As part of a long term observational project, we are investigating the macroturbulent broadening in O and B supergiants (Sgs) and its possible connection with spectroscopic variability phenomena and stellar oscillations. We present the first results of our project, namely firm observational evidence for a strong correlation between the extra

We performed J- and R-band linear polarimetry with the 4.2 m William Herschel Telescope at the Observatorio del Roque de los Muchachos and with the 1.6 m telescope at the Observatório do Pico dos Dias, respectively, to derive the magnetic field geometry of the diffuse molecular cloud surrounding the embedded protostellar system NGC 1333 IRAS 4A. We

We present an approach to improve the radial velocity precision of NIRSPEC data (spectral resolution R = λ/Δλ ≈ 22,000) by using a self-calibration approach. We demonstrate that the accuracy can be significantly improved by deconvolving the spectra and using the telluric lines as a long-term stable wavelength reference. HITRAN data base: http://www

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The European Extremely Large Telescope (E-ELT) is the most ambitious of the ELTs being planned. With a diameter of 42 m and being fully adaptive from the start, the E-ELT will be more than one hundred times more sensitive than the present-day largest optical telescopes. Discovering and characterising planets around other stars will be one of the

The extension of the highly successful Doppler technique into the near-infrared (0.9-2.5 μm) is highly desirable as it would open the possibility for searches for extra-solar planets around young stars, very low-mass stars and brown dwarfs. Here we review the current status of this technique and discuss future prospects with particular emphasis on