RESOLVING THE INTRINSIC C-IV ABSORPTION IN THE SEYFERT-1 GALAXY NGC-3516

We observed the Seyfert 1 galaxy NGC 3516 with the Goddard High Resolu tion Spectrograph on the Hubble Space Telescope, and obtained UV spect ra at a resolution of lambda/Delta lambda approximate to 20,000 in the redshifted C IV lambda 1549 region. The intrinsic C rv absorption in the core of the broad emission line is resolved for the first time int o four distinct kinematic components, which are all blueshifted, relat ive to the systemic radial velocity of the host galaxy. Two components are narrow (similar to 20 and similar to 30 km s(-1) FWHM) and at sma ll radial velocities (-90 and -30 km s(-1), respectively), and could a rise from the interstellar medium or halo of the host galaxy. The two broad components are centered at radial velocities of -380 and -150 km s(-1), have widths of 130 and 210 km s(-1) FWHM, respectively, and mo st likely arise in out flowing gas near the active nucleus. At the tim es of observation, 1995 April 24 and 1995 October 22, there was no evi dence for the variable absorption component at a higher outflow veloci ty that disappeared some time after 1989 October. The cores of the bro ad C rv absorption components are very close to zero intensity, indica ting that the absorption regions are extended enough to occult complet ely the broad C Iv emitting region (which is similar to 9 light-days i n extent). The total column density of the C rv absorption is substant ially larger than that measured by Kriss et al. from contemporaneous H opkins Ultraviolet Telescope (HUT) spectra, but we agree with their co nclusion that the UV absorption is too strong to arise primarily from the X-ray warm absorber region. The GHRS observations, separated by si x months, reveal no appreciable changes in the equivalent widths or ra dial velocities of any of the absorption components, although a change in the column density of either broad component at a level less than or equal to 25% cannot be ruled out, because the lines are highly satu rated. At present, we know of two Seyfert galaxies, NGC 3516 and NGC 4 151, with complex multiple absorption zones, which can remain stable i n column density and velocity held over timescales of months to years.