Astronomical instrumentation

Abstract:

Red spectra of a sample of low-mass stars and brown dwarfs in the Orion Trapezium cluster are discussed. They show late-type spectral characteristics confirming cluster membership and some show evidence of circumstellar activity.

Abstract:

We present very deep JHK imaging of the Trapezium Cluster obtained with Gemini South/Flamingos and Gemini North/Hokupa'a. These images probe the IMF down to similar to 2 M-Jup in a total area of similar to 8 arcmin(2). Several very faint new planetary mass candidates are detected and sources previously detected with UKIRT are verified. Photometry of 124 point sources in this field produces a Luminosity Function which. drops to zero at K=18.75. Allowing. for modest extinction this corresponds to a possible turn-down in the IMF near 5 Mjup. A minority of PMOs exhibit large K band excesses attributed to hot dust, confirming their extreme youth. Some of the faintest sources are associated with short trails of light of uncertain nature. These may provide a clue to the origin of PMOs, perhaps marking evacuated paths cleared by rapidly moving objects.

Abstract:

We present results from a new and unique integral-field spectrograph, SAURON. It has a large field of view and high throughput and is primarily built for the study of stellar & gaseous kinematics and stellar populations in galaxies. Its aim is to carry out a systematic survey of the velocity fields, velocity dispersions, and line-strength distributions of nearby ellipticals, lenticular galaxies and spiral bulges.

Abstract:

SINFONI is an adaptive optics assisted near-infrared integral field spectrometer for the ESO VLT. The Adaptive Optics Module (built by the ESO Adaptive Optics Group) is a 60-elements curvature-sensor based system, designed for operations with natural or sodium laser guide stars. The near-infrared integral field spectrometer SPIFFI (built by the Infrared Group of MPE) provides simultaneous spectroscopy of 32 x 32 spatial pixels, and a spectral resolving power of up to 3300. The adaptive optics module is in the phase of integration; the spectrometer is presently tested in the laboratory. We provide an overview of the project, with particular emphasis on the problems encountered in designing and building an adaptive optics assisted spectrometer.