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We present data from two ASCA observations (1993 March 17.92$-$18.12 and 1993 May 7.24$-$8.09) of the high inclination (i $\approx$ 80$^{\circ}$), dipping, eclipsing Low-mass X-ray Binary EXO\thinspace0748$-$676. We have examined the intensity selected dipping and quiescent (non-dipping,non-eclipsing, non-bursting) behavior of EXO\thinspace0748$-$676 in these observations.
Over the interval of these observations the persistent luminosity of the source decreased by approximately a factor of 5. ``Low-state'' data indicate that we have observed the source near its historical minimum emission state.
The low state quiescent/dipping data show several unusual and outstanding properties: (1) there is no time wherein the intrinsic persistent spectrum is free of some amount of variable column, (2) the dipping morphology of EXO\thinspace0748$-$676 is remarkable; there exists a previously un-noted broad (FWHM $\Delta\Phi \sim $ 0.15) dipping feature centered near $\Phi =$ 0.45, and (3) a previously unparameterized soft (0.4$-$1 keV) ``excess'' exists in low-state dipping spectra. This soft excess is well fit by either a Raymond-Smith plasma or by a thermal bremsstrahlung spectral model (kT $\approx$ 0.15 keV).
Combined archival and ASCA datasets show that the changing accretion structure in this source may play a significant role in the modulation of the long-term brightness of this source.
