We study the halo mass accretion history (MAH) and its correlation with the internal structural properties in coupled dark energy (cDE) cosmologies. To accurately predict all the non-linear effects caused by dark interactions, we use the COupled Dark Energy Cosmological Simulations (CoDECS). We measure the halo concentration at z = 0 and the number of substructures above a mass resolution threshold for each halo. Tracing the halo merging history trees back in time, following the mass of the main halo, we develop a MAH model that accurately reproduces the halo growth in term of M200 in the λcold dark matter (λCDM) Universe; we then compare the MAH in different cosmological scenarios. For cDE models with a weak constant coupling, our MAH model can reproduce the simulation results, within 10 per cent of accuracy, by suitably rescaling the normalization of the linear matter power spectrum at z = 0, σ8. However, this is not the case for more complex scenarios, like the 'bouncing cDE model, for which the numerical analysis shows a rapid growth of haloes at high redshifts, that cannot be reproduced by simply rescaling the value of σ8. Moreover, at a fixed value of σ8, CDM haloes in these cDE scenarios tend to be more concentrated and have a larger amount of substructures with respect to λCDM predictions. Finally, we present an accurate model that relates the halo concentration to the time at which it assembles half or 4 per cent of its mass. Combining this with our MAH model, we show how halo concentrations change while varying only σ8 in a λCDM Universe, at a fixed halo mass.
Titolo: | Characterizing dark interactions with the halo mass accretion history and structural properties | |
Autore/i: | GIOCOLI, CARLO; MARULLI, FEDERICO; BALDI, MARCO; MOSCARDINI, LAURO; METCALF, ROBERT BENTON | |
Autore/i Unibo: | ||
Anno: | 2013 | |
Rivista: | ||
Digital Object Identifier (DOI): | http://dx.doi.org/10.1093/mnras/stt1218 | |
Abstract: | We study the halo mass accretion history (MAH) and its correlation with the internal structural properties in coupled dark energy (cDE) cosmologies. To accurately predict all the non-linear effects caused by dark interactions, we use the COupled Dark Energy Cosmological Simulations (CoDECS). We measure the halo concentration at z = 0 and the number of substructures above a mass resolution threshold for each halo. Tracing the halo merging history trees back in time, following the mass of the main halo, we develop a MAH model that accurately reproduces the halo growth in term of M200 in the λcold dark matter (λCDM) Universe; we then compare the MAH in different cosmological scenarios. For cDE models with a weak constant coupling, our MAH model can reproduce the simulation results, within 10 per cent of accuracy, by suitably rescaling the normalization of the linear matter power spectrum at z = 0, σ8. However, this is not the case for more complex scenarios, like the 'bouncing cDE model, for which the numerical analysis shows a rapid growth of haloes at high redshifts, that cannot be reproduced by simply rescaling the value of σ8. Moreover, at a fixed value of σ8, CDM haloes in these cDE scenarios tend to be more concentrated and have a larger amount of substructures with respect to λCDM predictions. Finally, we present an accurate model that relates the halo concentration to the time at which it assembles half or 4 per cent of its mass. Combining this with our MAH model, we show how halo concentrations change while varying only σ8 in a λCDM Universe, at a fixed halo mass. | |
Data prodotto definitivo in UGOV: | 2014-03-03 13:21:21 | |
Appare nelle tipologie: | 1.01 Articolo in rivista |