The REM Telescope: A robotic multiwavelength facility to promptly follow up GRB afterglows

The REM (Rapid Eye Mount) Telescope, located in la Silla Observatory Chile, is the first moderate (60 cm) aperture robotic telescope able to cover simultaneously both the visible and near-infrared ( 0.45-2.3μm) wavelength range. The high-throughput Infrared Camera (REMIR) and the optical imaging spectrograph (ROSS), both equipping the REM telescope, are simultaneously fed by a dichroic and they allow to collect high-S/N data in an unprecedented large spectral range on a telescope of this size. The wide band covered, the very fast pointing capability (60 degrees in 5 seconds) and its full robotization make REM the ideal experiment for fast transients observation. The REM observatory is an example of a versatile and agile facility necessary to complement large telescopes in fields in which rapid response and/or target pre-screening are necessary. This paper describes the main characteristics and operation modes of the REM observatory and gives an overview of preliminary results obtained during the Science Verification Phase.