Properties of Cosmic Shock Waves in Large-Scale Structure Formation

By Francesco Miniati, D. Ryu, Hyesung Kang, T. Jones, Renyue Cen, Jeremiah P. Ostriker University of Minnesota, Chungnam National University, Pusan National University, Princeton Univeristy Observatory. 2000

246 citations recorded by the source corpus.

We have examined the properties of shock waves in simulations of large-scale structure formation. Two cosmological scenarios have been considered: a standard cold dark matter model with ΩM = 1 (SCDM), and a cold dark matter model with cosmological constant and ΩM + ΩΛ = 1 (ΛCDM) having ΩΛ = 0.55. Large-scale shocks result from accretion onto sheets, filaments, and knots of mass distribution on a scale of the order of ~5 h-1 Mpc in both scenarios. Energetic motions, partly residuals of past accretion processes and partly caused by current asymmetric inflow along filaments, end up generating additional shocks. These extend on a scale of the order of ~1 h-1 Mpc and envelop and penetrate deep inside the clusters. Collisions between substructures inside clusters also form merger shocks. Consequently, the topology of the shocks is very complex and highly connected. During cosmic evolution the comoving shock surface density decreases, reflecting the ongoing structure merger process in both scenarios. Accretion shocks have very high Mach numbers, typically between 10 and a few ×103, when photoheating of the preshock gas is not included. The characteristic shock velocity is of the order of vsh(z) = H(z)λnl(z), where λnl(z) is the wavelength scale of the nonlinear perturbation at the given epoch. However, the Mach number for merger and flow shocks (which occur within clusters) is usually smaller, in the range of ~3-10, corresponding to the fact that the intracluster gas is hot (i.e., already shock heated). Statistical fits of shock velocities around clusters as a function of cluster temperature give power-law functions in accord with those predicted by one-dimensional solutions. On the other hand, a very different result is obtained for the shock radius, reflecting extremely complex shock structures surrounding clusters of galaxies in three-dimensional simulations. The amount of inflowing kinetic energy across the shocks around clusters, which represents the power available for cosmic-ray acceleration, is comparable to the cluster X-ray luminosity emitted from a central region of radius 0.5 h-1 Mpc. Considering their large size and long lifetimes, those shocks are potentially interesting sites for cosmic-ray acceleration, if modest magnetic fields exist within them.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/c415705f3a0e54b363e04387259882cd4376d406

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Nuclear and High Energy Physics

Citations in the corpus

Radio signature of cosmological structure formation shocks (2006, background): “Numerical simulations indicate that those accretion (or ‘external’) shocks reach Mach numbers ≫ 10 (Miniati et al. 2000; Ryu et al. 2003; Pfrommer et al. 2006; Hoeft et al. 2006).”
DIFFUSIVE SHOCK ACCELERATION SIMULATIONS OF RADIO RELICS (2012, background): “Shock waves are indeed common in the intergalactic space (e.g., Miniati et al. 2000; Ryu et al. 2003).”
Detecting shock waves in cosmological smoothed particle hydrodynamics simulations (2006, background): “…of structure formation, both due to infalling pristine cosmic plasma which accretes onto filaments, sheets and haloes, as well as due to spersonic flows associated with merging substructures (Quilis et al. 1998; Miniati et al. 2000; Ryu et al. 2003; Gabici & Blasi 2003; Pavlidou & Fields 2005).”
Constraining the population of cosmic ray protons in cooling flow clusters with γ-ray and radio observations: Are radio mini-halos of hadronic origin? (2003, background): “Detailed studies have been undertaken on shocks of cosmological scales (Miniati et al. 2000; Takizawa & Naito 2000).”
Alfvénic reacceleration of relativistic particles in galaxy clusters: MHD waves, leptons and hadrons (2003, background): “Some results from numerical simulations suggest the presence of a large fraction of high Mach number shocks in cluster mergers (Miniati et al. 2000, 2001).”
PROBING THE INFLATON: SMALL-SCALE POWER SPECTRUM CONSTRAINTS FROM MEASUREMENTS OF THE COSMIC MICROWAVE BACKGROUND ENERGY SPECTRUM (2012, background): “…energy release because ofsupernovae(Oh et al. 2003); shocks during large scalestructure formation(Sunyaev & Zeldovich 1972; Cen & Ostriker 1999; Miniati et al. 2000);unresolved SZ clusters(Markevitch et al. 1991); the thermal SZ effect and second order Doppler effect from reionization(McQuinn…”
Cosmic-Ray Protons Accelerated at Cosmological Shocks and Their Impact on Groups and Clusters of Galaxies (2001, background): “The details of the group/cluster identiÐcation procedure can be found in Miniati et al. (2000).”
The Astrophysics of Ultrahigh-Energy Cosmic Rays (2011, unknown): “Clusters of galaxies have been considered as promising accelerators by various authors: Norman et al. (1995b); Kang et al. (1996, 1997); Miniati et al. (2000); Ryu & Kang (2003); Inoue et al. (2005, 2007); Murase et al. (2008a).”
Reviving fossil radio plasma in clusters of galaxies by adiabatic compression in environmental shock waves (2000, background): “The flows of the cosmological large-scale structure formation are predicted to produce frequently shock waves at the boundaries of clusters and filaments of galaxies and during cluster merger (Quilis et al., 1998; Miniati et al., 2000b).”
Shock waves in Eulerian cosmological simulations: main properties and acceleration of cosmic rays (2008, methodology): “This subject has been already investigated in several papers under different numerical approaches (Miniati et al. 2000, 2001; Keshet et al. 2003; Ryu et al. 2003; Pfrommer et al. 2006; Kang et al. 2007; Pfrommer et al. 2007).6 We study shock waves by means of a post-processing procedure.”
ON THE CLUSTER PHYSICS OF SUNYAEV–ZEL'DOVICH AND X-RAY SURVEYS. I. THE INFLUENCE OF FEEDBACK, NON-THERMAL PRESSURE, AND CLUSTER SHAPES ON Y–M SCALING RELATIONS (2011, background): “Those accretion shocks are typically forming at radii> R200 as suggested by numerical simulations (Miniati et al. 2000; Ryu et al. 2003; Pfrommer et al. 2006b; Skillman et al. 2008; Vazza et al. 2009) or indirectly by the action of shock waves on radio plasma bubbles, which represents a novel…”
Cosmic-Ray Electrons in Groups and Clusters of Galaxies: Primary and Secondary Populations from a Numerical Cosmological Simulation (2001, methodology): “…there is a possible tendency for the Mach numbers we compute to be slightly overestimated, especially in regions close to the cluster core, where with moderate spatial resolution the shock compression can be ““ confused ÏÏ by the gravitational compression (see Miniati et al. 2000 for details).”
Cosmological Shock Waves and Their Role in the Large-Scale Structure of the Universe (2003, methodology): “The properties of cosmological shock waves in the large scale structure of the universe were analyzed quantitatively by Miniati et al. (2000) using numerical simulations with 2703 grid zones in a cubic comoving region of size 85h−1 Mpc for a SCDM model and a ΛCDM model.”