We have obtained spectra for globular cluster candidates in M104 with LDSS-2 on the William Herschel Telescope, confirming 34 objects as M104 globular clusters. We find a cluster velocity dispersion of ∼ 260 km/sec, and the Projected Mass Estimator gives a mass of 5.0 (3.5,6.7) × 10 11 M ⊙ for M104 within a projected radius of ∼ 330 ′′ (14 kpc for D=8.55 Mpc). Our best estimate for the mass-to-light ratio is M/L VT = 16 +5.5 −5.0 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 found from rotation curve analyses inside 180 ′′ . We thus conclude that the mass-to-light ratio increases with radius, or in other words that M104 possesses a dark matter halo. There is a marginal detection of rotation in the M104 cluster system at the 92.5% confidence level; larger samples will be needed to investigate this possibility. Interestingly, the M104 globular cluster and planetary nebulae (PNe) kinematics are roughly consistent inside ∼ 100 ′′ . Finally, we find a mean cluster metallicity of [Fe/H] = −0.70 ± 0.3, which is more typical of clusters in gE/cD galaxies than it is of clusters in other spirals.

We present bright galaxy number counts measured with linear detectors in the B, V , I, and K bands in two fields covering nearly 10 square degrees. All of our measurements are consistent with passive evolution models, and do not confirm the steep slope measured in other surveys at bright magnitudes. Throughout the range 16 < B < 19, our B−band counts are consistent with the "high normalization" models proposed to reduce the faint blue galaxy problem. Our K−band counts agree with previous measurements, and have reached a fair sample of the universe in the magnitude range where evolution and K-corrections are well understood.

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We describe MIFS, a second generation integral-field spectrograph for the VLT, operating in the visible wavelength range. It combines a 1 ′ × 1 ′ field of view with the improved spatial resolution provided by multi-conjugate adaptive optics and covers a large simultaneous spectral range (0.6-1.0 µm). A separate mode exploits the highest spatial resolution provided by adaptive optics. With this unique combination of capabilities, MIFS has a wide domain of application and a large discovery potential. The MIFS low-spatial resolution mode (sampled at 0. ′′ 2) combined with the initial MCAO capabilities planned for the VLT will provide ultra-deep fields with a limiting magnitude for spectroscopy of R ∼ 28. MIFS will improve the present day detection limit of Lyα emitters by a factor of 100, and will detect low-mass star-forming galaxies to z ∼ 7. The MIFS high-spatial resolution mode (3 ′′ × 3 ′′ field sampled at 0. ′′ 01) is optimized for the next step in (MC)AO. It will probe, e.g., the relationship between supermassive central black holes and their host galaxy and the physics of winds from accretion disks in young stellar objects at unprecedented spatial resolution. MIFS will extend Europe's lead in integral-field spectroscopy. It capitalizes on new developments in adaptive optics, and is a key step towards instrumentation for OWL.