Who is Your Daddy and What Does He Do The Search for Cold Dark Matter Axions

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Who is Your Daddy and What Does He Do?The
Search for Cold Dark Matter Axions

• Glenn Howe
• 4/25/07

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Agenda

• Intro to CP Symmetry
• The CP Problem
• Classical Analogy
• Quantitative Analysis
• Final Remarks

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Agenda

• Intro to CP Symmetry
• -Particle Physics
• -Charge/Parity
• The CP Problem
• Classical Analogy
• Quantitative Analysis
• Final Remarks

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Agenda

• Intro to CP Symmetry
• The CP Problem
• -Quantum Chromodynamics (QCD)
• -Possible Solution ? Axions
• Classical Analogy
• Quantitative Analysis
• Final Remarks

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Agenda

• Intro to CP Symmetry
• The CP Problem
• Classical Analogy
• - Snooker (Billiards)
• Quantitative Analysis
• Final Remarks

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Agenda

• Intro to CP Symmetry
• The CP Problem
• Classical Analogy
• Quantitative Analysis
• -Mass Limits
• -Detecting Axions
• Final Remarks

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Agenda

• Intro to CP Symmetry
• The CP Problem
• Classical Analogy
• Quantitative Analysis
• Final Remarks
• -Impact on Dark Matter

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CP Symmetry

• C Charge Conjugation
• Electron/positron
• Neutrino/antineutrino
• P Parity
• (x,y,z) ? (-x,-y,-z)
• CP Symmetry was thought to be fundamental

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CP Symmetry

• 1964 CP broken in weak interactions
• 2001 CP broken using B mesons
• Widely accepted that CP can be broken except
• QCD does not show violation of CP Symmetry

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CP Problem

• Why doesnt QCD violate CP Symmetry? (strong
  interactions)
• dn 5 x 10-16?
• Experimentally, dn lt 10-25
• ? lt 10-10 (Early Universe?)
• Why is this?

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Peccei-Quinn Theory

• Instead of having ? be a constant, treat it as a
  dynamic (changing) field.
• Quantum Field theory Fields are associated with
  their own particles.
• EM photons
• Weak W and Z bosons
• Strong gluons
• Gravity gravitons?
• There must be some new particle! Axion

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Classical Analogy of Snooker (Pierre Sikivie)
Need symmetry, S (Analog of CP Symmetry) Discover
symmetry is not universal, but table is still
horizontal (CP violated?) Tilt of pool table, ?
lt 10-10 How was it built?
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Classical Analogy of Snooker (Pierre Sikivie)
Automatically adjusts under gravity (PQ solution
to CP problem) ? is now a dynamic variable (PQ
mechanism pulls ? to zero, axion is
oscillation) This accounts for the lack of CP
violation Could this be how the table is made?
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Classical Analogy of Snooker (Pierre Sikivie)
Double check pool table physics Oscillations
depend on length of lever arm (decay const. f
mc2 h?) Length gt 3m (cannot produce
oscillations)
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Classical Analogy of Snooker (Pierre Sikivie)
Snooker is played on Mars, table is made in
U.S.A. How did it travel, slow down, and land?
(measure relic oscillations) Larger L ?low
frequency ? more sudden stop Suddenness of stop ?
turn on of QDC (t10-7 s) Length lt 10m (no
relic oscillations)
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Quick Recap

• There is something weird with ?
• Treat it as dynamic variable
• Some mechanism pulls ? to zero
• Check for induced and relic oscillations

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Quantitative Analysis

• Mass has limits due to f (much like length had
  limits)
• Allowed mass range 1 µeVlt ma lt 10meV ( e-
  .511 MeV)
• ma 10-5 eV (very light and weakly coupled)
• ma 1.78 x 10-41 kg
• If only source of dark matter
• Number 1.0 x 1082 axions in our solar radius
• Number density 4.47 x 1069 axions/pc3
• 4.7 x 1065 per second through our solar system
• 2.67 x 1036 per second through your pinky
  fingernail

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Quantitative Analysis

• This is 2.67 undecillion axions
• or
• 2,670,000,000,000,000,000,000,000,000,000,000,000
• Axions per second through your pinky fingernail

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Detection??

• Axions thought to break into two photons under
  large magnetic fields.
• Axion Dark Axion Dark-Matter Experiment (ADMX)
  2006
• To date, all candidates have either disappeared
  upon re-scanning or have been linked to external
  interference
• Other experiments met with similar results
• Future searches may have better luck?

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Final Remarks

• We shouldnt jump to conclusions

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Some sources

• L. D. Duffy et al., A High Resolution Search for
  Dark-Matter Axions, Phys. Rev. D 74, 012006
  (2006)
• R. D. Peccei, H. R. Quinn, Physical Review
  Letters, 38(1977) p. 1440.
• http//www.phys.ufl.edu/axion/pooltable_sikivie.p
  df
• http//faculty.washington.edu/sethh/mongolia_axion
  .pdf
• http//web.mit.edu/redingtn/www/netadv/specr/345/
  node3.html
• http//neutrinosantafe06.com/downloads/Session11/1
  1.5Kinion.pdf
• Kindergarten Cop
• Homeless guy that wanders around UMass
• www.ebay.com