A Baryonic Effect on the Merger Timescale of Galaxy Clusters

Abstract

Accurate estimation of the merger timescale of galaxy clusters is important to understand the cluster merger process and further the formation and evolution of the large-scale structure of the universe. In this paper, we explore a baryonic effect on the merger timescale of galaxy clusters by using hydrodynamical simulations. We find that the baryons play an important role in accelerating the merger process. The merger timescale decreases with increasing the gas fraction of galaxy clusters. For example, the merger timescale is shortened by a factor of up to 3 for merging clusters with gas fractions 0.15, compared with the timescale obtained with zero gas fractions. The baryonic effect is significant for a wide range of merger parameters and especially more significant for nearly head-on mergers and high merging velocities. The baryonic effect on the merger timescale of galaxy clusters is expected to have impacts on the structure formation in the universe, such as the cluster mass function and massive substructures in galaxy clusters, and a bias of "no-gas" may exist in the results obtained from the dark matter-only cosmological simulations.

9 pages, 6 figures, accepted for publication in the Astrophysical Journal

References in corpus (9)

• The impact of mergers on relaxed X-ray clusters - I. Dynamical evolution and emergent transient structures
• A fitting formula for the merger timescale of galaxies in hierarchical clustering
• The Nearly Universal Merger Rate of Dark Matter Haloes in Lambda-CDM Cosmology
• Cosmology and Astrophysics from Relaxed Galaxy Clusters II: Cosmological Constraints
• The Effect of Gas Physics on the Halo Mass Function
• Simulating the galaxy cluster "El Gordo" and identifying the merger configuration
• Offsets between the X-ray and the Sunyaev-Zel'dovich-effect peaks in merging galaxy clusters and their cosmological implications
• Probing dark energy models with extreme pairwise velocities of galaxy clusters from the DEUS-FUR simulations
• Statistics of Dark Matter Substructure: II. Comparison of Model with Simulation Results

Cited by in corpus (16)

• In the Wake of Dark Giants: New Signatures of Dark Matter Self Interactions in Equal Mass Mergers of Galaxy Clusters
• Weak lensing Analysis of X-Ray-selected XXL Galaxy Groups and Clusters with Subaru HSC Data
• On the dynamical state of galaxy clusters: insights from cosmological simulations II
• Forming intracluster gas in a galaxy protocluster at a redshift of 2.16
• Encounters of Merger and Accretion Shocks in Galaxy Clusters and their Effects on Intracluster Medium
• Cosmology dependency of halo masses and concentrations in hydrodynamic simulations
• Imprints of Mass Accretion History on the Shape of the Intracluster Medium and the $T_X-M$ Relation
• N-body simulations of dark matter with frequent self-interactions
• Multi-scale analysis of turbulence evolution in the density stratified intracluster medium
• Observational evidence for bar formation in disk galaxies via cluster-cluster interaction
• The Three Hundred: Cluster Dynamical States and Relaxation Time Scale
• Simulated Analogs of Merging Galaxy Clusters Constrain the Viewing Angle
• Evolution of Splashback Boundaries and Gaseous Outskirts: Insights from Mergers of Self-similar Galaxy Clusters
• Turbulence decay in the density-stratified intracluster medium
• Dynamics of Merging Galaxy Clusters from Simulated Analogs
• Unequal-mass mergers of dark matter haloes with rare and frequent self-interactions