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Dark Matter Minihalos from Primordial Magnetic Fields
1SISSA, International School for Advanced Studies, via Bonomea 265, 34136 Trieste, Italy.
Physical Review Letters
|December 22, 2023
Summary
Primordial magnetic fields (PMFs) can seed dark matter minihalos. Turbulent damping affects baryons, but dark matter perturbations grow, forming minihalos potentially detectable via blazar observations.
Area of Science:
- Cosmology
- Astrophysics
- Particle Physics
Background:
- Primordial magnetic fields (PMFs) influence early universe perturbations.
- Baryon perturbations are enhanced by PMFs but damped by turbulence near recombination.
Purpose of the Study:
- To investigate the formation of dark matter minihalos from PMF-induced baryon perturbations.
- To explore the potential link between blazar-observed magnetic fields and minihalo formation.
Main Methods:
- Analyzing the gravitational influence of baryon perturbations on dark matter.
- Modeling turbulence effects on baryon fluids near recombination.
- Considering PMFs with a Batchelor spectrum.
Main Results:
- Gravitational growth of dark matter perturbations, unaffected by baryon turbulence.
- Formation of 10^{-11}-10^{3}M_{⊙} dark matter minihalos.
- PMFs with a Batchelor spectrum could generate these minihalos.
Conclusions:
- PMFs can be a viable source for dark matter minihalo formation.
- Blazar observations might provide evidence for such PMFs and minihalos.
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