We study the properties of cosmological shock waves identified in high-resolution, N-body/hydrodynamic simulations a $Λ$CDM universe and their role on thermalization gas acceleration nonthermal, cosmic ray (CR) particles. External shocks form around sheets, filaments knots mass distribution when void regions accretes onto them. Within those nonlinear structures, internal are produced by infall previously shocked to knots, during subclump mergers, as well chaotic flow motions. Due low...

We investigate empirical scaling relations between the thermal Sunyaev-Zeldovich effect (SZE) and cluster mass in simulated clusters of galaxies. The have been compiled from four different samples that differ only their assumed baryonic physics. show strength SZE integrated over a significant fraction virialized region is relatively insensitive to detailed heating cooling processes cores clusters, by demonstrating derived are nearly identical among considered. For our synthetic images,...

We present new results characterizing cosmological shocks within adaptive mesh refinement N-Body/hydrodynamic simulations that are used to predict non-thermal components of large-scale structure. This represents the first study using refinement. propose a modified algorithm for finding from those on unigrid reduces shock frequency low Mach number by factor ~3. then apply our technique large, (512 Mpc/h)^3, volume and (M) distribution as function pre-shock temperature, density, redshift....

Non-thermal radio emission from cosmic-ray electrons in the vicinity of merging galaxy clusters is an important tracer cluster merger activity, and result complex physical processes that involve magnetic fields, particle acceleration, gas dynamics, radiation. In particular, objects known as relics are thought to be shock-accelerated that, when embedded a field, emit synchrotron radiation wavelengths. order properly model this emission, we utilize adaptive mesh refinement simulation...

Flux-limited X-ray samples indicate that about half of rich galaxy clusters have cool cores. Why do only some cores while others not? In this paper, cosmological N-body + Eulerian hydrodynamic simulations, including radiative cooling and heating, are used to address question as we examine the formation evolution core (CC) non-cool (NCC) clusters. These adaptive mesh refinement simulations produce both CC NCC in same volume. They a peak resolution 15.6 h^{-1} kpc within (256 Mpc)^3 box. Our...

We perform a series of cosmological simulations using Enzo, an Eulerian adaptive-mesh refinement, N-body + hydrodynamical code, applied to study the warm/hot intergalactic medium. The WHIM may be important component baryons missing observationally at low redshift. investigate dependence global star formation rate and mass fraction in various baryonic phases on spatial resolution methods incorporating stellar feedback. Although both feedback significantly affect total WHIM, all our find that...

Cosmological shocks are a critical part of large-scale structure formation, and responsible for heating the intracluster medium in galaxy clusters. In addition, they capable accelerating non-thermal electrons protons. this work, we focus on acceleration at shock fronts, which is thought to be radio relics—extended features vicinity merging By combining high-resolution adaptive mesh refinement/N-body cosmological simulations with an accurate shock-finding algorithm model electron...

.The tensor-train (TT) format is a highly compact low-rank representation for high-dimensional tensors. TT particularly useful when representing approximations to the solutions of certain types parametrized partial differential equations. For many these problems, computing solution explicitly would require an infeasible amount memory and computational time. While makes problems tractable, iterative techniques solving PDEs must be adapted perform arithmetic while maintaining implicit...

Recent X-ray observations reveal growing evidence for heating by active galactic nuclei (AGNs) in clusters and groups of galaxies. AGN outflows play a crucial role explaining the riddle cooling flows entropy problem clusters. Here we study effect AGNs on intracluster medium cosmological simulation using adaptive mesh refinement FLASH code. We pay particular attention to effects conductivity viscosity dissipation weak shocks generated activity realistic galaxy cluster. Our three-dimensional...

We present the first results from a new generation of simulated large sky coverage (~100 deg2) Sunyaev-Zel'dovich effect (SZE) cluster surveys using cosmological adaptive mesh refinement N-body/hydro code Enzo. have very (5123 h-3 Mpc3) volume with unprecedented dynamic range. generated light cones to match resolution and sensitivity current future SZE instruments. Unlike many previous studies this type, our simulation includes unbound gas, where an appreciable fraction baryons in universe...

We use Enzo, a hybrid Eulerian adaptive mesh refinement/N-body code including nongravitational heating and cooling, to explore the morphology of X-ray gas in clusters galaxies its evolution current-generation cosmological simulations. employ compare two observationally motivated structure measures: power ratios centroid shift. Overall, our simulated compares remarkably well low-redshift observations, although some differences remain that may point incomplete physics. find no dependence on...

Cosmological simulations of galaxy formation often rely on prescriptions for star and feedback that depend halo properties such as mass, central overdensity, virial temperature. In this paper, we address the convergence individual properties, based their number particles N, focusing, in particular, mass halos near resolution limit a simulation. While it has been established function is sampled average down to N ∼ 20–30 particles, show exhibit significant scatter, some systematic biases, one...

.We introduce an algorithm for estimating the trace of a matrix function \(f(\mathbf{A})\) using implicit products with symmetric \(\mathbf{A}\) . Existing methods estimation tend to treat matrix-vector as black box be computed by Krylov subspace method. Like other recent algorithms estimation, our approach is based on combination deflation and stochastic estimation. However, we take closer look at how are integrated into these approaches which enables several efficiencies not present in...

We present Chandra observations of the cool cluster A168, for which previous X-ray imaging and optical studies indicated a merger two subclusters nearly in plane sky. derive temperature map shows that has proceeded beyond core passage is near subcluster turnaround. It also reveals an unusual feature: gas one forms tonguelike structure extending ahead (in direction motion) center. The coolest found crescent-shaped region at tip this tongue cold front pressure equilibrium with external gas. In...

We have analyzed a large sample of numerically simulated clusters to demonstrate the adverse effects resulting from use X-ray fitted beta-model parameters with Sunyaev-Zeldovich effect (SZE) data. There is fundamental incompatibility between model fits surface brightness profiles and those done SZE profiles. Since observational radial are in short supply, often used analysis. show that this leads biased estimates integrated Compton y-parameter inside r_{500} calculated clusters. suggest...

We present results from an X-ray and radio study of the merging galaxy cluster Abell 115. use full set 5 Chandra observations taken A115 to date (360 ks total integration) construct high-fidelity temperature surface brightness maps. also examine data Very Large Array at 1.5 GHz Giant Metrewave Radio Telescope 0.6 GHz. propose that high spectral between subclusters interaction bow shocks driven into intracluster medium by motion relative one another. have identified morphologically similar...

Using Chandra imaging spectroscopy and Very Large Array L-band maps, we have identified radio galaxies at P(1.4 GHz)⩾ 3 × 1023 W Hz−1 X-ray point sources (XPSs) L(0.3–8 keV)⩾ 1042 erg s−1 in 11 moderate redshift (0.2 < z 0.4) clusters of galaxies. Each cluster is uniquely chosen to a total mass similar predicted progenitors the present-day Coma Cluster. Within projected radius 1 Mpc detect 20 8 XPSs (three are detected both radio) confirmed be members above these limits. Of these, 75% within...

The galaxy cluster A3667 is an ideal laboratory to study the plasma processes in intracluster medium. High-resolution Chandra X-ray observations show a cold front A3667. At radio wavelengths, reveals double radio-relic feature outskirts of cluster. These suggest multiple merger events this In paper, we analyze substantial archival from Observatory and compare these with existing as well state-of-the-art adaptive mesh refinement MHD cosmological simulations using Enzo. We have used two...

Flux-limited X-ray surveys of galaxy clusters show that come in two roughly equally proportioned varieties: "cool core" (CCs) and non-"cool (NCCs). In previous work, we have demonstrated using cosmological N-body + Eulerian hydrodynamic simulations NCCs are often consistent with early major merger events destroy embryonic CCs. this paper extend those results conduct a series different methods gas cooling energy metal feedback from supernovae, where attempt to produce population realistic...

The advent of sensitive low frequency radio observations has revealed a number diffuse objects with peculiar properties that are challenging our understanding about the physics intracluster medium. Here, we report discovery steep spectrum halo surrounding central Brightest Cluster Galaxy (BCG) in galaxy cluster SPT-CL J2031-4037. This is morphologically disturbed yet weak cool core, an example core/non-cool core transition system, which harbours $\sim 0.7$ Mpc size. emission detected at 1.7...

We critically analyze the measurement of galaxy cluster gas masses, which is central to cosmological studies that rely on mass fraction. Using synthetic observations numerically simulated clusters viewed through their X-ray emission and thermal Sunyaev-Zeldovich effect (SZE), we reduce obtain measurements mass. are thus able quantify possible sources uncertainty systematic bias associated with common simplifying assumptions used in reducing real including isothermality hydrostatic...

We track the histories of massive clusters galaxies formed within a cosmological hydrodynamic simulation. Specifically, we time evolution energy in random bulk motions intracluster medium and X-ray measures cluster structure their relationship to mergers. aim assess viability turbulent re-acceleration model for generation giant radio halos by comparing level kinetic simulated with observed properties halo clusters, giving particular attention association disturbedX-ray structures. The...

Detection of the Warm-Hot Intergalactic Medium (WHIM) using Sunyaev–Zeldovich effect (SZE) surveys is an intriguing possibility, and one that may allow observers to quantify amount "missing baryons" in WHIM phase. We estimate necessary sensitivity for detecting low-density gas with South Pole Telescope (SPT) Planck Surveyor a synthetic 100 square degree sky survey. This survey generated from very large, high dynamic range adaptive mesh refinement cosmological simulation performed Enzo code....

To better constrain models of cool core galaxy cluster formation, we have used X-ray observations taken from the Chandra and ROSAT archives to examine properties noncool clusters, especially beyond cores. Using an optimized reduction process, produced images, surface brightness profiles, hardness ratio maps 30 nearby rich Abell clusters (17 cores 13 cores). We show that use double β with profiles single for yield statistically significant differences in slopes (i.e., values) outer but...