Letters of Intent received in 2022

LoI 2024-2179
GA Symposium: A Fresh Look at Galaxy Clusters

Date: 5 August 2024 to 16 August 2024
Category: GA Symposium
Location: Cape Town, South Africa
Contact: Matt Hilton (matt.hilton@wits.ac.za)
Coordinating division: Division J Galaxies and Cosmology
Other divisions:
Co-Chairs of SOC: Matt Hilton (University of the Witwatersrand)
Kathy Romer (University of Sussex)
Mathilde Jauzac (Durham University)
Chair of LOC: None (None)



In no particular order:
1. Current and future galaxy cluster surveys
2. Diffuse radio emission in galaxy clusters
3. Galaxy clusters as cosmic telescopes
4. Cosmology and cluster mass calibration
5. Evolution of the intracluster medium / AGN feedback in clusters
6. Evolution of cluster galaxies and the intracluster light
7. Protoclusters
8. Tests of dark matter and modified gravity with galaxy clusters



A suite of new facilities coupled with large area sky surveys has given us the ability to study galaxy clusters and protoclusters over a wide range in redshift and across the electromagnetic spectrum, and promises to further our understanding of the cosmic evolution of all of their components - dark matter distribution, gas, galaxies, AGN - and the interactions between them. SKA precursor instruments such as MeerKAT and LOFAR are providing unprecedented views of diffuse, low surface brightness radio emission, often seen in colliding clusters. In space, the James Webb Space Telescope (JWST) promises a significant upgrade to the use of clusters as cosmic telescopes, and to cluster mass calibration. Large area optical/IR, Sunyaev-Zel'dovich, and all sky X-ray surveys are delivering large samples of clusters and protoclusters that span most of cosmic history, and can be used for cosmological tests. ALMA and current X-ray missions allow us to trace the evolution of hot cluster atmospheres and understand the role of AGN feedback in shaping cluster evolution. JWST and the Rubin Observatory will allow us to measure the evolution of diffuse stellar light in clusters in detail over a wide range in redshift, and understand its relation to the assembly history of clusters. The goal of the meeting will be to review progress in all areas of astrophysics and cosmology related to galaxy clusters using these new facilities, discuss connections between each of these areas, and look ahead to future work with facilities such as the SKA, Simons Observatory, CMB-S4, Athena, Euclid, and the Nancy Grace Roman Space Telescope.

We anticipate organising the symposium into a number of sessions with different science themes, as listed below. The order would be defined at a later stage, after receiving abstract submissions:

1. Diffuse radio emission in clusters - on the path to SKA
2. Upgrading cosmic telescopes with JWST observations
3. Testing cosmology, gravitation, and dark matter with galaxy clusters
4. Tracing the evolution of cluster atmospheres and AGN feedback
5. From protoclusters to clusters - the evolution of galaxies in dense environments

During the process of drafting the full proposal, we will reach out to community members to assemble the SOC, taking into account expertise, diversity, and geographical representation. We will also reach out to the community in South Africa in order to develop the outreach and education component.