distribution of halo virial circular velocities from MMW and the following list of parameters (fiducial values in brackets):

1.  [[$\sigma_{\rm atm}$]{} — the seeing with which we convolve the galaxy profiles (FWHM=0.5arcsec, the quoted average value from Pettini et al. (2001), and Erb et al. (2003))]{}

2.  [[$c$]{} — the concentration parameter of the NFW halo profile (4)]{}

3.  [[$R_0$]{} — scale–radius for the exponential light profile (0.3arcsec); and the spatial cut [$r_{lim}$]{} (0.4arcsec)]{}

4.  [[$V_{min}$]{} — the spectral cut (25[kms$^{-1}$]{} for the ISAAC 1.00arcsec slit and 50[kms$^{-1}$]{} for the NIRSPEC 0.76arcsec slit)]{}

Later we assess how robust are the conclusions to variations in the chosen values of the above parameters.

Results
=======

Measuring [$\alpha(obs)$]{}
---------------------------

The results of the modelling are summarised in the curve of the expected distribution of $V_r/V_{c7}$ plotted in Figure \[fig:lbg\_cumf\]. Also plotted in the figure, as the stepped line, is the distribution of $V_r/\sigma$ for the seven galaxies with recorded rotation velocities. Recall that $\alpha(obs)$ is the value by which the curve should be stretched to fit the stepped line, and that this should be consistent with $\alpha(req)=2.64$ (Figure \[fig:lbg\_mmwdistribution\]) if the massive–halo model is correct.

In Figure \[fig:lbg\_bayesians\](upper) we plot, as the solid 