This content will become publicly available on February 1, 2023
Exploring the relation between turbulent velocity and density fluctuations in the stratified intracluster medium
Context. The dynamics of the intracluster medium (ICM) is affected by turbulence driven by several processes, such as mergers, accretion and feedback from active galactic nuclei. Aims. X-ray surface brightness fluctuations have been used to constrain turbulence in galaxy clusters. Here, we use simulations to further investigate the relation between gas density and turbulent velocity fluctuations, with a focus on the effect of the stratification of the ICM. Methods. In this work, we studied the turbulence driven by hierarchical accretion by analysing a sample of galaxy clusters simulated with the cosmological code ENZO. We used a fixed scale filtering approach to disentangle laminar from turbulent flows. Results. In dynamically perturbed galaxy clusters, we found a relation between the root mean square of density and velocity fluctuations, albeit with a different slope than previously reported. The Richardson number is a parameter that represents the ratio between turbulence and buoyancy, and we found that this variable has a strong dependence on the filtering scale. However, we could not detect any strong relation between the Richardson number and the logarithmic density fluctuations, in contrast to results by recent and more idealised simulations. In particular, we find a strong effect from radial accretion, which more »
- Award ID(s):
- 1714205
- Publication Date:
- NSF-PAR ID:
- 10326091
- Journal Name:
- Astronomy & Astrophysics
- Volume:
- 658
- Page Range or eLocation-ID:
- A149
- ISSN:
- 0004-6361
- Sponsoring Org:
- National Science Foundation
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