Hubble Volume Mock Catalogues

Selection Functions and Biasing

APM and 2dF

In the B_J band we model the z=0 luminosity function by a Schechter function with the parameters:

For Omega=0.3 Lambda=0.7: In the LCDM03 mocks we used

  • phi_star = 0.016368 (Mpc/h)^-3
  • BJ_star = -19.673
  • alpha = 1.208

    We assume a mean k+e correction of the form K+E = (z+6.0*z**2)/(1.0+20.0*z**3)

    The adopted biasing parameters were alpha=0.45 and beta=-0.18

    These parameters are as described the MNRAS paper Norberg etal (2002) "The 2dFGS: Galaxy Luminosity Function and Survey Selection Function"

    While in LCDM04 and LCDM04r we made very small tweaks to be consistent with the final 2dFGRS calibration and instead adopted

  • phi_star = 0.015 (Mpc/h)^-3
  • BJ_star = -19.725
  • alpha = 1.18

    We assume a mean k+e correction of the form K+E = (z+6.0*z**2)/(1.0+8.9*z**2.5)

    The adopted biasing parameters were alpha=0.45 and beta=-0.14

    Estimates of the resulting galaxy (ansd masss) power spectra obtained from the full Hubble Volume cube can be found in the following files

  • power.lcdm04.rspace.dat Real-space spherically averaged galaxy P(k)
  • power.lcdm04.zspace.dat Redshift-space spherically averaged galaxy P(k)
  • power.lcdm_mass.rspace.dat Real-space spherically averaged mass P(k)

    These parameters are as described the MNRAS paper Cole etal (2005) "The 2dFGS: Power-spectrum analysis of the final dataset and cosmological implications"

    The magnitude limit of all the catalogues is uniform and considerably deeper than that of the 2dFGRS redshift survey essentially as deep as the photometric APM survey. Thus to make mocks of the redshift catalogues one should view these catalogues through the 2dF magnitude limit and redshift completeness masks or ask Shaun.Cole@durham.ac.uk for catalogues that have been processed this way.

    Older APM and 2dF

    In the B_J band we model the z=0 luminosity function by a Schechter function with the parameters:

    For Omega=1.0:

  • phi_star = 0.016726 (Mpc/h)^-3
  • BJ_star = -19.69
  • alpha = 1.179

    For Omega=0.3 Lambda=0.7:

  • phi_star = 0.014131 (Mpc/h)^-3
  • BJ_star = -19.805
  • alpha = 1.179

    We assume a mean k+e correction of the form K+E = 0.03*z/(0.01+z^4)

    These models both produce 164.5 gals per square degree brighter than the 2dF limit of B_J=19.45. This is in good agreement with the most recently calibrated APM catalogue after dust extinction corrections based on the published SFD dust maps.

    The magnitude limit we have taken for the APM and 2dF catalogues is B_J=20.5. IE this is deeper than the 2dF redshift survey and essentially as deep as the photometric APM survey.

    6dF

    In the K band we model the z=0 luminosity function by a Schechter function with the parameters:
  • phi_star = 0.0108 (Mpc/h)^-3
  • BJ_star = -23.44
  • alpha = 0.96

    We assume a mean k+e correction of the form K+E = -2.5*z .

    The magnitude limit we have taken for the 6dF catalogues is B_J=13.5 . IE this is deeper than the planned redshift survey.

    PSCz

    In this case we have adopted a simple selection function that ignores both relativistic corrections and k+e corrections. as given by the PSCz consortium at
    ftp://ftp-astro.physics.ox.ac.uk/pub/users/wjs/pscz/psi.f

    It is defined by:

    
    c Model of PSCZ selection function  r in Mpc/h taken from
    c ftp://ftp-astro.physics.ox.ac.uk/pub/users/wjs/pscz/psi.f
    c but boosted in number density by 25% to match actual number 
    c in PSCz redshift catalogue
    c
    c  r -- distance in units of Mpc/h
    c
          real function sel(r)
    c************************************************************************
          implicit none
          real r,psistar,alpha,alrstar,beta,gamma,eps,alr,del,fudge
          data psistar,alpha,alrstar,beta,gamma/
         &  0.0077115800,1.81726,1.93673,4.42847,1.56137/
           data eps/1e-5/
           data fudge/1.25188/
    c************************************************************************ 
           alr=alog10(max(r,eps))
            del = alr-alrstar
             sel = fudge*psistar * 10**((1-alpha)*del) / 
         &   (1 + (10**(gamma*del)))**(beta/gamma)
          return
          end
    

    In the catalogue file fluxes in mJ replace the magnitudes used in the other catalogues.