J/MNRAS/438/3465 Cosmic web filaments in the SDSS (Tempel+, 2014)
Detecting filamentary pattern in the cosmic web: a catalogue of filaments for
the SDSS.
Tempel E., Stoica R.S., Martinez V.J., Liivamagi L.J., Castellan G., Saar E.
<Mon. Not. R. Astron. Soc. 438, 3465 (2014)>
=2014MNRAS.438.3465T 2014MNRAS.438.3465T
ADC_Keywords: Galaxy catalogs ; Galaxies, photometry ; Clusters, galaxy
Keywords: methods: data analysis - methods: statistical - catalogues -
galaxies: statistics - large-scale structure of Universe
Abstract:
The main feature of the spatial large-scale galaxy distribution is its
intricate network of galaxy filaments. This network is spanned by the
galaxy locations that can be interpreted as a three-dimensional point
distribution. The global properties of the point process can be
measured by different statistical methods, which, however, do not
describe directly the structure elements. The morphology of the large
scale structure, on the other hand, is an important property of the
galaxy distribution. Here we apply an object point process with
interactions (the Bisous model) to trace and extract the filamentary
network in the presently largest galaxy redshift survey, the Sloan
Digital Sky Survey (SDSS). We search for filaments in the galaxy
distribution that have a radius of about 0.5Mpc/h. We divide the
detected network into single filaments and present a public catalogue
of filaments. We study the filament length distribution and show that
the longest filaments reach the length of 60Mpc/h. The filaments
contain 35-40% of the total galaxy luminosity and they cover roughly
5-8% of the total volume, in good agreement with N-body simulations
and previous observational results.
Description:
Filament main parameters for 15421 filaments found from SDSS data
using Bisous model. For each filament we give points containing
position, direction and some additional parameters measured in each
point. Tables include also galaxies that filaments contain. The
cosmology assumes Ho=100km/s/Mpc, Ωm=0.7, ΩΛ=0.73.
The tables are also available at http://www.aai.ee/~elmo/sdss-filaments
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 99 15421 Filament properties
table2.dat 117 275599 Filament points properties
table3.dat 147 576493 Galaxies that filament contains
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See also:
II/306 : SDSS Photometric Catalog, Release 8 (Adelman-McCarthy+, 2011)
J/A+A/540/A106 : SDSS-DR8 groups and clusters of galaxies (Tempel+, 2012)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ID [1/15421] Unique identification number for a
filament
7- 9 I3 --- Npts [5/128] Number of points in the filament (1)
11- 18 F8.5 Mpc Len Filament length in Mpc/h (2)
20- 22 I3 --- Ng.5 [2/234] Number of galaxies closer than
0.5Mpc/h to filament axis
24- 26 I3 --- Ng1 [2/429] Number of galaxies closer than
1.0Mpc/h to filament axis
28- 36 F9.5 10+10Lsun L0.5 Luminosity of filament up to 0.5Mpc/h (3)
38- 46 F9.5 10+10Lsun L1.0 Luminosity of filament up to 1.0Mpc/h (3)
48- 56 F9.4 Mpc xmin Filament minimum coordinate in x axis (Mpc/h)
58- 65 F8.4 Mpc ymin Filament minimum coordinate in y axis (Mpc/h)
67- 75 F9.4 Mpc zmin Filament minimum coordinate in z axis (Mpc/h)
77- 83 F7.4 Mpc xlen Filament range in x axis (Mpc/h)
85- 91 F7.4 Mpc ylen Filament range in y axis (Mpc/h)
93- 99 F7.4 Mpc zlen Filament range in z axis (Mpc/h)
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Note (1): spacing of filament points is 0.5Mpc/h (Ho=100km/s/Mpc)
Note (2): measured along the filament from point to point (Ho=100km/s/Mpc)
Note (3): sum of luminosities of observed galaxies in units of
1010L☉/h2 (Ho=100km/s/Mpc)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ID [1/15421] Filament identification number
7- 12 I6 --- IDpt [1/275599] Unique identification number for
a filament point, shared for all filaments
14- 16 I3 --- Npts [5/128] Number of filament points in the
filament the point belongs to
18- 25 F8.5 Mpc Len Length of the filament the point belongs
to (Mpc/h)
27- 35 F9.4 Mpc x Co-moving coordinate of the point (Mpc/h)
37- 45 F9.4 Mpc y Co-moving coordinate of the point (Mpc/h)
47- 55 F9.4 Mpc z Co-moving coordinate of the point (Mpc/h)
57- 66 F10.5 Mpc D Distance to filament point (Mpc/h)
68- 75 F8.5 Mpc dx [-1/1] Orientation of filament point (Mpc/h) (1)
77- 84 F8.5 Mpc dy [-1/1] Orientation of filament point (Mpc/h) (1)
86- 93 F8.5 Mpc dz [-1/1] Orientation of filament point (Mpc/h) (1)
95-101 F7.5 --- vmap [0/1] Visit map (level set) value
103-109 F7.5 --- fden [0/1] Weighted visit map value
111-117 F7.5 --- fori [0/1] Strength of orientation
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Note (1): unit vector, i.e. dx2+dy2+dz2=1
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- IDgal [1/576493] Unique identification number for
a galaxy (1)
8- 10 I3 --- Ngal [1/878] Richness of the group the galaxy
belongs to
12- 19 F8.6 --- z [0.009/0.2] Redshift (2)
21- 30 F10.6 deg RAdeg Right ascension (J2000)
32- 41 F10.6 deg DEdeg Declination (J2000)
43- 52 F10.6 Mpc Dcor Co-moving distance of the galaxy when the
finger-of-god effect is suppressed (Mpc/h)
54- 61 F8.5 mag umag Petrosian u magnitude (3)
63- 70 F8.5 mag gmag Petrosian g magnitude (3)
72- 79 F8.5 mag rmag Petrosian r magnitude (3)
81- 88 F8.5 mag imag Petrosian i magnitude (3)
90- 97 F8.5 mag zmag ? Petrosian z magnitude (3)
99-110 F12.9 10+10Lsun Lr Absolute luminosity in r-band (4)
112-116 F5.3 --- w [1/9] Weight factor for the galaxy
118-125 F8.4 Mpc Dedg Co-moving distance of the galaxy from the
border of the survey mask (Mpc/h)
127-134 F8.5 Mpc Dfil Distance from nearest filament axis (Mpc/h)
136-140 I5 --- ID [0/15421]?=0 ID of nearest filament
142-147 I6 --- IDpt [0/275599]?=0 ID of the nearest filament point
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Note (1): as used in Tempel et al. (2012, Cat. J/A+A/540/A106).
Note (2): corrected to the CMB rest frame.
Note (3): corrected by Galactic extinction.
Note (4): unit is 1010L☉/h2 and M☉ is taken 4.64mag.
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Acknowledgements:
Elmo Tempel, elmo.tempel (at) to.ee
(End) Elmo Tempel [Tartu Obs., Estonia], Patricia Vannier [CDS] 14-Jan-2014