J/MNRAS/422/25 SDSS DR7 groups, clusters and filaments (Smith+, 2012) ================================================================================ Multiscale probability mapping: groups, clusters and an algorithmic search for filaments in SDSS. Smith A.G., Hopkins A.M., Hunstead R.W., Pimbblet K.A. =2012MNRAS.422...25S ================================================================================ ADC_Keywords: Surveys ; Clusters, galaxy ; Morphology ; Redshifts Keywords: methods: statistical - catalogues - surveys - galaxies: clusters: general - galaxies: groups: general - large-scale structure of Universe Abstract: We have developed a multiscale structure identification algorithm for the detection of overdensities in galaxy data that identifies structures having radii within a user-defined range. Our "multiscale probability mapping" technique combines density estimation with a shape statistic to identify local peaks in the density field. This technique takes advantage of a user-defined range of scale sizes, which are used in constructing a coarse-grained map of the underlying fine-grained galaxy distribution, from which overdense structures are then identified. In this study we have compiled a catalogue of groups and clusters at 0.0250.5 (1) 49- 53 F5.1 --- LDCa ? Local density contrast (LDC) with radii [0.4,2]Mpc/h 54 A1 --- n_LDCa [i] 'i' for infinity 55- 58 F4.1 --- LDCb ? Local density contrast (LDC) with radii [1,2]Mpc/h 59 A1 --- n_LDCb [i] 'i' for infinity 60- 63 I4 km/s sigma Velocity dispersion {sigma} 65- 70 F6.1 --- Dens ?=-1 Galaxy density within 0.4Mpc/h in units of the background density -------------------------------------------------------------------------------- Note (1): * P is the overdensity probability, and P>0.5 designates a location denser than average * S is the shape statistic, and S<0.5 designates a location denser than surrounding locations * P-S>0.5 designates therefore locations denser than average and denser than surrounding locations, guaranteeing P > 0.5 and S < 0.5 -------------------------------------------------------------------------------- Byte-by-byte Description of file: table5.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 I5 --- ID [1/10443] Identification number (from central group or cluster) 7- 14 F8.4 deg RAdeg Right Ascension (J2000) (deg) 16- 22 F7.4 deg DEdeg Declination (J2000) (deg) 24- 30 F7.5 --- z Redshift 32- 36 F5.3 --- Pe Highest elongation probability within 10Mpc/h 38- 39 I2 --- N [3/15] Count of groups and clusters within a 10Mpc/h radius on the sky and 10Mpc/h in the line of sight (cylindrical aperture) 41- 42 A2 --- Mph [I II V] Morphology of the filament (1) -------------------------------------------------------------------------------- Note (1): the morphology class is based on the appearance in two orthogonal planes: the sky, and a plane perpendicular to the sky and aligned with the the filament: I = Type I (straight). Both are straight II = Type II (warped). At least one is curved, with neither being uniform or irregular V = Type IV (uniform). Both are uniform -------------------------------------------------------------------------------- Byte-by-byte Description of file: void.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 I5 --- ID Identification number (from a lattice of sampling positions formed by spectroscopic plate centres and a uniform redshift interval) 7- 14 F8.4 deg RAdeg Centre Right Ascension (J2000) 16- 22 F7.4 deg DEdeg Centre Declination (J2000) 24- 30 F7.5 --- z Centre Redshift -------------------------------------------------------------------------------- History: * 27-Nov-2012: Copied at http://www.physics.usyd.edu.au/~asmith/MSPM/ * 14-Jan-2013: In table1, first 331 lines omitted added ================================================================================ (End) Patricia Vannier [CDS] 27-Nov-2012