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arXiv · 1408.4893

A unified solution to the small scale problems of the $Λ$CDM model II: introducing parent-satellite interaction

Antonino Del Popolo·Morgan Le Delliou
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Abstract

We continue the study of the impact of baryon physics on the small scale problems of the $Λ$CDM model, based on a semi-analytical model (Del Popolo, 2009). Withsuch model, we show how the cusp/core, missing satellite (MSP), Too Big to Fail (TBTF) problems and the angular momentum catastrophe can be reconciled with observations, adding parent-satellite interaction. Such interaction between darkmatter (DM) and baryons through dynamical friction (DF) can sufficiently flattenthe inner cusp of the density profiles to solve the cusp/core problem. Combining, in our model, a Zolotov et al. (2012)-like correction, similarly to Brooks et al. (2013), and effects of UV heating and tidal stripping, the number of massive, luminous satellites, as seen in the Via Lactea 2 (VL2) subhaloes,is in agreement with the numbers observed in the MW, thus resolving the MSP and TBTF problems. The model also produces a distribution of the angular spin parameter and angular momentum in agreement with observations of the dwarfs studied by van den Bosch, Burkert, \\& Swaters (2001).

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Antonino Del Popolo, Morgan Le Delliou. 2014-11-21. A unified solution to the small scale problems of the $Λ$CDM model II: introducing parent-satellite interaction. https://doi.org/10.1088/1475-7516%2F2014%2F12%2F051

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