J/A+A/597/A122 Cluster and field elliptical galaxies at z∼1.3 (Saracco+, 2017)
Cluster and field elliptical galaxies at z ∼ 1.3. The marginal role of the
environment and the relevance of the galaxy central regions.
Saracco P., Gargiulo A., Ciocca F., Marchesini D.
<Astron. Astrophys., 597, A122-122 (2017)>
=2017A&A...597A.122S 2017A&A...597A.122S (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxy catalogs ; Morphology
Keywords: galaxies: elliptical and lenticular, cD - galaxies: evolution -
galaxies: clusters: general - galaxies: high-redshift -
galaxies: formation
Abstract:
The aim of this work is twofold: first, to assess whether the
population of elliptical galaxies in cluster at z∼1.3 differs from the
population in the field and whether their intrinsic structure depends
on the environment where they belong; second, to constrain their
properties 9Gyr back in time through the study of their scaling
relations.
We compared a sample of 56 cluster elliptical galaxies selected from
three clusters at 1.2<z<1.4 with elliptical galaxies selected at
comparable redshift in the GOODS-South field (∼30), in the COSMOS area
(∼180), and in the CANDELS fields (∼220). To single out the
environmental effects, we selected cluster and field elliptical
galaxies according to their morphology. We compared physical and
structural parameters of galaxies in the two environments and we
derived the relationships between effective radius, surface
brightness, stellar mass, and stellar mass density ΣRe
within the effective radius and central mass density Σ1kpc,
within 1kpc radius.
We find that the structure and the properties of cluster elliptical
galaxies do not differ from those in the field: they are characterized
by the same structural parameters at fixed mass and they follow the
same scaling relations. On the other hand, the population of field
elliptical galaxies at z∼1.3 shows a significant lack of massive
(M*>2x1011M☉) and large (Re>4-5kpc) elliptical galaxies
with respect to the cluster. Nonetheless, at M*<2x1011M☉,
the two populations are similar. The size-mass relation of cluster and
field ellipticals at z∼1.3 clearly defines two different regimes,
above and below a transition mass mt~=2-3x1010M☉ at lower
masses the relation is nearly flat (Re∝M*-0.1±0.2), the
mean radius is nearly constant at ∼1kpc and, consequently,
ΣRe~=Σ1kpc while, at larger masses, the relation is
Re∝M*0.64±0.09. The transition mass marks the mass at which
galaxies reach the maximum stellar mass density. Also the
Σ1kpc-mass relation follows two different regimes, above and
below the transition mass (Σ1kpc∝M*1.07<mt0.64>mt)
defining a transition mass density
Σ1kpc~=2-3x103M☉/pc2. The effective stellar mass
density ΣRe does not correlate with mass; dense/compact
galaxies can be assembled over a wide mass regime, independently of
the environment. The central stellar mass density, Σ1kpc,
besides being correlated with the mass, is correlated to the age of
the stellar population: the higher the central stellar mass density,
the higher the mass, the older the age of the stellar population.
While we found some evidence of environmental effects on the
elliptical galaxies as a population, we did not find differences
between the intrinsic properties of cluster and field elliptical
galaxies at comparable redshift. The structure and the shaping of
elliptical galaxies at z∼1.3 do not depend on the environment.
However, a dense environment seems to be more efficient in assembling
high-mass large ellipticals, much rarer in the field at this redshift.
The correlation found between the central stellar mass density and the
age of the galaxies beside the mass shows the close connection of the
central regions to the main phases of mass growth.
Description:
The samples of galaxies used are covered by multiwavelength data in
the range 0.38-8.0um obtained from the Hubble Space Telescope
(HST) and Spitzer archival data, ground-based ESO-VLT archival data
and with observations obtained at the Large Binocular Telescope (LBT).
Cluster elliptical galaxies have been selected in the three clusters
XMM J2235-2557 at z=1.39 (Rosati et al., 2009A&A...508..583R 2009A&A...508..583R),
RDCS J0848+4453 at z=1.27 (Stanford et al.,
1997AJ....114.2232S 1997AJ....114.2232S), and XLSS-J0223-0436 at z=1.22 (Andreon et al.
2005MNRAS.359.1250A 2005MNRAS.359.1250A; Bremer et al., 2006MNRAS.371.1427B 2006MNRAS.371.1427B).
Our main sample of field ellipticals is composed of 31 ellipticals at
1.2<z<1.45 (27 at 1.2<z<1.4) in the GOODS-South field.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 114 56 Morphological parameters of cluster elliptical
galaxies
tableb2.dat 114 31 Morphological parameters of elliptical galaxies
in the field
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Byte-by-byte Description of file: tableb1.dat tableb2.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Cluster Cluster or field name (1)
14- 17 I4 --- ID Galaxy identification number
19- 20 I2 h RAh Right ascension (J2000)
22- 23 I2 min RAm Right ascension (J2000)
25- 30 F6.3 s RAs Right ascension (J2000)
32 A1 --- DE- Declination sign (J2000)
33- 34 I2 deg DEd Declination (J2000)
36- 37 I2 arcmin DEm Declination (J2000)
39- 44 F6.3 arcsec DEs Declination (J2000)
46- 48 F3.1 --- n850 Sersic index
50- 52 F3.1 --- e_n850 rms uncertainty on n850
54- 56 F3.1 --- b/a Axial ratio
58- 62 F5.2 mag F850fit F850LP apparent magnitude
64- 67 F4.2 mag e_F850fit rms uncertainty on F850fit
69- 72 F4.1 kpc ReF850 Effective radius as derived from the
fitting to the surface brightness
profile in the F850LP image
74- 76 F3.1 kpc e_ReF850 rms uncertainty on ReF850
78- 81 F4.1 mag/arcsec2 muF850 Effective surface brightness
83- 85 F3.1 mag/arcsec2 e_muF850 rms uncertainty on ReF850
87- 90 F4.2 mag EvB Luminosity evolution in the B band (2)
92- 95 F4.2 Gyr Age Age of the population
97-101 F5.2 [Msun] logM* Stellar mass fitting
103-107 F5.2 [Msun] logM1kpc Stellar mass within 1kpc radius
109-114 F6.2 mag BMAG Absolute B magnitude
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Note (1): Cluster names are
XMM2235 for XMM J2235-2557 (XMMXCS J223520.4-255742.1),
RDCS0848 for RDCS J0848+4453 (RDCS J0848+4453),
XLSS0223 for XLSS J0223-0436 (XLSS J022303.3-043621).
Note (2): luminosity evolution in the B band of the galaxy from its redshift
to z=0, according to its own age based on Bruzual & Charlot,
2003MNRAS.344.1000B 2003MNRAS.344.1000B) models.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 17-May-2017