J/ApJ/781/2 Redshifts of 1151 galaxies from SDSS (Ammons+, 2014)
Mapping compound cosmic telescopes containing multiple projected cluster-scale
halos.
Ammons S.M., Wong K.C., Zabludoff A.I., Keeton C.R.
<Astrophys. J., 781, 2 (2014)>
=2014ApJ...781....2A 2014ApJ...781....2A (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxy catalogs ; Spectroscopy ; Redshifts ;
Photometry, SDSS
Keywords: galaxies: clusters: general - galaxies: high-redshift -
galaxies: kinematics and dynamics - gravitational lensing: strong -
techniques: radial velocities
Abstract:
Lines of sight with multiple projected cluster-scale gravitational
lenses have high total masses and complex lens plane interactions that
can boost the area of magnification, or etendue, making detection of
faint background sources more likely than elsewhere. To identify these
new "compound" cosmic telescopes, we have found directions in the sky
with the highest integrated mass densities, as traced by the projected
concentrations of luminous red galaxies (LRGs). We use new galaxy
spectroscopy to derive preliminary magnification maps for two such
lines of sight with total mass exceeding ∼3x1015M☉. From 1151
MMT Hectospec spectra of galaxies down to iAB=21.2, we identify two
to three group- and cluster-scale halos in each beam. These are well
traced by LRGs. The majority of the mass in beam J085007.6+360428
(0850) is contributed by Zwicky 1953, a massive cluster at z=0.3774,
whereas beam J130657.5+463219 (1306) is composed of three halos with
virial masses of 6x1014-2x1015M☉, one of which is A1682. The
magnification maps derived from our mass models based on spectroscopy
and Sloan Digital Sky Survey photometry alone display substantial
etendue: the 68% confidence bands on the lens plane area with
magnification exceeding 10 for a source plane of zs=10 are
[1.2,3.8]arcmin2 for 0850 and [2.3,6.7]arcmin2 for 1306. In deep
Subaru Suprime-Cam imaging of beam 0850, we serendipitously discover a
candidate multiply imaged V-dropout source at zphot=5.03. The
location of the candidate multiply imaged arcs is consistent with the
critical curves for a source plane of z=5.03 predicted by our mass
model. Incorporating the position of the candidate multiply imaged
galaxy as a constraint on the critical curve location in 0850 narrows
the 68% confidence band on the lens plane area with µ>10 and
zs=10 to [1.8,4.2]arcmin2, an etendue range comparable to that of
MACS 0717+3745 and El Gordo, two of the most powerful single cluster
lenses known. The significant lensing power of our beams makes them
powerful probes of reionization and galaxy formation in the early
universe.
Description:
We selected the two beams J085007.6+360428 (0850) and J130657.5+463219
(1306) from the SDSS DR9 (cat. V/139) for their high total luminosity
densities of Luminous Red Galaxies (LRGs). These two beams were
originally selected from an earlier version of our list of beams based
on the Padmanabhan et al. (2007MNRAS.378..852P 2007MNRAS.378..852P) LRG catalog, and they
are both within the top 200 beams presented by Wong et al. 2013 (cat.
J/ApJ/769/52). The basic properties of the two beams are presented in
Table1.
We completed a redshift survey of 1151 field galaxies in the two beams
with the 6.5m MMT telescope on Mt. Hopkins (Arizona) and the
Hectospec, a multi-object optical spectrograph with 300 fibers
accessing a 1° field of view.
Hectospec's grating with 270 grooves/mm delivers a spectral resolution
of ∼4.5-5.2Å (R∼750-1800) and a spectral coverage of 3650-9200Å
with a central wavelength of 6500Å. This wavelength coverage is
selected to include [OII]λ3726 and λ3729 emission lines,
CaIIHλ3968 and Kλ3934 absorption, and Hβ lines for
galaxies in the range 0<z<0.7.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 83 2 Beam properties
table2.dat 45 1151 Spectroscopic data
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See also:
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
VII/110 : Rich Clusters of Galaxies (Abell+ 1989)
VII/190 : Zwicky Galaxy Catalog (Zwicky+ 1968)
J/ApJ/769/52 : SDSS luminous red galaxies concentrations (Wong+, 2013)
J/ApJS/199/34 : Clusters of galaxies in SDSS-III (Wen+, 2012)
J/A+A/535/A4 : X-ray galaxy clusters study (Reichert+, 2011)
J/ApJS/191/254 : GMBCG galaxy cluster catalog from SDSS DR7 (Hao+, 2010)
J/ApJS/183/197 : Galaxy clusters identified from the SDSS-DR6 (Wen+, 2009)
J/ApJS/182/12 : ICM entropy profiles (ACCEPT) (Cavagnolo+, 2009)
J/ApJS/174/117 : Properties and metal abundances of clusters (Maughan+, 2008)
J/ApJ/682/821 : Spectral fits of galaxy clusters in X-ray (Cavagnolo+, 2008)
J/ApJ/660/239 : MaxBCG catalog of 13823 SDSS galaxy clusters (Koester+, 2007)
J/AJ/125/2064 : Northern Optical Cluster Survey. II. (Gal+, 2003)
J/ApJS/129/435 : NORAS galaxy cluster survey. I. (Bohringer+, 2000)
J/MNRAS/306/857 : ROSAT Brightest Cluster Sample. III. (Crawford+, 1999)
J/MNRAS/301/881 : The ROSAT brightest cluster sample - I. (Ebeling+, 1998)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- Name Short beam name (HHMM format) (1)
6- 7 I2 h RAh Hour of Right Ascension (J2000) (2)
9- 10 I2 min RAm Minute of Right Ascension (J2000) (2)
12- 16 F5.2 s RAs Second of Right Ascension (J2000) (2)
18 A1 --- DE- Sign of the Declination (J2000) (2)
19- 20 I2 deg DEd Degree of Declination (J2000) (2)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000) (2)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000) (2)
30- 32 F3.1 10+37W LX X-ray luminosity (in 1044erg/s) (3)
34- 36 F3.1 10+11Lsun Llrg Total Luminous Red Galaxy (LRG) luminosity (2)
38- 39 I2 --- Nlrg Number of LRGs (2)
41- 83 A43 --- Cluster Most massive cluster (4)
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Note (1): We selected the two beams J085007.6+360428 (0850) and J130657.5+463219
(1306) from the SDSS DR9 (cat. V/139) for their high total luminosity
densities of Luminous Red Galaxies (LRGs). These two beams were originally
selected from an earlier version of our list of beams based on the
Padmanabhan et al. (2007MNRAS.378..852P 2007MNRAS.378..852P) LRG catalog, and they are both
within the top 200 beams presented by Wong et al. 2013 (cat. J/ApJ/769/52).
Note (2): Given as the coordinates of the Luminous Red Galaxy (LRG) on which the
3.5' radius circle used to count LRGs is centered. Total LRG luminosities,
numbers of LRGs, and beam centroids are taken from Wong et al. 2013
(cat. J/ApJ/769/52).
Note (3): In the 0.1-2.4keV band, expressed in the rest frame of the most
massive cluster. X-ray luminosity is from Ebeling et al. 1998
(cat. J/MNRAS/301/881).
Note (4): References for cluster redshifts are Zwicky et al. 1961 (cat. VII/190)
and Abell et al. 1989 (cat. VII/110).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 h RAh Hour of Right Ascension (J2000) (1)
4- 5 I2 min RAm Minute of Right Ascension (J2000) (1)
7- 11 F5.2 s RAs Second of Right Ascension (J2000) (1)
13 A1 --- DE- Sign of the Declination (J2000) (1)
14- 15 I2 deg DEd Degree of Declination (J2000) (1)
17- 18 I2 arcmin DEm Arcminute of Declination (J2000) (1)
20- 23 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
25- 31 F7.5 --- z [0/1] Heliocentric redshift (1)
33- 39 F7.5 --- e_z Error in z (1)
41- 45 F5.2 mag imag [14.4/22] SDSS AB i-band magnitude (1)
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Note (1): For all galaxies with a secure, visually confirmed assigned redshift.
We present 596 reshift success spectra satisfying 0.01<z<1.0 in beam 0850
(J085007.6+360428) and 555 redshift success spectra satisfying 0.01<z<1.0
in beam 1306 (J130657.5+463219).
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 09-Nov-2015