Swift/XRT results for AX J1538.3–5541. Left: X-ray count rate light curve of the epoch of 2007 August–September (binned per satellite orbit). Right: comparison of the X-ray spectra at high (average of 0.16   c   s^-1; top, black) and low (average of 0.04   c   s^-1; bottom, red) count rates, using all available Swift/XRT observations of the source. The solid lines indicate the best-fit results to an absorbed powerlaw model. The lower panel indicates the data to model ratio of the fits.