 km.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Superconducting Magnets
The beams are kept in orbit by using superconducting magnets
along the path of the beam.
The main budget item and a serious technological challenge are the
superconducting (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 around
11,700 A.
There are a total of 1232 such magnets each 14.3m long.
The total length of superconducting cable used is ∼ 270,000 km.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Superconducting Magnets
The beams are kept in orbit by using superconducting magnets
along the path of the beam.
The main budget item and a serious technological challenge are the
superconducting (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 around
11,700 A.
There are a total of 1232 such magnets each 14.3m long.
The total length of superconducting cable used is ∼ 270,000 km.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Superconducting Magnets
The beams are kept in orbit by using superconducting magnets
along the path of the beam.
The main budget item and a serious technological challenge are the
superconducting (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 around
11,700 A.
There are a total of 1232 such magnets each 14.3m long.
The total length of superconducting cable used is ∼ 270,000 km.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Superconducting Magnets
The beams are kept in orbit by using superconducting magnets
along the path of the beam.
The main budget item and a serious technological challenge are the
superconducting (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 around
11,700 A.
There are a total of 1232 such magnets each 14.3m long.
The total length of superconducting cable used is ∼ 270,000 km.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 world
It takes months to bring the whole system of magnets down to this
temperature.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Superconducting Magnets
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Detectors
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Detectors
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Detectors
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Detectors
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Detectors
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Detectors
The Collision Process
Superconducting Bending Magnets
The Detectors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
The Detectors
Two major general purpose
detectors
CMS:180 inst.,38
countries, ∼ 2000 authors
ATLAS:164 inst., 35
countries, ∼ 1800 authors
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The Detectors
Interesting facts about the LHC
Typical weight of a detector (CMS) – 13000 tons (30% more than
the Eiffel Tower)
Typical length of cable used in one detector (ATLAS) – 3000 km
Data volume expected per year – few PB (1PB = 106 GB) after
filtering
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 the
earth’s crust a little bit (tidal effects on land) which alters the
circumference of the LHC ring - these need to be compensated.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 the
earth’s crust a little bit (tidal effects on land) which alters the
circumference of the LHC ring - these need to be compensated.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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 the
earth’s crust a little bit (tidal effects on land) which alters the
circumference of the LHC ring - these need to be compensated.
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
The Collision Process
Superconducting Bending Magnets
The 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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Theory Issues
The very first and major role for the LHC is the discovery of the Higgs
boson (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 answer
many questions → Higgs mass stabilisation, CP violation, dark matter,
naturalness, gravity, gauge unification. . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
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
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
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 calibrate
detectors
⇒ The road will discovery will be long and hard..
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
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 top
physics, b physics...
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Higgs Physics
Understand the origin of the Electro-weak Symmetry Breaking
mechanism
The 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 < 1TeV
Ease of discovery dictated by decay channel and pollution by
background
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
New Physics
We expect Beyond Standard Model Physics (BSM) around the TeV scale
to provide solutions to problems of
Higgs mass stabilisation,
Gauge hierarchy
Unification of couplings
Nature of Cold Dark Matter
...
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Supersymmetry
For every Standard Model Particle, there is a Supersymmetric partner →
selectron, squarks, higgsino . . .
Status: Not seen yet, maybe around the corner. . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Extra Dimensions
Particle physics is confined
to a brane and interacts
with extra dimensions and
other ’hidden dimensions’
through gravitons.
(Randall Sundram
scenario) In the ADD
scenario, one can have
graviton production which
manifests itself as missing
energy.
If Planck scale comes down to the TeV region, can have Black Hole
production!!
Status: Not seen yet, maybe around the corner. . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Extra Dimensions
Particle physics is confined
to a brane and interacts
with extra dimensions and
other ’hidden dimensions’
through gravitons.
(Randall Sundram
scenario) In the ADD
scenario, one can have
graviton production which
manifests itself as missing
energy.
If Planck scale comes down to the TeV region, can have Black Hole
production!!
Status: Not seen yet, maybe around the corner. . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Extra Dimensions
Particle physics is confined
to a brane and interacts
with extra dimensions and
other ’hidden dimensions’
through gravitons.
(Randall Sundram
scenario) In the ADD
scenario, one can have
graviton production which
manifests itself as missing
energy.
If Planck scale comes down to the TeV region, can have Black Hole
production!!
Status: Not seen yet, maybe around the corner. . .
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
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 for
theorists and experimentalists. Status: Not seen yet...
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
Summary
LHC expected to start “very soon” - at 5 TeV
With a factor of 7 jump in energy from present day accelerators, the
LHC will (hopefully) provide us a whole new world of TeV physics.
Hunt for new physics – but very challenging to unravel different
signatures 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 make
sense of the enormous amount of data that will be produced
The Large Hadron Collider
The Structure of Matter
The Four Forces
Final Picture
The LHC
Theory Issues
No better time to get into High Energy Physics