On the Cosmic Web Elongation in Fuzzy Dark Matter Cosmologies: Effects on Density Profiles, Shapes and Alignments of Halos

Understand

The fuzzy dark matter (FDM) scenario has received increased attention in recent years due to the small-scale challenges of the vanilla Lambda cold dark matter ($\Lambda$CDM) cosmological model and the lack of any experimental evidence for any candidate particle.

• In this study, we use cosmological $N$-body simulations to investigate high-redshift dark matter halos and their responsiveness to an FDM-like power spectrum cutoff on small scales in the primordial density perturbations.
• We study halo density profiles, shapes and alignments in FDM-like cosmologies (the latter two for the first time) by providing fits and quantifying departures from $\Lambda$CDM as a function of the particle mass $m$.
• Compared to $\Lambda$CDM, the concentrations of FDM-like halos are lower, peaking at an $m$-dependent halo mass and thus breaking the approximate universality of density profiles in $\Lambda$CDM.