Seminario de Astrofísica en el IFIS. Este martes 6 de mayo, Constanza Soto estudiante de Doctorado de Ciencias Físicas de la PUCV y UTFSM, presenta “Bias Function and the Cosmic-Web connection” desde las 14:30 en la Sala 208 del Instituto de Física PUCV.

Revisa el abstract de la presentación:

The spatial distribution of galaxies and dark matter haloes is not random and carries crucial information about the evolution of the universe. When referring to large-scale structure (LSS), we describe an inhomogeneous universe whose nature is studied through the evolution of perturbations in the density field. On larger scales, the evolution of these fluctuations, driven by the gravitational interaction of matter, gives rise to the formation of complex structures such as nodes, filaments, voids, and walls, collectively known as the cosmic web. Following this idea, the relation between the distribution of galaxies or dark matter haloes and the underlying matter density field is referred to as bias. The primary dependence of halo clustering is on halo mass, such that more massive haloes are more clustered than their less massive counterparts. However, secondary properties, at fixed halo mass, also influence clustering, leading to the so-called secondary bias. In this study, using the TNG300 hydrodynamical simulation, we employed an individual halo bias estimator, leveraging its advantages over traditional methods. With this estimator, we constructed the halo bias function, defined as the relation between the average individual bias per halo mass bin. By analyzing the halo bias function across different environments, we found that the trend varies for each environment, indicating that haloes located in the outskirts of nodes are highly clustered, in contrast to haloes in voids and walls. Similarly, linking to galaxy properties, we observed that haloes hosting red galaxies are more clustered, across all environments, than those hosting blue galaxies. Additionally, at low masses (log10(Mhost) < 12.5 h−1M⊙), red galaxies are significantly influenced by nearby massive haloes (log10(Mhost) > 13.5h−1M⊙)) within a radius of 5 h−1Mpc.