Search Results - "Hallman, Eric"

Probing the Curious Case of a Galaxy Cluster Merger in Abell 115 with High-fidelity Chandra X-Ray Temperature and Radio Maps by Hallman, Eric J., Alden, Brian, Rapetti, David, Datta, Abhirup, Burns, Jack O.

“…We present results from an X-ray and radio study of the merging galaxy cluster Abell 115. We use the full set of five Chandra observations taken of A115 to…”
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COSMOLOGICAL MAGNETOHYDRODYNAMIC SIMULATIONS OF GALAXY CLUSTER RADIO RELICS: INSIGHTS AND WARNINGS FOR OBSERVATIONS by Skillman, Samuel W, Xu, Hao, Hallman, Eric J, O'Shea, N W, Burns, Jack O, Li, Hui, Collins, David C, Norman, Michael L

“…Non-thermal radio emission from cosmic-ray electrons in the vicinity of merging galaxy clusters is an important tracer of cluster merger activity, and is the…”
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The Nature of the Warm/Hot Intergalactic Medium. I. Numerical Methods, Convergence, and O VI Absorption by Smith, Britton D, Hallman, Eric J, Shull, J. Michael, O’Shea, Brian W

“…We perform a series of cosmological simulations using Enzo, an Eulerian adaptive-mesh refinement, N-body + hydrodynamical code, applied to study the warm/hot…”
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Diffuse radio emission in the galaxy cluster SPT-CL J2031−4037: a steep-spectrum intermediate radio halo? by Raja, Ramij, Rahaman, Majidul, Datta, Abhirup, Burns, Jack O, Intema, H T, van Weeren, R J, Hallman, Eric J, Rapetti, David, Paul, Surajit

“…ABSTRACT The advent of sensitive low-frequency radio observations has revealed a number of diffuse radio objects with peculiar properties that are challenging…”
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Cosmological Shocks in Adaptive Mesh Refinement Simulations and the Acceleration of Cosmic Rays by Skillman, Samuel W, O’Shea, Brian W, Hallman, Eric J, Burns, Jack O, Norman, Michael L

“…We present new results characterizing cosmological shocks within adaptive mesh refinement N-body/hydrodynamic simulations that are used to predict nonthermal…”
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Why Do Only Some Galaxy Clusters Have Cool Cores? by Burns, Jack O, Hallman, Eric J, Gantner, Brennan, Motl, Patrick M, Norman, Michael L

“…Flux-limited X-ray samples indicate that about half of rich galaxy clusters have cool cores. Why do only some clusters have cool cores while others do not? In…”
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Galaxy Cluster Radio Relics in Adaptive Mesh Refinement Cosmological Simulations: Relic Properties and Scaling Relationships by Skillman, Samuel W, Hallman, Eric J, O'Shea, Brian W, Burns, Jack O, Smith, Britton D, Turk, Matthew J

“…Cosmological shocks are a critical part of large-scale structure formation, and are responsible for heating the intracluster medium in galaxy clusters. In…”
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Probing the Origin of Diffuse Radio Emission in the Cool Core of the Phoenix Galaxy Cluster by Raja, Ramij, Rahaman, Majidul, Datta, Abhirup, Burns, Jack O., Alden, Brian, Intema, H. T., Weeren, R. J. van, Hallman, Eric J., Rapetti, David, Paul, Surajit

“…Cool core galaxy clusters are considered to be dynamically relaxed clusters with regular morphology and highly X-ray luminous central region. However, cool…”
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The Integrated Sunyaev-Zeldovich Effect as a Superior Method for Measuring the Mass of Clusters of Galaxies by Motl, Patrick M, Hallman, Eric J, Burns, Jack O, Norman, Michael L

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Structure and turbulence in simulated galaxy clusters and the implications for the formation of radio haloes by Hallman, Eric J., Jeltema, Tesla E.

“…We track the histories of massive clusters of galaxies formed within a cosmological hydrodynamic simulation. Specifically, we track the time evolution of the…”
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Cluster Structure in Cosmological Simulations. I. Correlation to Observables, Mass Estimates, and Evolution by Jeltema, Tesla E, Hallman, Eric J, Burns, Jack O, Motl, Patrick M

“…We use Enzo, a hybrid Eulerian adaptive mesh refinement/N-body code including nongravitational heating and cooling, to explore the morphology of the X-ray gas…”
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X-ray Point Sources and Radio Galaxies in Clusters of Galaxies by Hart, Quyen N, Stocke, John T, Hallman, Eric J

“…Using Chandra imaging spectroscopy and Very Large Array L-band maps, we have identified radio galaxies at P (1.4 GHz)>= 3 X 1023 W Hz-1 and X-ray point sources…”
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Chandra Observation of the Merging Cluster A168: A Late Stage in the Evolution of a Cold Front by Hallman, Eric J, Markevitch, Maxim

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The Santa Fe Light Cone Simulation Project. I. Confusion and the Warm-Hot Intergalactic Medium in Upcoming Sunyaev-Zel'dovich Effect Surveys by Hallman, Eric J, O’Shea, Brian W, Burns, Jack O, Norman, Michael L, Harkness, Robert, Wagner, Rick

“…We present the first results from a new generation of simulated large sky coverage ( similar to 100 deg super(2)) Sunyaev-Zel'dovich effect (SZE) cluster…”
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On the Origin of Cool Core Galaxy Clusters: Comparing X-ray Observations with Numerical Simulations by Henning, Jason W, Gantner, Brennan, Burns, Jack O, Hallman, Eric J

“…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 the…”
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HOW MUCH CAN WE LEARN FROM A MERGING COLD FRONT CLUSTER? INSIGHTS FROM X-RAY TEMPERATURE AND RADIO MAPS OF A3667 by DATTA, ABHIRUP, Schenck, David E, Burns, Jack O, Skillman, Samuel W, Hallman, Eric J

“…The galaxy cluster A3667 is an ideal laboratory to study the plasma processes in the intracluster medium. High-resolution Chandra X-ray observations show a…”
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Faster stochastic trace estimation with a Chebyshev product identity by Hallman, Eric

“…Methods for stochastic trace estimation often require the repeated evaluation of expressions of the form zTpn(A)z, where A is a symmetric matrix and pn is a…”
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The β-Model Problem: The Incompatibility of X-Ray and Sunyaev-Zeldovich Effect Model Fitting for Galaxy Clusters by Hallman, Eric J, Burns, Jack O, Motl, Patrick M, Norman, Michael L

“…We have analyzed a large sample of numerically simulated clusters to demonstrate the adverse effects resulting from the use of X-ray-fitted beta -model…”
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How Well do Cosmological Simulations Reproduce Individual Halo Properties? by Trenti, Michele, Smith, Britton D, Hallman, Eric J, Skillman, Samuel W, Shull, J. Michael

“…Cosmological simulations of galaxy formation often rely on prescriptions for star formation and feedback that depend on halo properties such as halo mass,…”
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A multilevel approach to stochastic trace estimation by Hallman, Eric, Troester, Devon

“…This article presents a randomized matrix-free method for approximating the trace of f(A), where A is a large symmetric matrix and f is a function analytic in…”
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