The X-ray warm absorber in NGC 3516

The Seyfert 1 galaxy, NGC 3516 has been the subject of many absorption line studies at both ultraviolet and X-ray wavelengths. In the UV, strong, broad, variable associated metal line absorption with velocity width similar to 2000 km s(-1) is thought to originate in gas with N-H greater than or similar to 10(19) cm(-2) lying between 0.01 and 9 pc from the central active nucleus. The Ginga X-ray data are consistent with several possibilities: a warm absorber and a cold absorber combined either with partial covering or an unusually strong reflection spectrum. We present ROSAT observations of NGC 3516 which show a strong detection of a warm absorber dominated by a blend of O VII/O VII edges at similar to 0.8keV with N-H similar to 7x10(21) cm(-2) and U:8-12. We argue that NGC 3516 contains an out flowing ''XUV'' absorber showing the presence of X-ray absorption edges which are consistent with the presence of broad absorption lines in the old IUE spectra and their disappearance in the new UV observations. Our dynamical model suggests that the O VII absorption edge will continue to weaken compared Co the O VII edge, an easily testable prediction with future missions like AXAF. Eventually the source would be transparent to the X-rays unless a new absorption system is produced.