]{}self-absorption model is shown in Figure \[fig:ESO274-crosscorr\] (right). There is again scatter in $M_*/L_{R}$, although the value has dropped compared to the optically thin model. It is now at $0.76^{+0.57}_{-0.26}$. The shape of the halo is identical to the optically thin model, with an oblate shape of $q=0.7^{+0.1}_{-0.1}$. The other parameters are $\rho_{0,\textrm{halo}} = 0.094^{+0.009}_{-0.019}$M$_\odot$/pc$^3$ and $R_c = 1.42^{+0.09}_{-0.03}$kpc. Compared to the optically thin model, the self-absorption [ <span style="font-variant:small-caps;">HI</span> ]{}model produces a dark matter halo with longer scale length $R_c$ and lower central density $\rho_0$.

If we limit the analysis to $M_*/L_R<0.55$, we find that the halo becomes even more oblate, $q = 0.64_{-0.01}^{+0.01}$ for the optically thin and $q =0.67_{-0.01}^{+0.01}$ for the self-absorption model. The central density of the halo also goes up to $\rho_0 = 0.171_{-0.001}^{+0.002}$M$_\odot$/pc$^3$ for the optically thin model, and $\rho_0 = 0.103_{-0.001}^{+0.001}$M$_\odot$/pc$^3$ for the self-absorbing [ <span style="font-variant:small-caps;">HI</span> ]{}. The scale lengths goes down to $h_0 = 1.07_{-0.01}^{+0.01}$kpc and $h_0 = 1.39_{-0.01}^{+0.01}$kpc respectively. A lower mass in the stellar disc thus results in haloes that are more oblate, have higher central core densities and slightly shorter scale lengths.

![image](Petersetal-Vfig9a.jpg){width="40.00000%"} ![image](Petersetal-Vfig9b.jpg){width="40.00000%"} ![image](Petersetal-Vfig9c.jpg){width="40.00000%"} ![image](Petersetal-Vfig9d.jpg){width="40.00000%"} ![image](Petersetal-Vfig9e.jpg){width="40.00000%"} ![image](Petersetal-Vfig9f.jpg){width="40.00000%"}

![image](Petersetal-Vfig10a.jpg){width="40.00000%"} ![image](Petersetal-Vfig10b.jpg){width="40.00000%"} ![image](Petersetal-Vfig10c.jpg){width="40.00000%"} ![image](Petersetal-Vfig10d.jpg){width="40.00000%"} ![image](Petersetal-Vfig10e.jpg){width="40.00000%"} ![image](Petersetal-Vfig10f.jpg){width="40.00000%"}

![image](Petersetal-Vfig11a.jpg){width="49.00000%"} ![image](Petersetal-Vfig11b.jpg){width="49.00000%"}

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