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

Antonino del Popolo (1, 2) , Morgan Le Delliou (3)

1 Dipartimento di Fisica e Astronomia [Catania]
2 IIP-UFRN - International Institute of Physics, Universidade Federal do Rio Grande do Norte
3 IFT-UNESP - Instituto de Fisica Teorica

We continue the study of the impact of baryon physics on the small scale problems of the $\Lambda$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).

Mots clés: cosmology: theory; large scale structure of universe; galaxies: formation

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Cosmologie et astrophysique extra-galactique [astro-ph.CO]

Antonino del Popolo, Morgan Le Delliou. A unified solution to the small scale problems of the $\Lambda$CDM model II: introducing parent-satellite interaction. 2014. ⟨hal-01056904v2⟩