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-Introduction
-Parameters
-References

Page 2
-Introduction
-Simulation Parameters
-Reading Routines
-Dark Matter Distributions
-Halo Catalogues
-Galaxy Catalogues
-MARK III & Mock MARK III Catalogues
-Test Void Population Catalogues

Page 3
-Images

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Constrained Realization Data

The constrained simulations of the Local Universe consist mainly of three types of data:

(1) the snapshots giving the positions (and velocities) of the DM particles as obtained after the collisionless runs
(2) the halo catalogues wich list the properties of the haloes constructed with the FOF groupfinding algorithm
(3) the semi-analytic (photometric and baryonic) properties of the simulated galaxies.
Here, we briefly describe the generation and the contents of the files. The formats and units of the data are given in the codes (both F90 and IDL) provided in the reading routines section.

Please note that so far, data are given at z=0 only. Also, for the purpose of speeding up the download of the large files containing the distribution of the dark matter particles, we only provide the DM distribution randomly sampled at a 10% rate.

Finally, all data given here refer to the high resolution zone of the simulations.

Snapshots of Dark Matter: they provide with the positions and peculiar velocities of the dark matter particles, as dumped by GADGET. The positions are given in supergalactic coordinates (SG): [SGX,SGY,SGZ], and are centered on the Milky-Way. They extend in radius to some 8000 km/s. As emphasized, we provide only here a randomly sampled subset of the whole distribution.

Halo Catalogues: they contain the physical properties of all the DM haloes. Our groupfinder algorithm (with a linking length of 0.2 times the mean interparticle separation) has also produced a "linked list" of particles (which is used to retrieve all the particles belonging to a halo). However, the linked list is useless without the full particle distribution, and therefore we do not release it. Recall that the haloes we consider contain at least 10 particles. Among the physical properties are the position and velocity of the center of mass, the position of the most bound particle, the total and virial mass, virial radius, and circular velocity. Note that the virial radius is defined as the radius within which the mean DM density is 200 times the critical density of the Universe.

Galaxy Catalogues: having constructed a merger tree on the DM skeletton, the semi-analytic (SA) prescription allows us to graft galaxy formation on it. The galaxy catalogues, obtained after running the SA algorithm on the merger trees, are restricted to satellite and central galaxies (we discarded the field galaxies, which are not member of any halo at z=0). One will find in these galaxy catalogues the position and velocity of the DM particle associated with the galaxy, the identity of the galaxy (which is by definition the identity of the particle) and its parent halo (among the haloes given in the halo catalogues), whether it is a satellite or a central galaxy, and most importantly its photometric (total and bulge component luminosities) and baryonic properties (such as stellar mass).

List of the properties in the halo catalogues

Note that the haloes are given ordered : the first halo read corresponds to the halo with identity # 1.

The units are given in the reading routines.

• total number of particles in the halo as found by the groupfinder
• virial radius
• virial mass
• circular velocity
• position of the center of mass
• position of the most bound particle
• velocity of the center of mass
  

List of the properties in the galaxy catalogues

Note that the galaxies are given fully unordered : if for instance the first galaxy read is the central galaxy of the halo with identity # 26, the second galaxy read can be, e.g., a satellite galaxy of the halo with identity # 219. However, there is of course sufficient information in the galaxy catalogues to reconstruct the full population of a given halo.

The units are given in the reading routines.

• identity of the galaxy (i.e. that of the DM particle to which it is associated)
• identity of the halo which hosts the galaxy
• total number of particles in that halo (found by the groupfinder)
• whether the galaxy is a satellite or a central galaxy
• the position of the galaxy (i.e. that of its associated DM particle)
• the peculiar velocity of the galaxy (i.e. that of its associated DM particle)
• the total luminosity at z=0 of the galaxy, in four bands: B, V, I, K
• the luminosity at z=0 of the bulge component of the galaxy, in four bands : B, V, I, K
• the mass of cold gas
• the total stellar mass
• the stellar mass of the bulge component
• the total star formation rate, estimated during the most recent redshift interval, including starburst and quiescent star formation
• the redshift when the galaxy was last a central galaxy
• the virial mass of the halo when the galaxy was last a central galaxy
• the disk velocity of the galaxy

SIMULATION PARAMETERS

We define H₀=100 h km/s/Mpc. The other parameters follow standard notation.

Cosmological parameters

Collisionless simulation parameters

The subscripts "hr" and "lr" refer to the high and low resolution regions, respectively.

N is the number of (DM) particles, M the mass (units Msun/h) of one particle, and l_soft is the physical softening length (units kpc/h).

Semi-analytic parameters

f_bar is the baryon fraction: f_bar=Omega_bar/Omega₀

alpha=star formation efficiency, epsilon=SNe feedback efficiency

f_bulge is the ratio of the satellite galaxy total mass to the central galaxy total mass beyond which a merger is supposed to trigger a starburst and form a bulge component

"Feedback" gives the hypothesis that we made for the fate of the cold gas which has been reheated by the SNe (either ejected from the DM halo and later reincorporated or always retained in the halo)

M_B,lum is the luminosity resolution limit of the simulations (in the B band), defined as the mean B band magnitude of the central galaxy of a 10 particle halo at z=0.

M_B,morpho the morphology resolution limit, defined as the mean B band magnitude of the central galaxy of a 100 particle halo at z=0.

Masses for Milky-Way look-alikes

Milky Way look-alikes are defined as galaxies of type Sb/Sc with a disk circular velocity betwen 200 and 240 km/s.

In the table below, masses are given in units of M_sun, disk star formation rates in units of M_sun/year, and we give our zero-point normalization of the Tully-Fisher realtion.

Reading Routines

Note that the units of the fields are given as comments in the routines.

Type of file	F90	IDL
Full set of routines	ReadAll_F90	ReadAll_IDL
Sampled DM distribution	ReadParts.F	ReadParts.pro
Halo catalogue	ReadHaloCat.F	ReadHaloCat.pro
Galaxy catalogue	ReadGalCat.F	ReadGalCat.pro
Mark III catalogue	ReadMarkIII.F	ReadMarkIII.pro
Mock Mark III catalogue	ReadMockMarkIII.F	ReadMockMarkIII.pro

Sampled Dark Matter Distributions

NB : the sizes given refer to the gzipped files.

Halo Catalogues

NB : the sizes given refer to the gzipped files.

Galaxy Catalogues

We WARN that the use of the galaxy catalogues below, and even around the luminosity resolution limit quoted here requires a lot of caution, and is left to the responsibility of the users !

So as to be complete, we provide here two full catalogues (with and without dust) which are not cut in resolution. Besides, we also give a catalogue cut at the luminosity resolution limit, not including dust correction, e.g. to obtain a Tully-Fisher relation to be compared to that of Giovanelli et al. (1997).

Model	LCDM	TCDM
Full catalogue without dust correction	cat_full.galsLCDM (37 MB)	cat_full.galsTCDM (31 MB)
Full catalogue with dust correction	cat_dust_full.galsLCDM (37 MB)	cat_dust_full.galsTCDM (31 MB)
Catalogue cut at the luminosity resolution without dust correction	cat_cutLum.galsLCDM (11 MB)	cat_cutLum.galsTCDM (12 MB)
Catalogue cut at the luminosity resolution with dust correction	cat_dust_cutLum.galsLCDM (11 MB)	cat_dust_cutLum.galsTCDM (12 MB)
Catalogue cut at the morphology resolution with dust correction	cat_dust_cutMorpho.galsLCDM (1.8 MB)	cat_dust_cutMorpho.galsTCDM (1.7 MB)

NB : the sizes given refer to the gzipped files.

MARK III AND MOCK MARK III CATALOGUES

Mock Mark III catalogues of peculiar velocities have been constructed for both cosmologies. They are available as gzipped .tar files (1.2 MB, including the real data).

The reading routines (together with the descriptions of the fields and the units of the data) are given above.

CATALOGUES FOR TEST VOID POPULATIONS

We give in the following table the series of galaxy and halo populations that we considered for hypothetical void fillers in the LCDM simulation analysed in astro-ph/0201193.

For each property, we have separated 7 samples (see preprint). The samples GL and GC are selected above the luminosity resolution limit of the simulation; the sample GM is above the morphology resolution limit. Note that galaxies have been corrected for internal dust extinction.

The reading routines (together with the descriptions of the fields and the units of the data) are given above. For simplicity, the catalogues of DM haloes selected by their mass are written in the format of the galaxy catalogues. There, only the position, mass of the group giving the number of particles and virial mass are relevant fields.
The disk circular velocity is replaced by the virial circular velocity of the halo. Other fields have been set to default values. Alternatively, one can build the samples described in astro-ph/0201193 directly from the above full dust corrected galaxy catalogue and from the halo catalogue.

Property	1	2	3	4	5	6	7
Halo Mass (HM)	HM1(3.4 MB)	HM2	HM3	HM4	HM5	HM6	HM7
Galaxy Luminosity (GL)	GL1(6.5 MB)	GL2(2.9 MB)	GL3(1.3 MB)	GL4	GL5	GL6	GL7
Galaxy Colour (GC)	GC1	GC2(1.7 MB)	GC3(4.5 MB)	GC4(2.4 MB)	GC5	GC6(2.2 MB)	GC7
Galaxy Morphology (GM)	GM1	GM2	GM3	GM4	GM5	GM6	GM7

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Comments to: H. Mathis hmathis@mpa-garching.mpg.de