Search for planets around stars with wide brown dwarfs
Aims: This work aims to better understand the role of wide brown dwarf companions in planetary systems. Methods: We obtained high-resolution spectra of six...
Search for radial velocity variations in eight M-dwarfs with NIRSPEC/Keck II
Context. Radial velocity (RV) measurements from near-infrared spectra have become a potentially powerful tool to search for planets around cool stars and sub...
Search for rings and satellites around the exoplanet CoRoT-9b using Spitzer photometry
Using Spitzer photometry at 4.5 microns, we search for rings and satellites around the long period transiting planet CoRoT-9b. We observed two transits in 2010...
Search for surface magnetic fields in Mira stars. First detection in χ Cygni
Context. So far, surface magnetic fields have never been detected on Mira stars. Only recently have the spectropolarimetric capabilities of measuring it via the...
Search for the sub-stellar lithium depletion boundary in the open star cluster Coma Berenices
Aims: We mainly aim to search for the lithium depletion boundary (LDB) among the sub-stellar population of the open star cluster Coma Berenices. Methods: Since...
Search for torsional oscillations in isolated sunspots
In this work we seek evidence for global torsional oscillations in alpha sunspots. We have used long time series of continuum intensity and magnetic field...
Search for VHE gamma-ray emission from Geminga pulsar and nebula with the MAGIC telescopes
The Geminga pulsar, one of the brighest gamma-ray sources, is a promising candidate for emission of very-high-energy (VHE > 100 GeV) pulsed gamma rays. Also...
Searching for chemical inhomogeneities in open clusters. Analysis of the CN and CH molecular band strengths in NGC 2158, NGC 2420, NGC 2682, NGC 7789, and Berkeley 29
Context. The total mass of a cluster, which is the main parameter determining its ability to host more than one stellar generation, may constitute a threshold...
Searching for filaments and large-scale structure around DAFT/FADA clusters
Context. Clusters of galaxies are located at the intersection of cosmic filaments and are still accreting galaxies and groups along these preferential...