We present simultaneous and continuous observations of H_alpha, H_beta, NaI D_1, D_2 and HeI D_3 lines of the chromospherically active binary HR 1099. We have observed HR 1099 for more than 3 weeks almost continuously and monitored two flares. An increase in H_alpha, CaII H & K, H_beta, HeI D_3 and HeI lambda6678 and a strong filling-in of the NaI

The theoretical understanding of the linear standing or propagating magnetohydrodynamic (MHD) waves in a variety of solar coronal structures is far from complete since analytical solutions to the linearised MHD equations can only be found for very simple magnetic configurations. In this work, a numerical code is used to solve the linear MHD wave

We obtained simultaneously recorded time series of broadband images of a sunspot close to the disk center at the German Vacuum Tower Telescope, Tenerife, in two wavelength bands at 0.56 μm and 1.55 μm. Maps of brightness difference images Tb(1.55 μm) and Tb(0.56 μm) were computed for the best image pairs. Furthermore, a scatter plot of the

We have analyzed six OB supergiants and one giant covering spectral types from O3 to B1 in the Galactic OB association Cyg OB2 by means of an updated version of FASTWIND (Santolaya-Rey et al. cite{sph97}) that includes an approximate treatment of metal line blocking and blanketing. This large coverage in spectral type allows us to derive a new

Between October 1999 and October 2000 an undistinguished high-galactic latitude patch of sky, the Hubble Deep Field South (HDF-S), was observed with the VLT for more than 100 hours under the best seeing conditions. Using the near-infrared (NIR) imaging mode of the Infrared Spectrometer and Array Camera (ISAAC, Moorwood 1997), we obtained ultradeep

At this meeting we presented a spinfoam model in which the fundamental "bubble amplitudes" (the analog of the one-loop corrections in QFT) are finite as the cutoff is removed. The model is a natural variant of the field theoretical formulation of the Barrett-Crane model. As the last, the model is a quantum BF theory plus an implementation of the