J/ApJ/837/16 Cosmic web of galaxies in the COSMOS field (Darvish+, 2017)
Cosmic web of galaxies in the COSMOS field: public catalog and different
quenching for centrals and satellites.
Darvish B., Mobasher B., Martin D.C., Sobral D., Scoville N., Stroe A.,
Hemmati S., Kartaltepe J.
<Astrophys. J., 837, 16-16 (2017)>
=2017ApJ...837...16D 2017ApJ...837...16D (SIMBAD/NED BibCode)
ADC_Keywords: Galaxy catalogs ; Redshifts
Keywords: galaxies: evolution; galaxies: high-redshift;
large-scale structure of universe
Abstract:
We use a mass complete (log(M/M☉)≥9.6) sample of galaxies with
accurate photometric redshifts in the COSMOS field to construct the
density field and the cosmic web to z=1.2. The comic web extraction
relies on the density field Hessian matrix and breaks the density
field into clusters, filaments, and the field. We provide the density
field and cosmic web measures to the community. We show that at
z≲0.8, the median star formation rate (SFR) in the cosmic web
gradually declines from the field to clusters and this decline is
especially sharp for satellites (∼1dex versus ∼0.5dex for centrals).
However, at z≳0.8, the trend flattens out for the overall galaxy
population and satellites. For star-forming (SF) galaxies only, the
median SFR is constant at z≳0.5 but declines by ∼0.3-0.4dex from the
field to clusters for satellites and centrals at z≲0.5. We argue that
for satellites, the main role of the cosmic web environment is to
control their SF fraction, whereas for centrals, it is mainly to
control their overall SFR at z≲0.5 and to set their fraction at
z≳0.5. We suggest that most satellites experience a rapid quenching
mechanism as they fall from the field into clusters through filaments,
whereas centrals mostly undergo a slow environmental quenching at
z≲0.5 and a fast mechanism at higher redshifts. Our preliminary
results highlight the importance of the large-scale cosmic web on
galaxy evolution.
Description:
Here, we use the latest COSMOS2015 photometric redshift (photo-z)
catalog (Laigle+ 2016, J/ApJS/224/24) in the UltraVISTA-DR2 region
(McCracken+ 2012, J/A+A/544/A156; Ilbert+ 2013, J/A+A/556/A55). This
comprises ground- and space-based photometric data in more than 30
bands.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 93 45421 Sample galaxies with estimated density values,
cosmic web environments, and galaxy type
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See also:
VII/86 : Groups of Galaxies. I. Nearby Groups (Huchra+ 1982)
II/284 : COSMOS Multi-Wavelength Photometry Catalog (Capak+, 2007)
VII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)
J/ApJS/172/182 : XMM Clusters of galaxies in COSMOS field (Finoguenov+ 2007)
J/ApJ/690/1236 : COSMOS photometric redshift catalog (Ilbert+, 2009)
J/ApJS/184/218 : The zCOSMOS 10k-bright spectroscopic sample (Lilly+, 2009)
J/A+A/544/A156 : UltraVISTA Catalogue Release DR1 (McCracken+, 2012)
J/MNRAS/422/25 : SDSS DR7 groups, clusters and filaments (Smith+, 2012)
J/A+A/556/A55 : Multi-color photom. of star-forming galaxies (Ilbert+, 2013)
J/ApJS/206/8 : COSMOS/UltraVISTA Ks-selected catalogs v4.1 (Muzzin+, 2013)
J/MNRAS/440/843 : SIM2D parameters of SDSS-DR7 galaxies (Omand+, 2014)
J/MNRAS/438/3465 : Cosmic web filaments in the SDSS (Tempel+, 2014)
J/ApJ/805/121 : Overdensities of 0<z<3 COSMOS galaxies (Darvish+, 2015)
J/MNRAS/450/630 : MC2: SFR in CIZA J2242.8+5301 (Sobral+, 2015)
J/MNRAS/458/3443 : Cl0939+4713 Hα z∼0.4 star-forming gal. (Sobral+ 2016)
J/ApJ/833/178 : GLASS. VII. Hα maps (Vulcani+, 2016)
J/ApJS/224/24 : The COSMOS2015 catalog (Laigle+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- COSMOS2015 Original sequence number in Laigle+ 2016,
J/ApJS/224/24
8- 17 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000)
19- 26 F8.6 deg DEdeg Declination in decimal degrees (J2000)
28- 33 F6.4 --- zph [0.1/1.2] Photometric redshift
35- 39 F5.2 Mpc-2 Den [0.01/93] Density
41- 45 F5.2 --- Oden [0/37.3] Density divided by the median density
at each redshift
47- 54 F8.6 --- SCl [0/0.9] Cluster signal, resemblance of the
local geometry to a cluster
56- 63 F8.6 --- SFil [0/0.9] Filament signal, resemblance of the
local geometry to a filament
65- 72 A8 --- CWE Cosmic Web Environment (1)
74- 77 I4 --- Group [1/7231]?=-99 Group ID (2)
79- 81 I3 --- Ngroup [2/377]?=-99 Number of members in Group
83- 91 A9 --- Type Galaxy type ("satellite" (21316 occurrences),
"isolated" (16874 occurrences) or "central")
93- 93 I1 --- Flag Flag (1=Objects that are close to the edge
or masked area; not used for the analysis)
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Note (1): "cluster" (4926 occurrences), "filament" (17902 occurrences) or
"field" (22593 occurrences)); see Section 3.4.
The median density of our sample galaxies in clusters, filaments, and
the field is 8.61, 3.09, and 1.53Mpc-2, respectively.
Note (2): We select the most massive galaxy in each group as a central and the
rest as satellites. Galaxies that are not associated with any galaxy
group (isolated) are either centrals whose satellites, in principle,
are too faint to be detected in our volume-limited sample or they are
ejected satellites orbiting beyond their halo's virial radius. We rely
on our sample galaxies (our volume-limited-like sample) to identify
groups. See section 3.5.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 10-Oct-2017