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C. H. Nelson (UNLV), M. Whittle (U. Va.)
We use measurements of the strengths of the Ca~II triplet and Mg b stellar absorption lines in the nuclear and off-nuclear spectra of Seyfert galaxies to study the origin of the UV/optical continuum. For most of the Seyfert 2 galaies in our sample, dilution by a power-law continuum cannot simultaneously explain objects with strong Ca~II triplet and relatively weak Mg b. Evolutionary synthesis models, however, can explain the line strengths of virtually all Sy 2s. Thus the bulk of the nuclear far-red emission is produced by late-type supergiants, which have strong lines, produced in a burst of star formation as found by Terlevich, Diaz & Terlevich (1990). Off-nuclear line strengths suggest that the continuum source is extended, typically a few hundred parsecs across. Also, objects with the strongest evidence for a burst of star formation occupy the region of the IRAS color-color diagram characteristic of starburst galaxies. These results agree with the conclusions of other studies (e.g. Cid Fernandes & Terlevich, 1995; Heckman et~al. 1995) that the UV/optical continuum in Seyfert 2 galaxies is produced by a circumnuclear starburst.