Speaker
Description
The halo model is a powerful tool for understanding the non-linear evolution of the large-scale structure. Conventionally, a dark matter halo is defined as a collapsed object in virial equilibrium, with its boundary set by the virial radius. However, this definition does not appropriately separate the halo and the environment, as a halo is much more extended beyond the virial radius and grows continuously. Consequently, the classical halo model fails in the transition region between the halo edge and the large-scale environment. A better understanding of the halo boundary and a more accurate and explicit halo model are needed in future cosmological analyses.
In this talk, I will present an improved halo model that based on a new characterization of the halo boundary called depletion radius. By selecting halos with new boundary definition, we find that the model ingredients (halo mass function, halo profile, and halo-halo correlation) can be expressed simply and naturally (arXiv: 2303.10886). Coupling all the ingredients our model accurately predicts the multiple statistics of the halo and matter field without ad hoc fixes (arXiv: 2407.08381). I will show the latest progress of our model across a wide cosmological parameter space, and demonstrate the potential applications of our model in cosmological analyses. finally I will compare our model to other existing halo models (e.g., HALOFIT and HMCODE), and highlight the advantages of our model in terms of clarity, interpretability, and versatility.
