J/A+A/568/A46 High redshift cosmic web with quasar systems (Einasto+, 2014)
Tracing a high redshift cosmic web with quasar systems.
Einasto M., Tago E., Lietzen H., Park C., Heinamaki P., Saar E., Song H.,
Liivamaki L.J., Einasto J.
<Astron. Astrophys. 568, A46 (2014)>
=2014A&A...568A..46E 2014A&A...568A..46E
ADC_Keywords: QSOs ; Redshifts ; Photometry, SDSS
Keywords: cosmology: large-scale structure of the Universe - quasars: general
Abstract:
To understand the formation, evolution, and present-day properties of
the cosmic web we need to study it at low and high redshifts. We trace
the cosmic web at redshifts 1.0<z<1.8 using the quasar (QSO) data from
in the SDSS DR7 QSO catalogue. We apply a friend-of-friend (FoF)
algorithm to the quasar and random catalogues to determine systems at
a series of linking length, and analyse richness and sizes of these
systems. At the linking lengths l≤30Mpc/h, the number of quasar
systems is larger than the number of systems detected in random
catalogues, and the systems themselves have smaller diameters than
random systems. The diameters of quasar systems are comparable to the
sizes of poor galaxy superclusters in the local Universe. The richest
quasar systems have four members. The mean space density of quasar
systems is close to the mean space density of local rich
superclusters. At intermediate linking lengths (40≤l≤70Mpc/h), the
richness and length of quasar systems are similar to those derived
from random catalogues. Quasar system diameters are similar to the
sizes of rich superclusters and supercluster chains in the local
Universe. The percolating system, which penetrate the whole sample
volume appears in a quasar sample at a smaller linking length than in
random samples (85Mpc/h). At the linking length 70Mpc/h, the richest
systems of quasars have diameters exceeding 500Mpc. Quasar
luminosities in systems are not correlated with the system richness.
Quasar system catalogues in our web pages and at the Strasbourg
Astronomical Data Center (CDS) serve as a database for searching for
superclusters of galaxies and for tracing the cosmic web at high
redshifts.
Description:
We present quasar system catalogues based on SDSS DR7 QSO catalogue
(Schneider et al., 2010AJ....139.2360S 2010AJ....139.2360S, Cat. VII/260)
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
qso20all.dat 136 1207 Quasar table in systems at linking length 20Mpc
qso30all.dat 136 3348 Quasar table in systems at linking length 30Mpc
qso40all.dat 136 6516 Quasar table in systems at linking length 40Mpc
qso50all.dat 136 10543 Quasar table in systems at linking length 50Mpc
qso60all.dat 136 14450 Quasar table in systems at linking length 60Mpc
qso70all.dat 136 17864 Quasar table in systems at linking length 70Mpc
qso80all.dat 136 22381 Quasar table in systems at linking length 80Mpc
qso20fof.dat 80 593 Quasar system table at linking length 20Mpc
qso30fof.dat 80 1590 Quasar system table at linking length 30Mpc
qso40fof.dat 80 2852 Quasar system table at linking length 40Mpc
qso50fof.dat 80 4064 Quasar system table at linking length 50Mpc
qso60fof.dat 80 4536 Quasar system table at linking length 60Mpc
qso70fof.dat 80 3885 Quasar system table at linking length 70Mpc
qso80fof.dat 80 2222 Quasar system table at linking length 80Mpc
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See also:
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
J/A+AS/123/119 : The supercluster-void network. I. (Einasto+ 1997)
J/A+A/540/A123 : Galaxy clusters from SDSS DR8 (Einasto+, 2012)
J/A+A/542/A36 : Rich clusters from SDSS DR8 (Einasto+, 2012)
J/A+A/566/A1 : Flux- & volume-limited groups for SDSS galaxies (Tempel+ 2014)
Byte-by-byte Description of file: qso??all.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- IDqso [61/25011] ID of quasar (our list number)
7- 10 I4 --- IDsys [0/4536] ID of quasar system
12- 14 I3 --- Nqso [1/920] Number of quasars in the system
16- 25 F10.6 deg RAdeg Right ascension of a quasar (J2000)
27- 42 F16.12 deg DEdeg Declination of a quasar (J2000)
44- 60 F17.13 deg lambda [-55/55] SDSS Survey coordinate of a quasar
62- 76 F15.11 deg eta [-33/35] SDSS Survey coordinate of a quasar
78- 87 F10.8 --- zqso [1/1.8] Redshift of a quasar
89- 98 F10.7 mag imag i-magnitude of quasar
100-117 I18 --- Best SDSS-DR7 BestObjID
119-136 I18 --- Spec SDSS-DR7 SpecObjID
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Byte-by-byte Description of file: qso??fof.dat
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Bytes Format Units Label Explanations
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1- 7 I7 --- IDsys [1/4536] ID of quasar system
8- 14 I7 --- Nqso [2/920] Number of quasars in the system
15- 26 F12.6 deg RAdeg Right ascension of the system centre (J2000)
27- 38 F12.6 deg DEdeg Declination of the system centre (J2000)
39- 50 F12.6 deg lambda SDSS Survey coordinate of the system centre
51- 62 F12.6 deg eta SDSS Survey coordinate of the system centre
63- 71 F9.1 Mpc Dist Co-moving distance of a system centre (1)
72- 80 F9.1 Mpc Diam [1/2067] Diameter of a system (1)
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Note (1): Distances in Mpc/h, where the cosmological parameters are:
h=H0/100, Ωm=0.27, ΩΛ=0.73.
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Acknowledgements:
Maret Einasto, maret.einasto(at)to.ee
History:
* 12-Aug-2014: on-line version
* 13-Oct-2014: corrected qso*all.dat files (from author)
(End) Maret Einasto [Tartu Obs., Estonia], Patricia Vannier [CDS] 03-Jul-2014