AN X-RAY DIP IN THE X-RAY TRANSIENT 4U-1630-47

An X-ray dip was observed during a 1996 Rossi X-Ray Timing Explorer ob servation of the recurrent X-ray transient 4U 1630-47. During the dip, the 2-60 keV X-ray flux drops by a factor of about 3, and, at the low est point of the dip, the X-ray spectrum is considerably softer than a t nondip times. We find that the 4U 1630-47 dip is best explained by a bsorption of the inner part of an accretion disk, while the outer part of the disk is unaffected. The spectral evolution during the dip is a dequately described by the variation of a single parameter, the column density obscuring the inner disk.