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We obtained X-ray spectra of the Seyfert 1 galaxy NGC~3516 in March 1995using ASCA. Simultaneous far-UV observations were obtained with HUT on theAstro-2 shuttle mission. The ASCA spectrum shows a lightly absorbed power lawof energy index 0.78. The low energy absorbing column is significantly lessthan previously seen. Prominent O~vii and O~viii absorption edges are visible,but, consistent with the much lower total absorbing column, no Fe K absorptionedge is detectable. A weak, narrow Fe~K$\alpha$ emission line from coldmaterial is present as well as a broad Fe~K$\alpha$ line. These features aresimilar to those reported in other Seyfert 1 galaxies. A single warm absorbermodel provides only an imperfect description of the low energy absorption. Inaddition to a highly ionized absorber with ionization parameter $U = 1.66$ anda total column density of $1.4 \times 10^{22}~\rm cm^{-2}$, adding a lowerionization absorber with $U = 0.32$ and a total column of $6.9 \times10^{21}~\rm cm^{-2}$ significantly improves the fit. The contribution ofresonant line scattering to our warm absorber models limits the Dopplerparameter to $< 160~\rm km~s^{-1}$ at 90\% confidence. Turbulence at the soundspeed of the photoionized gas provides the best fit. None of the warm absorbermodels fit to the X-ray spectrum can match the observed equivalent widths ofall the UV absorption lines. Accounting for the X-ray and UV absorptionsimultaneously requires an absorbing region with a broad range of ionizationparameters and column densities.Comment: 14 pages, 4 Postscript figures, uses aaspp4.sty To appear in the  August 20, 1996, issue of The Astrophysical Journa

ASCA Observations of the Composite Warm Absorber in NGC 3516