Flux Cancellation in a Decaying Active Region Flux cancellation is observed in many regions on the Sun as internetwork, network and active regions fields. It clearly plays a crucial role in the constant flux processing observed in the solar surface. During the decay of an active region, we have observed the in-situ dissapearance of 70 % of its flux

EMIR is a multiobject intermediate resolution near infrared (1.0-2.5 μm) spectrograph with image capabilities to be mounted on the 10-m Gran Telescopio Canarias (GTC) as one of the first common user instruments. The GTC, located on the Spanish island of La Palma, is due for first light in early 2003. EMIR is being built by a consortium of Spanish

EMIR is a multiobject intermediate resolution near infrared (1.0-2.5 μm) spectrograph with image capabilities to be mounted on the 10-m Gran Telescopio Canarias (GTC) as one of the first common user instruments. The GTC, located on the Spanish island of La Palma, is due for first light in early 2003. EMIR is being built by a consortium of Spanish

Echo Tomography is a powerful technique which enables us to probe the accretion geometry in active LMXBs by studying reprocessing of X-rays into UV/optical radiation. If reprocessing takes place in the companion star, time delay as a function of the orbital phase can yield accurate dynamical masses. Previous attempts, using broad band photometry

We present our results of the dynamical analysis of the rich, hot and very X-ray luminous galaxy cluster A2219, containing a powerful diffuse radio-halo.Our conclusions support the view of the connection between extended radio emission and merging phenomena in galaxy clusters.

The chemical composition of the Universe has evolved over billions of years. A host of astrophysical processes and observations must be understood in order to explain why celestial objects have the chemical compositions observed. This book contains the lectures delivered at the XIII Canary Islands Winter School of Astrophysics, which was dedicated