J/A+A/686/A68 Temperature profiles for galaxy clusters (Rossetti+, 2024)
CHEX-MATE: Robust reconstruction of temperature profiles in galaxy clusters
with XMM-Newton.
Rossetti M., Eckert D., Gastaldello F., Rasia E., Pratt G.W., Ettori S.,
Molendi S., Arnaud M., Balboni M., Bartalucci I., Batalha R.M., Borgani S.,
Bourdin H., De Grandi S., De Luca F., De Petris M., Forman W., Gaspari M.,
Ghizzardi S., Iqbal A., Kay S., Lovisari L., Maughan B.J., Mazzotta P.,
Pointecouteau E., Riva G., Sayers J., Sereno M.
<Astron. Astrophys. 686, A68 (2024)>
=2024A&A...686A..68R 2024A&A...686A..68R (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Effective temperatures
Keywords: galaxies: clusters: general - galaxies: clusters: intracluster medium
Abstract:
The "Cluster HEritage project with XMM-Newton: Mass Assembly and
Thermodynamics at the Endpoint of structure formation" (CHEX-MATE) is
a multi-year Heritage program, to obtain homogeneous XMM-Newton
observations of a representative sample of 118 galaxy clusters. The
observations are tuned to reconstruct the distribution of the main
thermodynamic quantities of the ICM up to R500 and to obtain
individual mass measurements, via the hydrostatic-equilibrium
equation, with a precision of 15-20%. Temperature profiles are a
necessary ingredient for the scientific goals of the project and it is
thus crucial to derive the best possible temperature measurements from
our data. This is why we have built a new pipeline for spectral
extraction and analysis of XMM-Newton data, based on a new physically
motivated background model and on a Bayesian approach with Markov
Chain Monte Carlo (MCMC) methods, that we present in this paper for
the first time. We applied this new method to a subset of 30 galaxy
clusters representative of the CHEX-MATE sample and show that we can
obtain reliable temperature measurements up to regions where the
source intensity is as low as 20% of the background, keeping
systematic errors below 10%. We compare the median profile of our
sample and the best fit slope at large radii with literature results
and we find a good agreement with other measurements based on
XMM-Newton data. Conversely, when we exclude from our analysis the
most contaminated regions, where the source intensity is below 20 of
the background, we find significantly flatter profiles, in agreement
with predictions from numerical simulations and independent
measurements with a combination of Sunyaev-Zeldovich and X-ray imaging
data.
Description:
Table containing the temperature profiles used in the paper. The first
column shows the name of the cluster, while the second and third ones
show the sky extension R500 in arcminutes and the mean temperature,
estimated in the annulus between 0.15 and 0.75R500. Columns 4 and 5
report the coordinates of the center used for spectral extraction (the
peak in Bartalucci et al., 2023A&A...674A.179B 2023A&A...674A.179B), while columns 6 and 7
show the center of the radial bin R and the width dR (annulus included
between R-dR and R+dR). Columns 8, 9, and 10 report the best fit
temperature and its errors (downward and upward) obtained with our
baseline MCMC procedure, while column 11 shows the SOU/BKG ratio in
the radial bin.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 87 355 Temperature profiles for the clusters of our sample
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See also:
J/A+A/594/A27 : Planck Sunyaev-Zeldovich sources (PSZ2) (Planck+, 2016)
Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Cluster Name
19- 23 F5.2 arcmin R500 Cluster size
25- 29 F5.2 keV Tmean Mean cluster temperature
31- 38 F8.4 deg RAdeg Center right ascension (J2000)
40- 47 F8.4 deg DEdeg Center declination (J2000)
49- 55 F7.4 arcmin Radius Distance of the radial bin from the center
57- 62 F6.4 arcmin Width Width of the radial bin
64- 68 F5.2 keV T Best-fit temperature in the radial bin
70- 73 F4.2 keV e_T Downward error on temperature
75- 78 F4.2 keV E_T Upward error on temperature
80- 87 F8.2 --- SOU/BKG SOU/BKG in the radial bin (1)
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Note (1): Even a large error on the background model will not affect
significantly the best fit parameters in a region where the source outshines
the background, such as in the central regions of galaxy clusters,
conversely, in the external regions where the source intensity is comparable
to, or often even smaller than, the background level, even a few percent error
in the estimates of the background may affect significantly our temperature
measurements. To quantify this, following Leccardi & Molendi
(2008A&A...486..359L 2008A&A...486..359L), we define the indicator SOU/BKG for all DR1 clusters
and for all regions where we extracted spectra.. We compute it as
(OBS-BKG)/BKG, where OBS is the observed count rate and BKG is the predicted
count-rate by the best fit model of all the background components.
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Acknowledgements:
Maria-Chiara Rossetti, mariachiara.rossetti(at)inaf.it
References:
CHEX-MATE Collaboration, 2021A&A...650A.104C 2021A&A...650A.104C
Campitiello et al., 2022A&A...665A.117C 2022A&A...665A.117C
Oppizzi et al., 2023A&A...672A.156O 2023A&A...672A.156O
Bartalucci et al., 2023A&A...674A.179B 2023A&A...674A.179B
Bourdin et al., 2023A&A...678A.181B 2023A&A...678A.181B, Cat. J/A+A/678/A181
Iqbal et al., 2023A&A...679A..51I 2023A&A...679A..51I
(End) Patricia Vannier [CDS] 13-Mar-2024