The Asymmetry between Matter and Antimatter

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The Asymmetry between Matter and Antimatter

• Besma Mcharek
• FEW, Vrije Universiteit Amsterdam

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Matter
Matter/antiMatter
quarks
electron
Nucleus
neutron proton
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Matter and anti-Matter
E mc2
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The Standard Model the building blocks

• The fundamental building block of matter consists
  of 6 quarks (u, d, c, s, t, b)
• 6 leptons (e,µ,t,?e,?µ,?t).

• Each of those building blocks has a corresponding
  anti-building block.

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The Standard Model Forces in nature

• The particles interact through four different
  forces
• electromagnetic
• gravity
• weak forces
• strong forces

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Where is the antimatter?
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Where is the antimatter?
13.7 billion y
1 billion y
300,000 y
300 s
10?6 s
10?11 s
lt 10?11 s
3000K
life
1st stars
H/He
matter antimatter
EM
EW
hadrons
nucleus
atom
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How We Go From a Particle to an Anti_particle?

• Two steps
• Parity conjugation (P)
• Charge conjugation (C)
• Only the weak force, to some extent,
  distinguishes between the particles and the
  antiparticles

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Escher and Weak forces
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CERN
? 8.8 km
Alice
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The LHCb detector
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Summary

• In the universe, there is an asymmetry (small
  difference) between matter and antimatter.
• We need to learn more about the weak force in
  order to explain this asymmetry.
• We will use the LHCb detector at CERN where we
  can create the proper conditions.
• The measurements will start in 2007, however a
  lot of work needs to be done before.