Simultaneous fit to eight Swift spectra from XMMSL1 J173738.2-595625 of a power law, of fitted index Γ = 1.90 ± 0.04, absorbed by the Galactic column. The normalisation is fairly constant, only varying significantly for the spectrum from 2008-06-03 (red), where it is lower than the brightest spectrum by a factor of five. This change in flux rate is reflected as a dip in the X-ray light curve (see Fig. B.1v). Additional absorption is not required to fit the spectra