CuspCore · Dark Matter Cusps and Cores by Violent Relaxation
Horizon Europe — Marie Skłodowska-Curie Actions
- Duration
- 2023-05-01 → 2025-05-31
- EU contribution
- €200,538
- Participants
- 1
- Scheme
- HORIZON-TMA-MSCA-PF-EF
Lines connect the coordinator with its partners.
Results in brief
Dark Matter Cusps and Cores by Violent Relaxation
The standard model of cosmology, which describes the universe as being dominated by cold dark matter (DM), has been remarkably successful. However, it faces significant challenges on the scale of individual galaxies. Observations have revealed that some galaxies, from massive ones in the early universe to small dwarf galaxies nearby, appear to contain far less dark matter in their centers than predicted. This discrepancy, known as the "cusp-core problem," questions our understanding of how galaxies form and evolve. Recent discoveries from new observatories like the James Webb Space Telescope have only intensified these questions. The CuspCore project was launched to address this fundamental problem. Its primary objective was to develop a new, comprehensive theoretical framework to understand the dynamic processes that shape the structure of galaxies and their host DM halos. The project aimed to explain the observed diversity in galaxy structures by modeling key physical mechanisms, such as powerful gas outflows from galactic centers and the gravitational stripping of material from satellite galaxies. By accurately modeling these processes, the project sought to resolve the existing tensions within the standard cosmological model, providing a more complete picture of galaxy formation. The expected impact was a significant advancement in our fundamental knowledge, providing new theoretical tools to the global astrophysics community.
Data: CORDIS, © European Union
Project objective
We address both the long-standing puzzle of the origin of a universal cusp in dark-matter (DM) halos and the challenge introduced by new observational indications for a dearth of central DM and flat cores in a certain fraction of the galaxies. Such DM-deficient cores are reported both in massive galaxies at high redshifts and in dwarf galaxies, contrary to the expectations for a cusp based on current simulations within the standard LCDM cosmological scenario. We propose to better understand the structural evolution of DM halos in response to drastic mass changes and the gravitational interplay between the DM and the baryons, including inflows, mergers, tidal effects, and outflows. For this, we will develop our analytic model, CuspCore, which would provide a unified framework for following the violent relaxation of a halo after it has been perturbed from an equilibrium configuration. Utilizing this framework, we will work out a scenario for DM-deficient cores in high-z massive galaxies via DM ""heating"" by dynamical friction on compact merging satellites followed by DM expansion in response to AGN-driven outflows. The same framework will serve to generate cores in dwarf galaxies via supernova feedback and tidal stripping. Finally, we will attempt to use this framework to understand the original universal cuspy profile of DM halos based on non-adiabatic growth. Success in modeling the violent-relaxation process in these circumstances will be crucial for meeting the immediate challenges to the standard cosmological model, and it promises a general impact on other broad applications of galactic dynamics.""
Original text from CORDIS.
Participants
- THE HEBREW UNIVERSITY OF JERUSALEM · JerusalemCoordinatorIsrael
Links
- View on CORDIS
- DOI: 10.3030/101109759
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e51c24f0d7&appId=PPGMS
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e51fa7281e&appId=PPGMS
Data: CORDIS, © European Union