Recent observations of coronal holes with Hinode show with unprecedented detail the launching of fast and hot jets. Many of these jets are found to coincide with the emergence of new magnetic flux, and it is generally assumed that the jets are initiated by magnetic reconnection between the new emerging flux and the existing open magnetic field

We present simultaneous spectropolarimetric observations of four visible (630 nm) and three infrared (1565 nm) spectral lines from the German Vacuum Tower Telescope, together with speckle-reconstructed filtergrams in the G-band and the Ca II H line core from the Dutch Open Telescope. After alignment of the data sets, we used the G-band intensity to

Aims: We analyse the oscillatory properties of resonantly damped transverse kink oscillations in two-dimensional prominence threads. Methods: The fine structures are modelled as cylindrically symmetric magnetic flux tubes with a dense central part with prominence plasma properties and an evacuated part, both surrounded by coronal plasma. The

We have monitored the photometric, spectroscopic and polarimetric variations of the classical T Tauri star (CTTS) AA Tau over a period of a month. The light curve consists of more than 260 measurements in each of the B and V-bands over a continuous time period of 30 days and more than 180 measurements in the R and I-bands. This provides

In a statistical analysis of Debrecen Photoheliographic Results sunspot area data we find that the logarithmic deviation (logD)' of the area decay rate D from the parabolic mean decay law (derived in the first paper in this series) follows a Gaussian probability distribution. As a consequence, the actual decay rate D and the time-averaged decay

ELMER is an optical instrument for the GTC designed to observe between 3650 and 10000 Armstrong. The observing modes for the instrument at Day One shall be: Imaging, Long Slit Spectroscopy, Mask-multi-object spectroscopy, Slit-less multi-object spectroscopy, Fast Photometry and Fast short-slit spectroscopy. It will be installed at the Nasmyth-B