We present observations of the intrinsic absorption in the Seyfert 1 galaxy NGC 3783 obtained with the Space Telescope Imaging Spectrograph ( STIS ) on the Hubble Space Telescope ( HST ) and the Far Ultraviolet Spectroscopic Explorer ( FUSE ) .
We have combined 18 STIS and 5 FUSE observations to obtain a high signal-to-noise averaged spectrum spanning 905–1730 Å .
The averaged spectrum reveals absorption in O vi , N v , C iv , N iii , C iii and the Lyman lines up to Ly \epsilon in the three blueshifted kinematic components previously detected in the STIS spectrum ( at radial velocities of - 1320 , - 724 , and - 548 km s ^ { -1 } ) .
The highest velocity component exhibits absorption in Si iv .
We also detect metastable C iii in this component , indicating a high density in this absorber .
No lower ionization lines , i.e. , C ii and Si ii , are detected .
A weak , fourth absorption component is tentatively detected in the high ionization lines and Ly \alpha and Ly \beta at a radial velocity of - 1027 km s ^ { -1 } .
The Lyman lines reveal a complex absorption geometry .
The strength of the higher order lines indicates Ly \alpha and Ly \beta are saturated over much of the resolved profiles in the three strongest absorption components and , therefore , their observed profiles are determined by the covering factor .
We separate the individual covering factors of the continuum and emission-line sources as a function of velocity in each kinematic component using the Ly \alpha and Ly \beta lines .
The covering factor of the BLR is found to vary dramatically between the cores of the individual kinematic components , ranging from 0 to 0.84 .
Additionally , we find that the continuum covering factor varies with velocity within the individual kinematic components , decreasing smoothly in the wings of the absorption by at least 60 % .
Comparison of the effective covering factors derived from the H i results with those determined directly from the doublets reveals the covering factor of Si iv is less than half that of H i and N v in the high velocity component .
Additionally , the FWHM of N iii and Si iv are narrower than the higher ionization lines in this component .
These results indicate there is substructure within this absorber .
We also find evidence for structure in the column density profiles of the high ionization lines in this component .
We derive a lower limit on the total column ( N _ { H } \geq 10 ^ { 19 } cm ^ { -2 } ) and ionization parameter ( U \geq 0.005 ) in the low ionization subcomponent of this absorber .
The metastable-to-total C iii column density ratio implies n _ { e } \approx 10 ^ { 9 } cm ^ { -3 } and an upper limit on the distance of the absorber from the ionizing continuum of R \leq 8 \times 10 ^ { 17 } cm .
The decreasing covering factor found in the wings of the absorption and the extreme compactness of the C III ^ { * } absorber are suggestive of a clumpy absorption gas with low volume filling factor .