write(10) ndummy,n
write(10) zmax_cat
write(10) ismc
write(10) xc,yc,zc,basis(3,3),mockseed,vxc,vyc,vzc
write(10) sigma_8,omega_0,lambda_0
write(10) (x(i),i=1,n)
write(10) (y(i),i=1,n)
write(10) (z(i),i=1,n)
write(10) (zh(i),i=1,n)
write(10) (mag(i),i=1,n)
write(10) (zhmax(i),i=1,n)
write(10) (id(i),i=1,n)
ndummy=0,ismc=2 | Both of these values can be ignored. |
n | The number of galaxies in the catalogue. |
zmax_cat | The highest redshift in the galaxy catalogue. |
xc,yc,zc,basis(3,3),mockseed,vxc,vyc,vzc | This record can be skipped. It contains information relating the catalogue to the N-body simulation from which it was constructed |
sigma_8,omega_0,lambda_0 | The cosmological model parameters. |
x(i),y(i) and z(i) | These vectors contain the cartesian x,y,z redshift space
postions of the catalogue galaxies. The units are such that zz(i) = sqrt(x(i)^2+y(i)^2+z(i)^2) is the galaxy redshift. For the 2dF catalogues: RA and Dec are then given by sin(dec)=z/zz tan(ra)=y/x For SDSS the same relations yield as SDSS latitude and longitude sin(lat)=z/zz tan(long)=y/x |
zh(i) | Is the redshift the galaxy would have if it had no peculiar velocity. |
mag(i) | galaxy apparent magnitude B_J |
zhmax(i) | maximum redshift at which the galaxy would enter into the catalogue taking account of k-correction and any luminosity evolution. Thus selecting galaxies with zz(i) < zcut and zhmax(i) > zcut will produce a volume limited catalogue |
id(i) | particle index in orginal simulation (ignore) |
Redshift | Co-moving Distance | Number of Galaxies | Number density |
---|---|---|---|
z | r | N(z) | n(z) |
The final comment line quotes the mean surface density of galaxies per square degree at the magnitude limit of the survey.
r | is the comoving distance to redshift z in Mpc/h |
N(z) | is the expected number of galaxies in the catalogue with redshift less than z. |
n(z) | is the expected galaxy number density per (Mpc/h)^3 at redshift z. |