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arXiv · 1407.0141

Small scale structures in coupled scalar field dark matter

Joschka Beyer·Christof Wetterich
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Abstract

We investigate structure formation for ultralight scalar field dark matter coupled to quintessence, in particular the cosmon-bolon system. The linear power spectrum is computed by a numerical solution of the coupled field equations. We infer the substructure abundance within a Milky Way-like halo. Estimates of dark halo abundances from recent galaxy surveys imply a lower bound on the bolon mass of about $9 \times 10^{-22}$ eV. This seems to exclude a possible detection of scalar field dark matter through time variation in pulsar timing signals in the near future.

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Joschka Beyer, Christof Wetterich. 2014-07-01. Small scale structures in coupled scalar field dark matter. https://doi.org/10.1016/j.physletb.2014.10.012

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