MATs (Monday Afternoon Talks), 5/13/2024 — Speakers: Elia Pizzati & Elena Hernandez

Monday May 13, 2024 3:00 pm

MATs (Monday Afternoon Talks)

3:00pm – 3:30pm, Elia Pizzati
Tracing the rapid evolution of supermassive black holes with High-z Quasar Clustering measurements
Quasar clustering measurements have always been a fundamental ingredient on which we built our understanding of supermassive black holes, their accretion mechanisms, and the co-evolution with their host galaxies/halos. Recently, ground-breaking progress has been made in extending these studies to the high-z Universe: using JWST NIRCam-WFSS observations, the EIGER team has measured for the first time the quasar-galaxy cross-correlation function at z>6. This measurement is nicely complemented by the recent determination of the large-scale quasar auto-correlation function at the same redshift. Together, these early data suggest that high-z quasars live in moderately strong overdensities, with a large correlation length that agrees well with the trend observed at z~2-4.
In this work, we use these new data to build a model jointly describing the properties of quasars and galaxies at high redshift. We do that by running a new, large-volume cosmological simulation with more than a trillion particles, which contains halos whose abundance spans more than seven orders of magnitude. Complementing the simulation with an empirical quasar/galaxy population model, we successfully reproduce observations and infer key properties of quasars and galaxies, such as their host mass distributions and duty cycles, that are directly related to the growth of supermassive black holes and the coevolution between them and their hosting galaxies. By comparing the results of our model at different redshifts, we study how quasar activity evolves rapidly across cosmic time. Finally, we discuss the implications of our findings, also in light of the recent discovery of an extremely abundant population of faint and/or obscured AGN in JWST surveys.

3:30pm – 4:00pm, Elena Hernandez
Simulating our universe: how and why?
We will present SLOW, the simulated cosmic volume (500 Mpc/h) that features the most extensive collection of Local Universe Galaxy Clusters ever replicated, accurately set within the appropriate large-scale framework. We will show current predictions about these structures based on our simulated results and compare them with observational data. Additionally, the discussion will cover how these simulations open new avenues for research in galaxy cluster and cosmology studies.

Hosts: Minghao Yue, Daniele Michilli


  • Elia Pizzati, Leiden
  • Elena Hernandez, CCA