disk profile. This component also seems to be present in the high resolution DIS spectra (see Fig. \[fig:sumlines\]). The Bowen blend, which is very weak in the DIS [*hires*]{} spectra, was not detected on April 7 in either the DIS [*lowres*]{} or the Echelle spectra.

Measuring the lines proved difficult, not because of a lack of counts in the spectra but because of their intrinsic broadness and weakness. As a rule, we performed two-component Gaussian fits to the emission lines. For H$\gamma$ and H$\beta$ the two emission components were subtracted to measure the equivalent width (EW) and FWHM of the absorption trough. The EW of the lines varies (with large associated errors) within a night but we could find no periodic behaviour linked to the [ photometric]{} period. We also tried to estimate the semi-amplitude velocity of the primary $K_1$ by fitting the wings of the He[ii]{} line (expected to trace the motion of the compact star) and folding around the suspected $P_{\rm orb}$ of 0.17 day. This did not lead to any result as could be expected from the usually low $K_1$ of SXTs ($K_1\lsim 50$ km s$^{-1}$).

The evolution of these lines during the 3 months of observations 