El próximo martes 24 de junio, a las 14:30 horas, Javier Urrutia, máster en Física PUCV, dictará el seminario “Joint Constraints on the Richness–Mass Scaling Relationship and Electron Pressure Profiles of Galaxy Clusters” en la Sala 208 del Instituto de Física, Campus Curauma, PUCV.
Compartimos el resumen de la presentación:
Galaxy clusters are one of the most important cosmological probes in the Universe. These correspond to the largest and most massive gravitationally bound objects and they give rise to a variety of gravitational and non-gravitational phenomena. One of the most important property of clusters is their mass, which is highly useful in cosmology. Unfortunately, most of the clusters’ matter content is dark matter. Therefore, it is useful to calibrate cluster mass using other relatively accessible properties. These relationships are called scaling relations. The richness-mass relationship is a well-known example of these with low scatter, which relates the total mass content of a cluster with how many red galaxies it contains.
On the other hand, the baryonic content in galaxy clusters, mainly located in the Intra-Cluster Medium (ICM), provides additional information. Unfortunately, baryons can be affected by non-gravitational physical processes. One powerful way of studying the ICM is the Thermal Sunyaev-Zel’dovich Effect, a spectral distortion induced in the Cosmic Microwave Background (CMB) produced by inverse Compton scattering between photons in the latter and electrons in the ICM. CMB photons can be also deflected by the presence of mass, an effect called CMB lensing. This means that combining both distortions makes it possible to access simultaneously the thermodynamical and gravitational state of clusters.
On this talk, we present a new richness-mass relationship, and a universal mass and electron pressure profile obtained by combining the latest data release from the Atacama Cosmology Telescope (ACT), which provides CMB Comptonization and lensing maps, with a cluster catalog obtained by applying the RedMaPPer algorithm to Dark Energy Survey (DES) Y3 data. This results are not only going to provide a new celibration but also will shed light on the radial distribution of hot gas and dark matter in a large cluster sample as a function of richness and redshift.
Extendemos la invitación a la comunidad del Instituto de Física y al público interesado a participar de este seminario.
