Table information for 'mdr1.FOF'


Table Description: Friends-of-Friends halo catalogue, level 0 with relative linking length 0.17

This table is available for ADQL queries and through the TAP endpoint.

Resource Description: This is an extract of the MultiDark Run 1 simulation data. It is used for testing and demonstration purposes only. The full data is available at

For a list of all services and tables belonging to this table's resource, see Information on resource 'MDR1 - MultiDark Run 1'

Resource Reference URL: MDR1

Citing this table

To cite the table as such, we suggest the following BibTeX entry:

  title={{MDR1} - {MultiDark} Run 1},
  author={Riebe K.},
  howpublished={{VO} resource provided by the {AIP} {DaCHS}}

Resource Documentation

Extensive documentation is available at See also: Riebe et al. 2013, The MultiDark Database, AN 334, 691, for a description of its predecessor


Sorted by DB column index. [Sort alphabetically]

NameTable Head DescriptionUnitUCD
fofId fofId unique id for FOF-group N/A;meta.main
snapnum snapnum number of snapshot; look into redshifts-table to find the corresponding redshift N/A time.epoch
level level level of substructure, indicates the different linking lengths N/A N/A
NInFile NInFile line number of FOF-group in original catalogue file (= rank in file) N/A
x x comoving position, x-component h-1.Mpc pos.cartesian.x
y y comoving position, y-component h-1.Mpc pos.cartesian.y
z z comoving position, z-component h-1.Mpc pos.cartesian.z
vx vx peculiar velocity, x-component km/s phys.veloc;pos.cartesian.x
vy vy peculiar velocity, y-component km/s phys.veloc;pos.cartesian.y
vz vz peculiar velocity, z-component km/s phys.veloc;pos.cartesian.z
np np number of particles inside the FOF group ('halo') N/A meta.number
mass mass total mass of the FOF group h-1.solMass phys.mass
size size 'radius' of the FOF group, if it were a sphere, computed based on the volume h-1.Mpc phys.size.radius
disp disp dispersion h-1.Mpc phys.dispMeasure
disp_v disp_v velocity dispersion km/s phys.veloc.dispersion
delta delta overdensity (mass/volume) in terms of mean background density rho_b N/A phys.density;arith.ratio
spin spin spin parameter (Gottloeber and Yepes 2007, ApJ 664, 117) N/A N/A
angMom_x angMom_x angular momentum, x-component phys.angMomentum;pos.cartesian.x
angMom_y angMom_y angular momentum, y-component phys.angMomentum;pos.cartesian.y
angMom_z angMom_z angular momentum, z-component phys.angMomentum;pos.cartesian.z
angMom angMom absolute value of angular momentum phys.angMomentum
axis1 axis1 major axis of the ellipsoidal shape, not normalized N/A N/A
axis2 axis2 intermediate axis of the ellipsoidal shape, not normalized N/A N/A
axis3 axis3 minor axis of the ellipsoidal shape, not normalized N/A N/A
axis1_x axis1_x direction of major axis, unit eigenvector of the inertia tensor, x-component N/A N/A
axis1_y axis1_y direction of major axis, y-component N/A N/A
axis1_z axis1_z direction of major axis, z-component N/A N/A
axis2_x axis2_x direction of intermediate axis, unit eigenvector of the inertia tensor, x-component N/A N/A
axis2_y axis2_y direction of intermediate axis, y-component N/A N/A
axis2_z axis2_z direction of intermediate axis, z-component N/A N/A
axis3_x axis3_x direction of minor axis, unit eigenvector of the inertia tensor, x-component N/A N/A
axis3_y axis3_y direction of minor axis, y-component N/A N/A
axis3_z axis3_z direction of minor axis, z-component N/A N/A
ix ix spatial index, x-direction N/A pos.cartesian.x
iy iy spatial index, y-direction N/A pos.cartesian.y
iz iz spatial index, z-direction N/A pos.cartesian.z
phkey phkey Peano-Hilbert key N/A N/A

Columns that are parts of indices are marked like this.


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