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THE SCALAR FIELD DARK MATTER MODEL It is an alternative model to CDM SFDM model is insensitive to initial conditions Behaves as CDM at cosmological scales Reproduces all the successes CDM above galactic scales. Predicts a sharp cut-off in the mass power spectrum The favored values for the two free parameters 20 V0 (310-27 Mpl )4 m 10-23 eV
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Oscillatons as Galactic Dark Matter Halos
Tonatiuh Matoshttp:/www.fis.cinvestav.mx/~tmatos
• Inflation• +• Scalar Field DM
(SFDM)• +• Dark Energy
Cosmology +Galaxies Formation
=
• The model consists of
THE SCALAR FIELD DARK MATTER MODEL
• It is an alternative model to CDM• SFDM model is insensitive to initial conditions • Behaves as CDM at cosmological scales• Reproduces all the successes CDM above
galactic scales.• Predicts a sharp cut-off in the mass power
spectrum • The favored values for the two free parameters 20 V0 (310-27 Mpl )4 m 10-23 eV
The Model comes from• Examples:• Braneword Scenario• Superstrings • contain effective SF potentials:• V f1exp() + f2exp(-) + …• • V = V0[cosh() – 1]
• If• H2 = 8/(3Mpl
2) (1 + /b)• Inflation graceful exit• BBN Cosmology • Fix the free constants. • James Lidsey, Tonatiuh Matos and Luis A.
Ureña. PhysRevD66(2002)023514.
The CosmologyT. Matos and L. Ureña, Class. Q. Grav. 17(2000)L75
• SFDM with the SF potential:• V = V0[cosh() –1]• Dark Energy:
• +
• Baryons, Neutrinos, etc.
0.23 0.73b 0.04
Scalar Field Fluctuations
T. Matos and L. Ureña, Phys. Rev. D63(2001)063506
The linear fluctuations of the SFDM model follow the
CDM ones
Natural Cut-off
The linear fluctuations contain a natural cut-of in the mass power spectrum. Thus, this model has no problems with
the production of substructure.
Scalar Field Fluctuation = Oscillaton = Galaxy Halo
Tonatiuh Matos and F. Siddhartha Guzman Class. Q. Grav. 17(2000)L9; T. Matos, F. S. Guzman and D. Nuñez, Phys. Rev. D62(2000)061301(R);Tonatiuh Matos and F. Siddhartha Guzman, Class.Q. Grav. 18(2001)5055
The critical mass of oscillatons collapse is
• Mcrit 0.1 M2Planck /m
• If m 10-23 eV 20
• Mcrit 1012 M¯ ~ Galaxy halo
Galaxy virialization
• The oscillatons virialize in a very short time. In this figure it is shown the rate of kinetic energy K and potential energy |W| of the scalar field fluctuation. It goes very fast to ½.
Density Profiles
Here we show the comparison between the NFW, Isothemal and the SFDM density
profiles for galaxies.
Density Profiles
Density Profiles
LSB Galaxies
Density Profiles
LSB Galaxies
Conclusion
• The scalar field is a good candidate to be the Dark Matter
of the Universe