N-body simulations with a cosmic vector for dark energy

Understand

We present the results of a series of cosmological $N$-body simulations of a Vector Dark Energy (VDE) model, performed using a suitably modified version of the publicly available \texttt{GADGET}-2 code.

• The setups of our simulations were calibrated pursuing a twofold aim: 1) to analyze the large scale distribution of massive objects and 2) to determine the properties of halo structure in this different ramework.We observe that structure formation is enhanced in VDE, since the mass function at high redshift is boosted up to a factor of ten with respect to \LCDM, possibly alleviating tensions with the observations of massive clusters at high redshifts and early reionization epoch.
• Significant differences can also be found for the value of the growth factor, that in VDE shows a completely different behaviour, and in the distribution of voids, which in this cosmology are on average smaller and less abundant.
• We further studied the structure of dark matter haloes more massive than $5\times10^{13}$\hMsun, finding that no substantial difference emerges when comparing spin parameter, shape, triaxiality and profiles of structures evolved under different cosmological pictures.