The ATLAS Experiment the ultimate Emc2

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The ATLAS Experiment the ultimate Emc2
Chris Oram
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Outline

• Einstein Emc2 , the ether
• Using Emc2 Making and annihilating particles
• Making very massive particles the LHC
• The ATLAS experiment
• Watching particles collide
• Why watch particles collide ?
• High School Physics Books 1905-2005
• What we do not understand
• What to expect how to think!

Some technical how to slides
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Einstein

• Emc2 is the famous equation BUT what Einstein
  really did, was to say
• The speed of light is a constant
• A trivial but far reaching statement !

Vgalaxy 2.2 x 105 m/s Vsun 5 x 103 m/s
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Einstein continued

• It meant there was NO ether
• What was this ether ???
• Well it was a theoretical postulate

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The Ether
Einstein on Ether http//www.tu-harburg.de/rzt/rz
t/it/Ether.html

• Light is a wave waves move in a medium
• How come we see action at a distance?
• (gravity magnets)
• ?
• Postulate Ether

Theory
Postulated Measurable Speed of light variation
? Result of measurement NO variation
Experiment
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Einstien

• Destroyed the Ether Theory
• Stated the speed of light is a constant
• Many many more things and
• Emc2

The ATLAS experiment 100 years later uses
Emc2 BUT seeks to explain mass (the m) by the
vacuum. The Vacuum and The Ether are rather
similar!
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More on Emc2

• Two Light beams (photons) strike each other head
  on
• Each has energy E (and no mass)

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More on Emc2

• Form 2 particles. If each has no momentum then
• m E / c 2

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More on E m c 2

• Energy can be switched into Mass
• AND
• Mass switched into Energy

Physicists do both routinely
m
Time Reversal Invariance
m
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More on Emc2

• If you want to make a BIG mass you need a BIG
  energy
• Ebig mbig c 2

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BIG Energies

• ATLAS has two proton beams each with
• 7 TeV T1012

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Getting 7 x 1012 Volts
28 Kilometre Circumference tunnel
One 600,000 Volt Kick on each rotation 1.2 x 107
Rotations (600,000 V x 1.2 x 107 7 x 10 12
V) Moving at c 3 x 108 m/sec 28,000 m
takes 9 x 10-5 sec 1.2 x 107 rotations take 103
sec 20 mins
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Stored Energy

• 0.6 amps at 7 TeV Aircraft Carrier at 30 Knots

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Keeping 7 TeV particles going in a circle

• Requires VERY powerful magnets 28 km worth!
• CERN engineers had to increase the maximum field
  of a mass production super-conducting magnets

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The 28Km LHC Tunnel
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Inside the 28Km LHC Tunnel
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LHC two counter rotating beams collide at 4
locations!
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The ATLAS Experiment
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The ATLAS Experiment big by any measure

• 7000 Tonnes
• 1800 Scientists
• 15 years to build
• 35 Countries
• 500M in materials

What does it do?
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Observes collisions

• But this collision is so small you cannot see
  it so you measure all the particles that come out

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Observes collisions
Measure Direction, Momentum, Energy Of every
particle
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Measure Direction

• Pixel detector has nearly 80 million channels!
• Each Pixel wafer measures 16x60mm and has 46,000
  pixels 50x400 microns

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Measure Momentum

• Inner detector in 2 Tesla magnetic field 20000
  Gauss

100 Gauss
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Measure Energy
3 metres of Metal
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Observes collisions

• Summing the energies of sets of tracks you
  measure the masses of particles that exploded
  and look for new particles

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Actual Collisions can be very complicated

• Need lots of computing power
• 8 Pbytes data per year. (G-109, T-1012, P-1015)
  8 km stack of CDs without jewel cases!

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The GRID a world wide web of computers

• The World Wide Web was invented by particle
  physicists in order to share data more easily and
  it ended up changing the way the world uses and
  exchanges information.
• The Grid is the next step and promises to change
  the way we process information and create new
  knowledge.

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Why do this ???

• We believe we are on the breaking point of our
  present theories we await a new Einstein
• Meanwhile we make measurements to try and find
  differences between our present theories
  predictions and reality!
• Going to the highest energies and directly
  observing new particles has historically been a
  good approach (upcoming slides).

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Breaking Point WHY?

• The present theory has 20 free parameters, and
  is rather complicated
• Rather like the periodic table of the elements
  before we knew elements were made of a nucleus of
  Neutrons and Protons with electrons orbiting
• Rather like when Einstein gave us Emc2 100
  years ago

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The development from large to small
Neutron Stars and nuclei are (105)3 more dense
than water. Chemistry is all about electrons!
To see small things you need high energies !
(Quantum Mechanics)
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ATLAS
TRIUMF
The Sun
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100 Years AGO Canadian High School Text
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100 Years AGO Canadian High School Text (
Published 1902)

• Much on the Last page was WRONG (However
  Maxwells Theory remains accepted today.)
• Published before Einstein wrote his papers in
  1905!
• Einstein was taught this at high school!

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Your 2005 High School Text which page is wrong?
The last page is interesting like in 1902 it
deals with the important issues of the day! I
suspect it is in these important issues (and
assumptions) the key to the new theory lies.
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What did they not understand in 1902 ?

• Action at a distance
• Why the speed of light always measured the same
  independent of the speed of the source relative
  to the observer
• The black body spectrum
• The stability of the atom
• and a few other problems
• Out of explaining the above came
• Quantum Mechanics
• Relativity
• Modern Physics
• It changed the way we view the world !

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What do we not understand ?

• Mass
• Quantum Mechanics and Gravity
• Dark Matter (gravity at large distances)
• Dark Energy (expanding universe)
• Why do some particles have charge 1 and others
  charge 1/3rd 2/3rds
• Why are our theories so complicated?
• Matter Anti-Matter asymmetry in universe
• Understanding this will change the way we view
  the world

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The Standard Model of Particle Physics

• 6 Quarks (and 6 Anti-Quarks) 6 Leptons (and 6
  Anti-Leptons)
• 3 Connecting Particles the quark glue
• Photon, W, Z gluons in 3 colours
• Gravity
• Gravitino
• The Higgs

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20 Parameters (minimum)

• 6 Quark Masses (6)
• 6 Lepton Masses (12)
• Z W Masses (14)
• Gluon Coupling (15)
• W Z Coupling (16)
• Photon Coupling (17)
• Inter-Generation Coupling (Cabibbo) (18)
• Gravity Coupling (19)
• Higgs Mass (not yet measured) (20)

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The Higgs

• To understand the Higgs mechanism, imagine that a
  room full of politicians chattering quietly is
  like space filled with the Higgs field ...

A quasi-political Explanation of the Higgs Boson
for Mr Waldegrave, UK Science Minister 1993. When
CERN was trying to get funding for the LHC
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The Higgs

• A well-known politician walks in, creating a
  disturbance as she moves across the room and
  attracting a cluster of admirers with each step

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The Higgs

• This increases her resistance to movement, in
  other words, she acquires mass, just like a
  particle moving through the Higgs field...

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The Higgs

• If a rumor crosses the room, ...

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The Higgs

• It creates the same kind of clustering, but this
  time among the politicians themselves. In this
  analogy, these clusters are the Higgs particles.

Today on the ATLAS web page http//atlasexperimen
t.org the politician is replaced by a physicist !
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1905 to 2005

• The combination of measurements of the very big
  and the very small is the challenge to our
  theories
• Very Big radius of the universe
• 10 billion light years 1025 metres
• Very Small wavelength of highest energy
  particle
• 1TeV 2 10-19 metres
• In my opinion the study of astronomy and particle
  physics are the studies of the frontiers of
  knowledge and thus particularly worth studying

1044
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Conclusion

• I think we live in interesting times
• I think you will see a revolution in Science in
  your lifetime the effects will reach far beyond
  science
• I believe that measurements of the very big
  (astronomy), and the very small (particle
  physics) are essential to speeding the start of
  this revolution
• It is likely the revolution in Science will be
  in a very unexpected area, where the dogma is
  strongest today !

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Think outside the box !
Look out for Scientific Dogma Einstein was
taught incorrect physics at School !
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