J/ApJ/902/17 Spectroscopy of quiescent gal. in 9 lensing clusters (Sohn+, 2020)
The velocity dispersion function for quiescent galaxies in nine strong-lensing
clusters.
Sohn J., Fabricant D.G., Geller M.J., Hwang Ho S., Diaferio A.
<Astrophys. J., 902, 17 (2020)>
=2020ApJ...902...17S 2020ApJ...902...17S
ADC_Keywords: Clusters, galaxy; Redshifts; Galaxies, spectra; Optical;
Velocity dispersion; Magnitudes, absolute; Photometry, SDSS
Keywords: Early-type galaxies ; Galaxy clusters ; Luminosity function ;
Galaxy mass distribution ; Redshift surveys
Abstract:
We measure the central stellar velocity dispersion function for
quiescent galaxies in a set of nine northern clusters in the redshift
range 0.18<z<0.29 and with strong lensing arcs in Hubble Space
Telescope images. The velocity dispersion function links galaxies
directly to their dark matter halos. From dense SDSS and MMT/Hectospec
spectroscopy, we identify 222-463 spectroscopic members in each
cluster. We derive physical properties of cluster members including
redshift, Dn4000, and central stellar velocity dispersion and we
include a table of these measurements for 3419 cluster members. We
construct the velocity dispersion functions for quiescent galaxies
with Dn4000>1.5 and within R200. The cluster velocity dispersion
functions all show excesses at σ≳250km/s compared to the field
velocity dispersion function. The velocity dispersion function slope
at large velocity dispersion (σ>160km/s) is steeper for more
massive clusters, consistent with the trend observed for cluster
luminosity functions. The spatial distribution of galaxies with large
velocity dispersion at radii larger than R200 further underscores the
probable major role of dry mergers in the growth of massive cluster
galaxies during cluster assembly.
Description:
We examine the galaxy velocity dispersion functions of nine clusters
with 0.18<z<0.28. As of 2015, this sample included all northern strong
lensing clusters in this redshift range with Hubble Space Telescope
(HST) imaging.
We compile previous spectroscopic data obtained with three
instruments: SDSS, BOSS, and MMT/Hectospec.
We obtain the SDSS and BOSS data from SDSS DR14.
We compile Hectospec data from two previous surveys: Hectospec Cluster
Surveys (HeCS; e.g. Rines+ 2013, J/ApJ/767/15) and the Arizona Cluster
Redshift Survey (ACReS; e.g. Haines+ 2015ApJ...806..101H 2015ApJ...806..101H).
We carried out additional Hectospec observations for all of the target
clusters between 2011 and 2017.
The resulting Hectospec spectra cover 3750-9100Å at R∼1000; SDSS
spectra cover 3800-9200Å at R∼2000; and BOSS spectra cover
3560-10400Å also at R∼2000.
Throughout the paper, we adopt a ΛCDM cosmology with
H0=70km/s/Mpc, Ωm=0.3, and ΩΛ=0.7.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 73 9 The cluster sample
table2.dat 98 1614 Spectroscopic members
--------------------------------------------------------------------------------
See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
J/ApJ/496/39 : Properties of poor groups of galaxies. I. (Zabludoff+ 1998)
J/ApJ/591/764 : R mag for 6 nearby galaxy clusters (Christlein+, 2003)
J/AJ/132/1275 : CIRS (Cluster Infall Regions in the SDSS). I. (Rines+, 2006)
J/ApJ/671/1503 : Cl 0024+16 and MS 0451-03 spectrophotometry (Moran+, 2007)
J/MNRAS/407/2207 : Group of early-type galaxies (Fraix-Burnet+, 2010)
J/MNRAS/432/3141 : Morphological classif. of PM2GC galaxies (Calvi+, 2013)
J/ApJ/767/15 : Hectospec Cluster Survey (HeCS) (Rines+, 2013)
J/ApJ/783/52 : Redshifts in the field of A383 (Geller+, 2014)
J/ApJ/797/106 : Redshifts in nine galaxy cluster fields (Hwang+, 2014)
J/ApJ/797/82 : Brightest cluster galaxies in Abell clusters (Lauer+, 2014)
J/ApJ/819/63 : Hectospec survey of SZ clusters (HeCS-SZ) (Rines+, 2016)
J/ApJS/229/20 : MMT/Hectospec redshift survey for Abell 2029 (Sohn+, 2017)
J/ApJ/862/172 : Hectospec surveys of redMaPPer clusters (Rines+, 2018)
J/ApJ/871/129 : A redshift catalog of the galaxy cluster A2029 (Sohn+, 2019)
J/ApJ/872/192 : A spectroscopic census of A2029 members (Sohn+, 2019)
J/ApJ/891/129 : The HeCS-omnibus catalog: SDSS & MMT sp. obs. (Sohn+, 2020)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Cluster Cluster name
9- 18 F10.6 deg RAdeg [9.26/328.4] Right ascension (J2000)
20- 28 F9.6 deg DEdeg [-3.53/51.83] Declination (J2000)
30- 36 F7.5 --- z [0.184/0.288] Redshift
38- 40 I3 --- Nm [222/463] Number of spectroscopically
identified members
42- 44 I3 --- N200 [117/266] Number of spectroscopic members
within R200
46- 48 I3 --- N200Q [92/217] Number of quiescent members
(Dn4000>1.5) within R200
50- 52 I3 --- N200Qs [89/207] Number of quiescent members with a
central stellar velocity dispersion
measurement
54- 57 F4.2 Mpc R200 [1.65/2.34] Radius that contains a mean
density 200 times larger than the critical
density of the universe
59- 62 F4.2 Mpc e_R200 [0.01/0.21] R200 uncertainty
64- 68 F5.2 10+14Msun M200 [6.15/18.42] Mass enclosed within R200
70- 73 F4.2 10+14Msun e_M200 [0.16/4.2] M200 uncertainty
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Cluster Name of the cluster
9- 27 I19 --- objID SDSS DR14 object ID of the galaxy member
29- 38 F10.6 deg RAdeg [9.14/328.6] Right Ascension (J2000)
40- 48 F9.6 deg DEdeg [-3.63/52] Declination (J2000)
50- 55 F6.4 --- zspec [0.1745/0.2975] Spectroscopic redshift
57- 62 F6.4 --- e_zspec [0.0001/0.0007] Spectroscopic redshift error
64- 69 F6.2 mag rMAG [-24.65/-18.52] r-band absolute magnitude
71- 76 F6.2 mag rmag [15.82/21.47]?=-99 r-band apparent magnitude
78- 83 F6.2 --- Dn4000 [0.38/2.93]?=-99 Dn4000 spectral index (1)
85- 90 F6.2 --- e_Dn4000 [0.01/0.9]?=-99 Uncertainty in Dn4000
92- 94 I3 km/s sigma [31/806]?=-99 Velocity Dispersion (2)
96- 98 I3 km/s e_sigma [6/582]?=-99 Uncertainty in sigma
--------------------------------------------------------------------------------
Note (1): Dn4000 is the flux ratio between 3850-3950Å and 4000-4100Å.
See also Balogh+ (1999ApJ...527...54B 1999ApJ...527...54B); Fabricant+ (2008PASP..120.1222F 2008PASP..120.1222F).
Note (2): Velocity dispersion within a rest-frame 3kpc aperture.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 19-Jan-2022