S3SAX-Sky
OERC logo SKADS logo

Overview

S3-SAX-Sky is a semi-analytic simulation of a sky field with apparent emission-line properties of HI and CO from about 2.8×108 galaxies. This simulation was obtained by transforming the cubic simulation box with evolving galaxies (see S3-SAX-Box) into a virtual observing cone (Obreschkow et al., 2009d), using techniques similar to those described by Blaizot et al., 2005.

The global characteristics of the simulation are:

  • Apparent galaxy properties: position, redshift, line fluxes, line profiles, and disk sizes for HI and various CO lines.
  • Intrinsic galaxy properties: all the 62 properties listed in the DeLucia2006a-catalogue, such as absolute magnitudes, colours, star formation rates, etc.
  • Completeness: The simulation is complete for galaxies with cold hydrogen masses (HI+H2) above 108 solar masses.
  • Field-of-view: depends on the selected maximal redshift zmax, such as shown in the table below.

Field-of-view

The apparent position of each galaxy is represented by two coordinates "ra" and "decl". The sky field is centred around ra = 0 and decl = 0. The user can specify a range for ra and decl, as well as for the redshift (or comoving distance to the observer). The available range of ra and decl (i.e. the field-of-view), is related to the upper redshift limit zmax (or the maximal comoving distance Dc,max), such as show in the figure below.

Mockcone

Explicitly, the transverse diameter of the simulated sky field equals the comoving side length sbox of the cubic simulation box of the S3-SAX-Box simulation, which is identical to the side length of the Millennium simulation. There are two versions of the Millennium simulation, a full simulation with sbox = 500/h Mpc 685 Mpc and a smaller test-version, called the Milli-Millennium simulation, with sbox = 62.5/h Mpc 85.6 Mpc. The corresponding opening angles φ for various values of zmax and Dc,max are shown in the table below. The for a given value of zmax or Dc,max the largest available field-of-view is given by |ra|<φ/2 and |decl|<φ/2.

zmax Dc,max
[Gpc]
Millimillennium
sbox = 62.5/h Mpc
Millennium
sbox = 500/h Mpc
φ [deg] φ/2 [deg] φ [deg] φ/2 [deg]
0.10.403 12.2036.101 116.48658.243
0.20.7896.22 3.1151.448 25.724
0.31.1584.237 2.11834.402 17.201
0.41.513.25 1.62526.225 13.113
0.51.8442.661 1.33121.412 10.706
0.62.162.271 1.13518.243 9.121
0.72.461.994 0.99716.002 8.001
0.82.7451.787 0.89414.336 7.168
0.93.0131.628 0.81413.051 6.526
13.2681.501 0.75112.031 6.015
1.23.7371.313 0.65610.515 5.258
1.44.1591.179 0.599.4464.723
1.54.3551.127 0.5639.021 4.511
1.64.541.08 0.548.6524.326
1.84.8851.004 0.5028.039 4.02
25.1990.943 0.4727.553 3.777
2.55.8740.835 0.4186.685 3.343
36.4250.764 0.3826.111 3.055
3.56.8860.712 0.3565.702 2.851
47.2780.674 0.3375.394 2.697
57.9120.62 0.314.9622.481
109.6590.508 0.2544.064 2.032
1510.5050.467 0.2333.736 1.868
2011.0270.445 0.2223.559 1.78

Data structure and access

We have produced two mock skies, one based on the Millennium simulation (sbox = 500/h Mpc 685 Mpc) and one based on the Millimillennium simulation (sbox = 62.5/h Mpc 85.6 Mpc). For a given redshift zmax, the field-of-view (solid angle) of the second mock sky is 64 times smaller. The latter is therefore ideal for testing purposes, since it allows time-efficient SQL-queries.

Each simulated galaxy is specified by a list of properties, which have been stored in two separate tables. In those tables, each row represents exactly one galaxy. Both tables contain the same galaxies in the same order. The columns of the tables represent the different galaxy properties. The first table is called "galaxies_line" (for the Millennium simulation) or "milli_galaxies_line" (for the Millimillennium simulation). It contains the apparent position and emission line properties of the galaxies. The second table, called "galaxies_delu" or "milli_galaxies_delu" contains the intrinsic properties of the DeLucia2006a-catalog, which has been distributed as part of the Millennium Simulation databases. The two tables can be queried simultaneously; e.g. it is possible to request all the HI-line fluxes (1st table) of all galaxies with a given absolute blue magnitude (2nd table).

The tables "galaxies_line", "milli_galaxies_line", "galaxies_delu", and "milli_galaxies_delu" can be queried on this page.

Structure of the tables "galaxies_line" and "milli_galaxies_line"

ColumnPropertyTypeDescriptionUnit
1idBIGINTUnique galaxy identifier in the mock sky-
2galaxyidBIGINTGalaxy identifier in the "DeLucia2006a" catalog of the Millennium Database-
3boxINTBox index in the mock observing cone-
4raFLOATRight ascensiondeg
5declFLOATDeclinationdeg
6distanceFLOATComoving distance to the objectMpc
7zapparentFLOATApparent redshift (including Dopple correction)-
8hubbletypeFLOATNumerical Hubble type along the RC2 sequence -6,...,10-
9himassFLOATHI-massMsun
10h2massFLOATH2-massMsun
11hiintfluxFLOATVelocity-integrated line flux of HI-lineJy km/s
12cointflux_1FLOATVelocity-integrated line flux of CO(1-0)-lineJy km/s
13cointflux_2FLOATVelocity-integrated line flux of CO(2-1)-lineJy km/s
14cointflux_3FLOATVelocity-integrated line flux of CO(3-2)-lineJy km/s
15cointflux_4FLOATVelocity-integrated line flux of CO(4-3)-lineJy km/s
16cointflux_5FLOATVelocity-integrated line flux of CO(5-4)-lineJy km/s
17cointflux_6FLOATVelocity-integrated line flux of CO(6-5)-lineJy km/s
18cointflux_7FLOATVelocity-integrated line flux of CO(7-6)-lineJy km/s
19cointflux_8FLOATVelocity-integrated line flux of CO(8-7)-lineJy km/s
20cointflux_9FLOATVelocity-integrated line flux of CO(9-8)-lineJy km/s
21cointflux_10FLOATVelocity-integrated line flux of CO(10-9)-lineJy km/s
22diskpositionangleFLOATPosition angle measured from north towards eastrad
23diskinclinationFLOATInclination : 0=face-on, pi/2=edge-onrad
24gasscaleradiusFLOATExponential scale radius of the cold gas disk (HI+H2+He)kpc
25rmolcFLOATH2/HI surface density ratio at the disk center ('Rmolc' in the paper)-
26hiaxisratioFLOATMinor axis/major axis for HI-
27himajoraxis_msunpcFLOATHI-radius where Sigma_HI = 1 Msun/pc^2arcsec
28himajoraxis_maxFLOATHI-radius where Sigma_HI is maximal arcsec
29himajoraxis_50maxFLOATHI-radius where Sigma_HI is at 50% of its maximumarcsec
30himajoraxis_10maxFLOATHI-radius where Sigma_HI is at 10% of its maximumarcsec
31himajoraxis_halfmassFLOATHI-radius containing half of the HI-massarcsec
32h2axisratioFLOATMinor axis/major axis for H2-
33h2majoraxis_msunpcFLOATH2-radius where Sigma_H2 = 1 Msun/pc^2arcsec
34h2majoraxis_50maxFLOATH2-radius where Sigma_H2 is at 50% of its maximumarcsec
35h2majoraxis_10maxFLOATH2-radius where Sigma_H2 is at 10% of its maximumarcsec
36h2majoraxis_halfmassFLOATH2-radius containing half of the H2-massarcsec
37balancemajoraxisFLOATRadius where Sigma_HI = Sigma_H2arcsec
38hilumcenterFLOATNormalized central luminosity density at rest-frame (already corrected for the galaxy inclination according to eq. (11) in Obreschkow et al., 2009d)s/km
39hilumpeakFLOATNormalized peak luminosity density at rest-frame (already corrected for the galaxy inclination according to eq. (12) in Obreschkow et al., 2009d)s/km
40hiwidthpeakFLOATLine width between the two horns of the HI-line profile (already corrected for the galaxy inclination according to eq. (10) in Obreschkow et al., 2009d)km/s
41hiwidth50FLOATLine width at 50% of peak luminosity density (already corrected for the galaxy inclination according to eq. (9) in Obreschkow et al., 2009d)km/s
42hiwidth20FLOATLine width at 20% of peak luminosity density (already corrected for the galaxy inclination according to eq. (8) in Obreschkow et al., 2009d)km/s
43columcenterFLOATNormalized central luminosity density at rest-frame (already corrected for the galaxy inclination according to eq. (11) in Obreschkow et al., 2009d)s/km
44columpeakFLOATNormalized peak luminosity density at rest-frame (already corrected for the galaxy inclination according to eq. (12) in Obreschkow et al., 2009d)s/km
45cowidthpeakFLOATLine width between the two horns of the molecular line profile (already corrected for the galaxy inclination according to eq. (10) in Obreschkow et al., 2009d)km/s
46cowidth50FLOATLine width at 50% of peak luminosity density (already corrected for the galaxy inclination according to eq. (9) in Obreschkow et al., 2009d)km/s
47cowidth20FLOATLine width at 20% of peak luminosity density (already corrected for the galaxy inclination according to eq. (8) in Obreschkow et al., 2009d)km/s
48cofillingfactorFLOAT0..1 Filling factor of CO in velocity+space-

 

Structure of the tables "galaxies_delu" and "milli_galaxies_delu"

(columns identical to the DeLucia2006a catalogue, with the exception of our additional index "id")

ColumnPropertyTypeDescription
1idBIGINTUnique galaxy identifier in the mock sky
2galaxyidBIGINTsee DeLucia2006a
3lastprogenitoridBIGINTsee DeLucia2006a
4descendantidBIGINTsee DeLucia2006a
5haloidBIGINTsee DeLucia2006a
6subhaloidBIGINTsee DeLucia2006a
7fofidBIGINTsee DeLucia2006a
8treeidBIGINTsee DeLucia2006a
9firstprogenitoridBIGINTsee DeLucia2006a
10nextprogenitoridBIGINTsee DeLucia2006a
11typeTINYINTsee DeLucia2006a
12snapnumINTsee DeLucia2006a
13redshiftFLOATsee DeLucia2006a
14centralmvirFLOATsee DeLucia2006a
15phkeyINTsee DeLucia2006a
16xFLOATsee DeLucia2006a
17yFLOATsee DeLucia2006a
18zFLOATsee DeLucia2006a
19zcurveindexINTsee DeLucia2006a
20ixINTsee DeLucia2006a
21iyINTsee DeLucia2006a
22izINTsee DeLucia2006a
23velxFLOATsee DeLucia2006a
24velyFLOATsee DeLucia2006a
25velzFLOATsee DeLucia2006a
26npINTsee DeLucia2006a
27mvirFLOATsee DeLucia2006a
28rvirFLOATsee DeLucia2006a
29vvirFLOATsee DeLucia2006a
30vmaxFLOATsee DeLucia2006a
31coldgasFLOATsee DeLucia2006a
32stellarmassFLOATsee DeLucia2006a
33bulgemassFLOATsee DeLucia2006a
34hotgasFLOATsee DeLucia2006a
35ejectedmassFLOATsee DeLucia2006a
36blackholemassFLOATsee DeLucia2006a
37metalscoldgasFLOATsee DeLucia2006a
38metalsstellarmassFLOATsee DeLucia2006a
39metalsbulgemassFLOATsee DeLucia2006a
40metalshotgasFLOATsee DeLucia2006a
41metalsejectedmassFLOATsee DeLucia2006a
42sfrFLOATsee DeLucia2006a
43sfrbulgeFLOATsee DeLucia2006a
44xraylumFLOATsee DeLucia2006a
45diskradiusFLOATsee DeLucia2006a
46coolingradiusFLOATsee DeLucia2006a
47mag_bFLOATsee DeLucia2006a
48mag_vFLOATsee DeLucia2006a
49mag_rFLOATsee DeLucia2006a
50mag_iFLOATsee DeLucia2006a
51mag_kFLOATsee DeLucia2006a
52mag_bbulgeFLOATsee DeLucia2006a
53mag_vbulgeFLOATsee DeLucia2006a
54mag_rbulgeFLOATsee DeLucia2006a
55mag_ibulgeFLOATsee DeLucia2006a
56mag_kbulgeFLOATsee DeLucia2006a
57mag_bdustFLOATsee DeLucia2006a
58mag_vdustFLOATsee DeLucia2006a
59mag_rdustFLOATsee DeLucia2006a
60mag_idustFLOATsee DeLucia2006a
61mag_kdustFLOATsee DeLucia2006a
62massweightedageFLOATsee DeLucia2006a
63randomINTsee DeLucia2006a