The catalogues are available as gzipped files. Once gunzip'ed they are simple ASCII tables consisting of a header followed by 6 columns of data. Column 1: id - An integer identifying the particle in the orginal Hubble Volume simulation. This is of little use unless you have access to the 1 Billion particle Hubble Volume simulation data. Note that galaxies with the same ID number (or one that just differs by a sign) are the same particle in the orginal N-body simulation and so have identical positions etc. This occurs as a consequence of how we model biasing and the selection function. Together these factors give us a probability, P, that each simulation particle is to be included as a galaxy in the mock catalogue. We then draw a random integer, I, from a Poisson distribution with mean P and include I copies of the particle in the mock catalogue. Typically, P<<1 and I=0 or 1, but close to the observer and in highly biased regions P can approach or exceed 1 and so I>1 can occur resulting in the multiple copies. For most analysis this causes no problems at all. However in certain applications it maybe necessary to either: i) Randomly perturb the positions of multiple copies do that they are not exactly coincident. Perturbing by around 10s of kpc is perfectly valid as this is below the resolution of the simulation. ii) Keep only one of the N copies but give it weight N . Also note that by applying a low redshift but most of these duplcated particles can be excluded. Column 2: ra - Right Ascension in radians in the interval 0 to 2Pi. (For PSCz we instead list galactic longitude, l .) Column 3: dec - Declination in radians. (For PSCz we instead list galactic latitude, b .) Column 4: mag - Apparent magnitude (B_J for APM/2dF, K for 6dF) (For PSCz we instead list 60 micron flux in mJy.) Column 5: zz - Redshift in the CMB frame. Column 6: zhub - Hubble Flow redshift in the CMB frame. Ie with the effect of the galaxy's peculiar velocity removed. Note that you can convert from the CMB to LG frame by subtracting the velocity of the observer from each galaxy. The observers velocity is in the direction of the real CMB dipole ie l=276 deg b=30 deg and its magnitude is given by vobs=sqrt(vxobs**2+vyobs**2+vzobs**2), where vxobs etc are listed in the catalogue header. Note that vobs = 625 +/- 25 km/s as this is one of the constraints applied when choosing the observer. Example: # ng= 198642 # xobs= 1360.500 yobs= 1307.400 zobs= 739.100 Mpc/h # vxobs= -345.000 vyobs= 306.000 vzobs= -394.000 km/s # mockseed= -359078 # omega0= 1.000 # lambda0= 0.000 # sigma_8= 0.600 # basis: 0.24802 -0.21798 0.94391 # -0.90198 -0.40743 0.14291 # 0.35343 -0.88684 -0.29767 # # id ra dec mag zz zhub 672624919 3.7005867986427 -0.4782340482322 11.467 0.03182 0.02946 672624913 3.6476975167684 -0.5123586137846 12.467 0.03202 0.02899 672624914 3.6531152419017 -0.5007377672143 11.420 0.03055 0.02822 672624892 3.5813182714546 -0.5173702293422 13.340 0.03078 0.02853