§5.

Observations and Reduction
==========================

We obtained optical spectra of XTE J1118+480 from April 7, 2000 to July 4, 2000 with the ARC 3.5 m telescope at Apache Point Observatory. [ We mostly used the Double Imaging Spectrograph (DIS),]{} but spectra with the Echelle spectrograph were also obtained on April 7, 2000. Table \[tab:obs\] summarizes the dates and other characteristics of our observational campaign.

Most of our observations with DIS were carried out with the high resolution gratings [ (hereafter [*hires*]{})]{} with a 1.5” slit (dispersion 1.6Å pixel$^{-1}$ in the blue, 1.1Å pixel$^{-1}$ in the red, and a resolution of 2 pixels), but we also obtained spectra with the low-resolution gratings (same slit size, dispersion 6.2Å pixel$^{-1}$ in the blue, 7Å pixel$^{-1}$ in the red, and a resolution of 2 pixels;[ hereafter [*lowres*]{})]{} on April 7, 2000. For the DIS high resolution observations, the blue and red gratings were centered on slightly different wavelengths during our various nights of observations, but we generally centered the blue side to cover the H$\beta$ and He[ii]{} $\lambda 4686$ lines, and the red side to cover the H$\alpha$ line. The complete list of spectral coverage for our observations can be found in Table \[tab:obs\]. 