New Members of the Cluster Family in Nearby Lenticular Galaxies

Abstract
Using spectra obtained with the Keck I telescope we have demonstrated conclusively that the faint (237--8 Gyr), moderately metal-rich ([Fe/H]=-0.58+/-0.24) and, having a system rotation curve which is very similar to that of the host galaxy, are associated with the lenticular disk. Alpha-element to iron abundance ratios are highly supersolar with [alpha/Fe] between +0.3 and +0.6. With moderately high metallicities and luminosities, and effective radii in the range 7--15 pc (compared to the 2--3 pc sizes typical of normal globular and open clusters), this population of clusters has no known analog in the Milky Way or elsewhere in the Local Group.Comment: 24 pages, 10 figures, 4 tables. Accepted for publication in the Astronomical Journal. Changes: more extensive justification of uniqueness and two additional figure

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