J/A+A/678/A181 CHEX-MATE clusters hydrogen column densities (Bourdin+, 2023)
CHEX-MATE: X-ray absorption and molecular content of the interstellar medium
toward galaxy clusters.
Bourdin H., De Luca F., Mazzotta P., Bartalucci I., Donahue M., Eckert D.,
Ettori S., Gastaldello F., Ghizzardi S., Kay S., Lovisari L., Maughan B.,
Oppizzi F., Pointecouteau E., Pratt G.W., Rossetti M., Sereno M.
<Astron. Astrophys., 678, A181 (2023)>
=2023A&A...678A.181B 2023A&A...678A.181B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Interstellar medium ; H I data
Keywords: dust - extinction - galaxies: clusters: intracluster medium
Abstract:
The X-ray spectrum of extragalactic sources, such as galaxy clusters,
is affected by the photo-absorption of various components of the
Galactic interstellar medium (ISM). The resulting spectral distortion
contributes to the systematics of cluster temperature measurements. It
essentially depends on the neutral (atomic+molecular) Galactic
hydrogen density column, NH, which remains challenging to map across
the sky in the lack of a straightforward tracer of the molecular gas
phase in the ISM. Combining data from the HI4PI and Planck HFI sky
surveys, we investigate the mass fraction of molecular gas across the
line of sight of CHEX-MATE galaxy clusters by searching for thermal
dust emission excess with respects to the neutral atomic hydrogen
density column, NHI. Consistent with earlier studies of the ISM
based on IRAS and Planck data, we detect dust emission excess along
the line of sight of some members of the CHEX-MATE cluster catalogue
that are mostly localised behind dense ISM regions. We find that the
CHEX-MATE cluster catalogue can be divided into three categories: 40%
of members are located behind low NHI regions where the molecular
mass fraction is negligible, 40% of members are located behind
intermediate NHI regions where the molecular gas fraction would
reach 5% on average, and the remaining 20% of members are located
behind high NHI regions that locally exhibit even higher molecular
gas fractions. The apparent cluster temperature shifts associated with
the molecular content of the ISM are about 1% or less for most
CHEX-MATE clusters, but can exceed 5% in the highest NHI regions.
Description:
This work relies on the (sub)-millimeter sky survey performed with
Planck and the two radio sky surveys Leiden, Argentine, and Bonn (LAB,
Kalberla et al., 2005A&A...440..775K 2005A&A...440..775K, Cat. VIII/76) and HI 4{PI}
(HI4PI, HI4PI Collaboration, 2016A&A...594A.116H 2016A&A...594A.116H, Cat.
J/A+A/594/A116).
We used Planck data registered with the High Frequency Instrument
(HFI) for the second data release, which covered the full mission in
2015 (Planck Collaboration VIII, 2016A&A...594A...8P 2016A&A...594A...8P).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 82 112 Mass fraction of molecular hydrogen (f) and
total hydrogen density column (NH) estimates
toward CHEX-MATE clusters
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See also:
J/A+A/594/A27 : Planck Sunyaev-Zeldovich sources (PSZ2) (Planck+, 2016)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- ID Planck ID (PSZ2GLLL.ll+BB.BBAA)
21- 30 F10.6 deg RAdeg Right ascension (J2000)
32- 40 F9.5 deg DEdeg Declination (J2000)
42- 45 F4.2 10+20cm-2 NHI(HI4PI) HI4PI total HI column density
47- 50 F4.2 --- f Planck+HI4PI f=2NH2/NH ratio (1)
52- 55 F4.2 --- e_f Planck+HI4PI f=2NH2/NH ratio error
57- 61 F5.2 10+20cm-2 NH(Pl+HI4PI) Planck+HI4PI total H column density (1)
63- 66 F4.2 10+20cm-2 e_NH(Pl+HI4PI) Planck+HI4PI total H column density
error
68- 72 F5.2 10+20cm-2 NH(XMM) ?=- XMM total H column density (1)
74- 77 F4.2 10+20cm-2 E_NH(XMM) ? XMM total H column density error
78 A1 --- --- [-]
79- 82 F4.2 10+20cm-2 e_NH(XMM) ? XMM total H column density error
(lower value)
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Note (1): f and NH derive from three averaged values of these quantities and
associated uncertainties in the intra-cluster radius range [3,6]xr500.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 15-Jan-2024