J/ApJS/182/12 ICM entropy profiles (ACCEPT) (Cavagnolo+, 2009)
Intracluster medium entropy profiles for a Chandra archival sample of
galaxy clusters.
Cavagnolo K.W., Donahue M., Voit G.M., Sun M.
<Astrophys. J. Suppl. Ser., 182, 12-32 (2009)>
=2009ApJS..182...12C 2009ApJS..182...12C
ADC_Keywords: X-ray sources ; Clusters, galaxy ; Redshifts
Keywords: astronomical data bases: miscellaneous - cooling flows
X-rays: galaxies: clusters - X-rays: general
Abstract:
We present radial entropy profiles of the intracluster medium (ICM)
for a collection of 239 clusters taken from the Chandra X-ray
Observatory's Data Archive. We find that most ICM entropy profiles are
well fitted by a model which is a power law at large radii and
approaches a constant value at small radii:
K(r)=K0+K100(r/100kpc)α, where K0 quantifies the typical
excess of core entropy above the best-fitting power law found at
larger radii. For completeness, we include previously unpublished
optical spectroscopy of Hα and [NII] emission lines discussed in
Cavagnolo et al. (2008ApJ...683L.107C 2008ApJ...683L.107C). All data and results
associated with this work are publicly available via the project Web
site (ACCEPT: Archive of Chandra Cluster Entropy Profile Tables).
Description:
Our sample is collected from observations taken with the Chandra X-ray
Observatory and which are publicly available in the CDA (Chandra Data
Archive) as of 2008 August.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 78 320 Summary of sample
table5.dat 96 960 Summary of entropy profile fits
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-)
http://www.pa.msu.edu/astro/MC2/accept : Home page of the project
J/A+A/396/397 : Deep cluster survey in Chandra archival data (Boschin+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Cluster name
20- 24 I5 --- ObsID Chandra observation identifier
26- 27 I2 h RAh Cluster Hour of Right Ascension (J2000)
29- 30 I2 min RAm Cluster Minute of Right Ascension (J2000)
32- 37 F6.3 s RAs Cluster Second of Right Ascension (J2000)
39 A1 --- DE- Cluster Sign of the Declination (J2000)
40- 41 I2 deg DEd Cluster Degree of Declination (J2000)
43- 44 I2 arcmin DEm Cluster Arcminute of Declination (J2000)
46- 50 F5.2 arcsec DEs Cluster Arcsecond of Declination (J2000)
52- 56 F5.1 ks Exp Exposure time
58- 59 A2 --- ACIS CCD location of cluster center
61- 66 F6.4 --- z Redshift
68- 72 F5.2 keV <kT> Average cluster temperature
74- 78 A5 --- Notes Assigned note(s) (1)
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Note (1): Notes as follows:
a = Clusters analyzed using the best-fit β-model for the surface
brightness profiles (discussed in Sect. 3.2);
b = Clusters with complex surface brightness of which only the central
regions were used in fitting K(r);
c = Clusters only used during analysis of the HIFLUGCS sub-sample
(discussed in Sect. 5.4);
d = Clusters with central AGN removed during analysis
(discussed in Sect. 3.5);
e = Clusters with central compact source removed during analysis
(discussed in Sect. 3.5);
f = Clusters with central bin ignored during fitting
(discussed in Sect. 3.5).
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Cluster name
20- 23 A4 --- Meth ?=- Method of TX interpolation in inner
region: flat or ext (linear extrapolation)
25- 26 I2 --- Nbin ? Number of radial bins in fit
28- 31 F4.2 Mpc rmax ? Maximum radius for fit
33- 37 F5.1 keV.cm2 K0 Best-fit core entropy (K=Tx.ne-2/3)
39- 44 F6.2 keV.cm2 e_K0 ? Uncertainty in K0
46- 50 F5.1 --- sigK0 ? Number of sigma K0 is away from zero
52- 58 F7.1 keV.cm2 K100 Best-fit entropy at 100kpc
60- 65 F6.1 keV.cm2 e_K100 Uncertainty in K100
67- 70 F4.2 --- alpha Best-fit power-law index
72- 75 F4.2 --- e_alpha Uncertainty in alpha
77- 78 I2 --- DOF Degrees of Freedom in fit
80- 86 F7.2 --- chi2 The χ2 of best-fit model
88- 96 A9 --- p-val Probability of worse fit given chi2 and DOF
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 17-Nov-2009