J/MNRAS/344/602 Shape statistics of SDSS superclusters (Basilakos, 2003)
Shape statistics of Sloan Digital Sky Survey superclusters.
Basilakos S.
<Mon. Not. R. Astron. Soc. 344, 602 (2003)>
=2003MNRAS.344..602B 2003MNRAS.344..602B
ADC_Keywords: Clusters, galaxy ; Morphology
Keywords: galaxies: clusters: general - cosmology: theory -
large-scale structure of Universe
Abstract:
We study the supercluster shape properties of the recently compiled
Sloan Digital Sky Survey (SDSS) cluster catalogue using an approach
based on differential geometry. We detect superclusters by applying
the percolation algorithm to observed cluster populations, extended
out to zmax≤0.23 in order to avoid selection biases. We utilize a
set of shapefinders in order to study the morphological features of
superclusters with ≥8 cluster members and find that filamentary
morphology is the dominant supercluster shape feature, in agreement
with previous studies.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 75 57 List of the SDSS superclusters using
Rpr=26h-1Mpc.
--------------------------------------------------------------------------------
See also:
J/AJ/123/1807 : SDSS galaxy clusters redshifts (Goto+, 2002)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 3 I2 --- [B2003] Index
5- 6 I2 --- K Multiplicity (1)
9- 14 F6.2 Mpc alpha1 alpha1 (semi-major) axis, in h-1Mpc (1)
17- 21 F5.2 Mpc alpha2 alpha2 axis, in h-1Mpc (1)
24- 28 F5.2 Mpc alpha3 alpha3 axis, in h-1Mpc (1)
31- 35 F5.3 --- z Redshift
38- 43 F6.2 deg RAdeg Supercluster center Right ascension in
decimal degrees (J2000)
45- 50 F6.2 deg DEdeg Supercluster center Declination in
decimal degrees (J2000)
53- 57 F5.3 --- K1 Shapefinder K1 (2)
60- 64 F5.3 --- K2 Shapefinder K2 (2)
67- 70 F4.2 --- R K1/K2 ratio
72- 76 A5 --- Type Morphological classification type (3)
--------------------------------------------------------------------------------
Note (1): Eigenvalues directly related to the three principal axes of
the fitted ellipsoid
Note (2): Shapefinders are defined as
K1=(H2-H1)/(H2+H1) and K2=(H3-H2)/(H3+H2) where
H1=V/S, H2 =S/C and H3=C with
S being the surface area,
C being the integrated mean curvature,
and V the volume of the fitted ellipsoid.
Note (3): Morphological classification type:
F denotes filaments,
P denotes pancakes and
cT denotes close to triaxial.
B means that the specific entry is close to the boundaries of the
SDSS cluster catalogue.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 24-Oct-2003