Branon Dark Matter

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Introduction brane fluctuations

• - Rigid branes ( f gtgt
  MD)
• KK modes
• Brane-world
• scenario
• (ADD, 98) - Flexible branes
  (f ltlt MD)
• Branon fields
• (KK modes
  decouple from SM)
• Bando et al. 99

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Brane fluctuations

• Bulk metric
• Brane position
• Branon fields
• Branon mass related to bulk curvature

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Branon dynamics

• Induced metric on the brane
• Dirac-Nambu-Goto action
  
• Branon effective action Sundrum
  99, Dobado A.L.M 01

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Limits from colliders

• Induced metric on the brane
• Dirac - Nambu - Goto action
  
• Branon action

LEP-II ...
TEVATRON-I
...
hep-ex/0407017

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A new dark matter candidate

• Brane orientation branons are
  pseudoscalar particles
• Parity on the brane branons
  couple by pairs to SM
  
  .
  (stable particles)
• Branons are stable, massive and weakly
  interacting particles
• NATURAL DARK MATTER CANDIDATES
  

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Branon cosmic abundance
Freeze-out in an expanding universe Annihila
tion into all SM pairs X
, e.g. annihilation into
photons,
Cold branons (M gtgt T) Hot
branons (M ltlt T)
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Branon cosmic abundance
Cold branons WMAP limits
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Branon cosmic abundance
Hot branons
WMAP
WMAP-CBI-ACBAR-2dF-Ly-a
BBN limits for
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Combined limits
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Direct detection
Elastic branon-nucleon

cross section

(spin independent)
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Non-thermal branon production
If TRHltlt Tf and TRH gtgt L (L explicit
symmetry breaking scale). Branons are essentially
massless and decoupled from SM. Brane initial
position Y0 O (RB) and p0 f 2 RB Dark
matter as coherent brane oscillations (similar to
axions) If H(T) gt G(T) for T lt TRH brane
oscillations only diluted by Hubble expansion.
Non-thermal branon abundance
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Cosmic coincidence problem
AdS6 soliton solution Branon
mass Fundamental scale
Bulk C.C. (loop
effects)
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Conclusions and future perspectives

• Branons are natural dark matter candidates in
  brane-world
• models.
• Produced as thermal or non-thermal relics
  (cosmic coincidence)
• ... or strongly self-interacting dark matter.
• They could be detected in future direct search
  experiments (CDMS, CRESST II, ...).
• Indirect detection from halo annihilations into
  photons or ee- by MAGIC, GLAST or AMS (coll.).
• Indirect detection by ANTARES, IceCube, ...
  from annihilation into high-energy neutrinos.
• L3 coll. direct searches (published results)
• Future searches at hadronic (LHC) or Linear
  Colliders.