of the science data; and a science data reduction to produce a 3D data cube which has been sky subtracted, flat fielded, cleaned of bad pixels, and telluric corrected.

The first two steps in the reduction process were completed by editing processing scripts supplied by the Gemini Observatory. The science reduction also largely followed a Gemini script. However, several additional steps were required to complete the reduction. In particular, the hydrogen Br$\gamma$ absorption line at 2.1661$\mu$m in the spectrum of the standard star chosen for the telluric calibration of each science object had to be removed, the modified spectrum then being divided by the star’s blackbody spectrum and normalised before being divided into the extracted 1D science object spectrum to correct the latter for telluric absorption features.

The spectra were extracted using an aperture size of 1.5 times the full width at half maximum (FWHM) of each object, as determined from the dispersed images, see Table 1.

Observations in the K band are susceptible to contamination by telluric OH sky lines. For the fainter objects observed here, the flux in the sky lines often varied sufficiently during the exposures that the lines were poorly subtracted in the reduction. To remove 