THE PROPERTIES OF X-RAY COLD FRONTS IN A STATISTICAL SAMPLE OF SIMULATED GALAXY CLUSTERS

Journal Article · Fri Dec 10 00:00:00 EST 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/725/1/1053· OSTI ID:21474383

Hallman, Eric J; Skillman, Samuel W; Smith, Britton D; Burns, Jack O ^[1]; Jeltema, Tesla E ^[2]; O'Shea, Brian W ^[3]

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1. Center for Astrophysics and Space Astronomy, Department of Astrophysics and Planetary Sciences, University of Colorado at Boulder, Boulder, CO 80309 (United States)
2. UCO/Lick Observatories, 1156 High St., Santa Cruz, CA 95064 (United States)
3. Department of Physics and Astronomy and Lyman Briggs College, Michigan State University, East Lansing, MI 48824 (United States)

We examine the incidence of cold fronts in a large sample of galaxy clusters extracted from a (512 h {sup -1} Mpc) hydrodynamic/N-body cosmological simulation with adiabatic gas physics computed with the Enzo adaptive mesh refinement code. This simulation contains a sample of roughly 4000 galaxy clusters with M {>=}10{sup 14} M{sub sun} at z = 0. For each simulated galaxy cluster, we have created mock 0.3-8.0 keV X-ray observations and spectroscopic-like temperature maps. We have searched these maps with a new automated algorithm to identify the presence of cold fronts in projection. Using a threshold of a minimum of 10 cold front pixels in our images, corresponding to a total comoving length L{sub cf}>156 h {sup -1} kpc, we find that roughly 10%-12% of all projections in a mass-limited sample would be classified as cold front clusters. Interestingly, the fraction of clusters with extended cold front features in our synthetic maps of a mass-limited sample trends only weakly with redshift out to z = 1.0. However, when using different selection functions, including a simulated flux limit, the trending with redshift changes significantly. The likelihood of finding cold fronts in the simulated clusters in our sample is a strong function of cluster mass. In clusters with M>7.5 x 10{sup 14} M{sub sun} the cold front fraction is 40%-50%. We also show that the presence of cold fronts is strongly correlated with disturbed morphology as measured by quantitative structure measures. Finally, we find that the incidence of cold fronts in the simulated cluster images is strongly dependent on baryonic physics.

• OSTI ID: 21474383
• Journal Information: Astrophysical Journal, Vol. 725, Issue 1; Other Information: DOI: 10.1088/0004-637X/725/1/1053; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ALGORITHMS
COMPUTERIZED SIMULATION
COSMOLOGICAL MODELS
GALAXY CLUSTERS
MORPHOLOGY
RED SHIFT
UNIVERSE
X RADIATION
X-RAY GALAXIES
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
ELECTROMAGNETIC RADIATION
GALAXIES
IONIZING RADIATIONS
MATHEMATICAL LOGIC
MATHEMATICAL MODELS
RADIATIONS
SIMULATION