SPECTROSCOPY OF DWARF ELLIPTIC GALAXIES IN THE FORNAX CLUSTER

We present the results of spectroscopic observations of 10 nucleated d warf elliptical galaxies (dE's) in the Fornax cluster. The blue spectr a of Fornax dE galaxies indicate a wide range of metallicities at a gi ven luminosity, similar to those of intermediate to metal-rich globula r clusters. Metal abundances derived in this paper are well correlated with optical colors and agree with previous spectroscopic results. A discrepancy with metallicities inferred from infrared colors is eviden t; possible causes include an intermediate age population and dilution of spectral features by a blue light excess. Dwarf ellipticals exhibi t a wide variation of hydrogen line strength which points to a complex star formation history. Prominent Balmer absorption lines are the sig nature of a young stellar population in the nuclei of some (but not al l) dE's, while moderately strong Balmer lines in relatively metal-rich dE's are more consistent with an extended main sequence. In a few met al-poor dE galaxies, the hydrogen lines are consistent with, or perhap s weaker than, those found in Galactic globulars of similar metallicit y. In the limited magnitude range of this sample, there is no apparent correlation of metallicity either with effective and central surface brightness, or with total and nuclear magnitudes. The velocity distrib ution of the Fornax dwarfs is flatter than that of brighter galaxies a t the 75% confidence level, possibly indicating a difference in the ki nematics of the two samples.