Results are presented for three-color photometry and observations with an intensified image dissector-scanner of the central regions of Markarian 359, a face-on galaxy with a compact nucleus that contains dense permitted-line gas in which the apparent velocity dispersion is only a few hundred kilometers/sec. UBV photometric data are reported for six circular regions centered on the galactic nucleus, and the emission-line intensities in the wavelength range from 3400 to 6800 A are examined. It is found that the line intensities are like those which would result if the broad permitted lines were largely removed from the spectrum of a Seyfert nucleus of class 1 and that the H-beta line is broader than the forbidden O III line but not nearly as wide as the broad permitted component in a typical Seyfert 1 spectrum. The differences in line width are explained in terms of a gas component which is too dense to emit much forbidden-line radiation and which has a larger velocity dispersion than the lower-density gas where the forbidden lines originate. Further observations of this unusual galaxy are recommended.
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Davidson et al. (1978) studied this question.