1999ApJ...527..341S

We present results from a campaign of simultaneous X-ray and optical observations of X1254-690 conducted using the Rossi X-Ray Timing Explorer and the CTIO 1.5 m telescope. We find that the usually observed deep X-ray dipping is not seen during the times of our observations, with an upper limit of ∼2% on any X-ray orbital variation, and that the mean optical variability has declined in amplitude from ΔV=0.40±0.02 mag to 0.28±0.01 mag. These findings indicate that the vertical structure on the disk edge associated with the impact point of the accretion stream has decreased in angular size from 17°-25° to less than 10°, and support the suggestions of previous modeling work that the bulge provides 35%-40% of the contribution to the overall optical modulation. The average optical and X-ray brightnesses are comparable to their values during dipping episodes, indicating that the mean M{dot} and disk radius remain unchanged.