J/A+A/633/A139 Abundances of RXC J2248.7-4431 galaxies (Ciocan+, 2020)
CLASH-VLT: Enhancement of (O/H) in z = 0.35 RX J2248-4431 cluster galaxies.
Ciocan B.I., Maier C., Ziegler B.L., Verdugo M.
<Astron. Astrophys., 633, A139 (2020)>
=2020A&A...633A.139C 2020A&A...633A.139C (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxy catalogs ; Abundances
Keywords: Galaxy: evolution - galaxies: clusters: individual: RX J2248-443 -
galaxies: star formation - galaxies: abundances
Abstract:
Aims. Gas-phase metallicities offer insight into the chemical
evolution of galaxies as they reflect the recycling of gas through
star formation and galactic inflows and outflows. Environmental
effects such as star-formation quenching mechanisms play an important
role in shaping the evolution of galaxies. Clusters of galaxies at
z<0.5 are expected to be the sites where environmental effects can be
clearly observed with present-day telescopes. Methods. We explored the
Frontier Fields cluster RX J2248-443 at z=0.348 with VIMOS/VLT
spectroscopy from CLASH-VLT, which covers a central region
corresponding to almost 2 virial radii. The fluxes of
[OII]λ3727, Hβ, [OIII]λ5007, Hα and
[NII]λ6584 emission lines were measured allowing the derivation
of (O/H) gas metallicities, star formation rates based on
extinction-corrected Hα fluxes, and contamination from active
galactic nuclei. We compared our sample of cluster galaxies to a
population of field galaxies at similar redshifts. Results. We use the
location of galaxies in projected phase-space to distinguish between
cluster and field galaxies. Both populations follow the star-forming
sequence in the diagnostic diagrams, which allow the ionising sources
in a galaxy to be disentangled, with only a low number of galaxies
classified as Seyfert II. Both field and cluster galaxies follow the
"main sequence" of star-forming galaxies, with no substantial
difference observed between the two populations. In the
mass-metallicity (MZ) plane, both high-mass field and cluster galaxies
show comparable (O/H)s to the local SDSS MZ relation, with an offset
of low-mass galaxies (log(M/M☉)<9.2) towards higher
metallicities. While both the metallicities of "accreted" (R<R500)
and "infalling" (R>R500) cluster members are comparable at all
masses, the cluster galaxies from the "mass complete" bin (which is
the intermediate mass bin in this study: 9.2<log(M/M☉)<10.2),
show more enhanced metallicities than their field counterparts by a
factor of 0.065 dex with a ∼1.8σ significance. The
intermediate-mass field galaxies are in accordance with the expected
(O/H)s from the fundamental metallicity relation, while the cluster
members deviate strongly from the model predictions, namely by a
factor of ∼0.12dex. The results of this work are in accordance with
studies of other clusters at z<0.5 and favour the scenario in which
the hot halo gas of low- and intermediate-mass cluster galaxies is
removed due to ram pressure stripping, leading to an increase in their
gas-phase metallicity.
Description:
Catalog of 178 galaxies of RX J2248-443 cluster (z∼0.35), with
chemical abundances derived from several diagnostics based on strong
emission lines (ELs) such as: Hβ, [OIII]λ5007, Hα,
and [NII]λ6584.
Objects:
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RA (2000) DE Designation(s)
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22 48 54.3 -44 31 07 RXC J2248.7-4431 = ACO S 1063
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 65 178 Catalogue for the RX J2248 cluster galaxies
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Galaxy Galaxy identification number (1)
5- 9 F5.2 10-20W/m2 F(Hbeta) ? Hβ emission line flux
11- 14 F4.2 10-20W/m2 e_F(Hbeta) ? rms uncertainty on F(Hbeta)
16- 20 F5.2 10-20W/m2 F([OIII]) ? [OIII] emission line flux
22- 25 F4.2 10-20W/m2 e_F([OIII]) ? rms uncertainty on F([OIII])
27- 31 F5.2 10-20W/m2 F(Halpha) ? Hα emission line flux
33- 36 F4.2 10-20W/m2 e_F(Halpha) ? rms uncertainty on F(Halpha)
38- 42 F5.2 10-20W/m2 F([NII]) ? [NII] emission line flux
44- 47 F4.2 10-20W/m2 e_F([NII]) ? rms uncertainty on F([NII])
49- 54 F6.3 [Msun] logM Stellar mass, as computed by LePhare
56- 60 F5.2 [Gyr] logsSFR ? Specific SFR (2)
62- 65 F4.2 --- 12+log(O/H) ? 12+log(O/H) abundance
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Note (1): Galaxy IDs, coordinates, and redshift will be available in a future
publication (Mercurio et al., in prep.).
Note (2): as computed using the luminosity of the Hα emission line and
the oxygen abundance derived through the O3N2 method.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 15-Apr-2020