Conveners
Halo Theory: profile formation
- Neal Dalal (Perimeter Institute for Theoretical Physics)
Halo Theory: profile formation
- Neal Dalal (Perimeter Institute for Theoretical Physics)
The self-similar spherical collapse model provides an insightful framework for understanding the formation and evolution of galaxy clusters in an expanding Universe. However, cosmological simulations have revealed significant deviations of the cluster outskirts and their evolution from the self-similar prediction. In this talk, I will discuss intriguing physics behind this problem and...
The inner regions of dark matter halos exhibit a rich dynamical structure shaped by multi-streaming and phase-space mixing. In this talk, I will present our recent investigations into the multi-streaming region, characterized by the number of apocenter passages or the radial action of dark matter particles. Our results reveal a remarkable universality: when categorized by their number of...
Dark matter halos are self-gravitating objects seeded from small density perturbations in the early universe. Their structure can be described by a universal spherical averaged density profile across the scale of nearly all astronomical objects - the NFW profile - whose physical origin is not well understood. In recent N-body simulations, halos forming density profile as power-law with index...
Scaling relations between dark matter halos provide profound insights into dark matter properties, revealing empirical correlations across cosmic structures. Many studies suggest that the mass surface density of dark matter halos remains remarkably constant over a wide range of total masses (Burkert 1995; Spano et al. 2008; Donato et al. 2009; Salucci et al. 2012; Kormendy & Freeman 2016;...
I will present our work on measuring the Milky Way (MW)’s halo edges and modeling the tidal stripping of satellite galaxies, addressing two key aspects of halo dynamics and boundaries: (1) halo growth and (2) environmental effects, respectively.
(1) Using the kinematics of nearby dwarf galaxies within 3 Mpc, we measured the depletion radius and the turnaround radius of the MW, along with...
The size and density profiles of dark matter (DM) halos have been extensively studied in simulations and observations. In simulations, DM halo properties are `universal' and can be scaled appropriately. However, unlike simulations, determining the sizes from observations has been limited to larger mass halos. For example, the splashback radius is now measured in cluster-sized halos, and...
