We study the spatial structure of the 3-dimensional large-scale pattern of the Galactic Magnetic Field using the polarization maps obtained by the WMAP satellite at 22 GHz. By using five different models of the large-scale magnetic field of the Milky Way and a model for the cosmic rays distribution, we predict the expected polarized synchrotron

Context: The effective temperature scale of FGK stars, especially at the lowest metallicities remains a major problem in the chemical abundance analysis of metal-poor stars. Aims: We present a new implementation of the infrared flux method (IRFM) using the 2MASS catalogue. Methods: We computed the theoretical quantities in the 2MASS JHKs filters by

One of the first post-focus instruments of the new solar telescope GREGOR will be a Fabry-Perot spectrometer, which is an upgrade of the Göttingen Fabry-Perot interferometer at the Vacuum Tower Telescope (VTT) on Tenerife. This spectrometer is equipped with a full-Stokes polarimeter. The modulation is performed with two ferroelectric liquid

We request 9.1hrs to obtain IRAC photometry of 11 cold brown dwarfs. The observations will complete the dataset of near-infrared spectroscopy and 1-5um photometry, for known brown dwarfs with spectral types >T7, and temperatures of 500K to 800K. These rare very late- type T dwarfs are the coolest objects known outside of the solar system. For these

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Aims: We present the results from a comprehensive spectroscopic survey of the WINGS (WIde-field Nearby Galaxy-cluster Survey) clusters, a program called WINGS-SPE. The WINGS-SPE sample consists of 48 clusters, 22 of which are in the southern sky and 26 in the north. The main goals of this spectroscopic survey are: (1) to study the dynamics and