KINEMATICS AND METALLICITIES OF GLOBULAR-CLUSTERS IN M104

We have obtained spectra for globular cluster candidates in M104 with the Low Dispersion Survey Spectrograph (LDSS-2) on the William Hersche l Telescope, confirming 34 objects as M104 globular clusters. We find a cluster velocity dispersion of similar to 260 km s(-1), and the proj ected mass estimator gives a mass of 5.0 (3.5, 6.7) x 10(11) M. for M1 04 within a projected radius of similar to 330 arcsec (14 kpc for D = 8.55 Mpc). Our best estimate for the mass-to-light ratio is M/L(vT) = 16(-5.0)(+5.5) within the same radius. Considering all of the possible sources of uncertainty, we find a lower limit of M/L(v) = 5.3, which is larger than the M/L(v) ratio found from rotation curve analyses ins ide 180 arcsec. We thus conclude that the mass-to-light ratio increase s with radius, or in other words that M104 possesses a dark matter hal o. There is a marginal detection of rotation in the M104 cluster syste m at the 92.5 per cent confidence level; larger samples will be needed to investigate this possibility, Interestingly, the M104 globular clu ster and planetary nebulae (PNe) kinematics are roughly consistent ins ide similar to 100 arcsec. Finally, we find a mean cluster metallicity of [Fe/H] = - 0.70 +/- 0.3, which is more typical of clusters in gian t elliptical (gE)/cD galaxies than it is of clusters in other spirals.