ABELL 2670 -- 4959

Cluster: ABELL 2670
ObsID: 4959

Download the master table of profiles for this cluster.

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Wide-Field Image	Cluster Core Image	SDSS Image
Light Curve	Surface Brightness Profile	Spectral Analysis
Temperature Profile	Gas Density Profile	Gas Pressure Profile
Entropy Profile	Cooling Time Profile

R.A.	Dec.	N_H	z	R_max	Min. cts.	T_X	Abund.	L_X
23:54:13.687	-10:25:08.85	2.88	0.0763	883	5000	3.98	0.25	1.39

Smoothed and binnd wide-field Chandra X-ray image of cluster
A gaussian smoothing kernel with size 2 was applied to the flare-cleaned, level-2 events file binned with a factor of 8 to produce this image. Point sources have not been excluded and no exposure correction has been applied to this image. This image was produced using SAOImage DS9, developed by the Smithsonian Astrophysical Observatory.

Smoothed and binned Chandra X-ray image of the cluster "core"
Same as the wide-field image above but the binning factor used here was 2.

Smoothed X-ray image of cluster along with SDSS image
Same as the previous two images except the corresponding field in SDSS is shown at right. The SDSS image is logarithmically scaled and not smoothed. Both frames have the same scaling and are matched using WCS coordinates to an astrometric accuracy of less than 0.25 of a Chandra pixel (~0.12").

SDSS image of cluster core
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Background light curve

To check for contamination from background flares or periods of excessively high background, light curve analysis was performed using Maxim Markevitch's contributed CIAO script lc_clean.sl. Periods with count rates >= 3sigma and/or a factor >= 1.2 of the mean background level of the observation were removed from the GTI file. As prescribed by Markevitch's cookbook, ACIS front-illuminated (FI) chips were analyzed in the 0.3-12.0 keV range with time bins of 259.28 sec in length, and for the ACIS back-illuminated (BI) chips, 2.5-7.0 keV energy range with time bins of 1037.12 sec.

Surface brightness profile

We began by extracting surface brightness profiles from the 0.7-2.0 keV energy range using concentric annular bins of size 5" (~10 ACIS pixels) originating from the X-ray center. To remove the effects of vignetting and exposure time fluctuations we corrected each surface brightness profile by an observation specific normalized radial exposure profile. The instrument map (and consequently exposure map) used for the exposure profile was created using a spectral weights file generated from Sherpa assuming a global cluster temperature and metallicity measured from the spectrum for an annulus with inner radius R=70 kpc and outer radius R₅₀₀₀.

Temperature bins
Tempus fugit

Links to images of spectra
Annulus 1	Annulus 2	Annulus 3	Annulus 4	Annulus 5
Annulus 6	Annulus 7	Annulus 8	Annulus 9

Temperature profile
Tempus fugit.

Density profile
Tempus fugit.

Pressure profile
Tempus fugit.

Entropy profile
Tempus fugit.

Cooling time profile
Tempus fugit.

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Kenneth W. Cavagnolo

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