The MHD normal modes of oscillation of coronal magnetic structures are studied by including two aspects that have not been considered in previous theoretical works of this kind, namely the effects of the magnetic field shear and of the longitudinal propagation in the oscillatory properties of solar coronal structures. We show that, in a cold plasma

We present a photometric survey of bright southern stars carried out using the DENIS instrument equipped with attenuating filters. The observations were carried out not using the survey mode of DENIS, but with individual target pointings. This project was stimulated by the need to obtain near-infrared photometry of stars to be used in early

Rapid developments in near-infrared (NIR) arrays and adaptive optics systems have driven the development of wide-field and high-spatial-resolution, high-optical-quality NIR imagers and spectrographs, providing an unparalleled boost to NIR observations. Based around a 1024 × 1024 pixel2 Hawaii-1 array, the Isaac Newton Group Red Imaging Device

Late-type spiral galaxies are thought to be the dynamically simplest type of disk galaxy and our understanding of their properties plays a key role in galaxy formation and evolution scenarios. The low surface brightness (LSB) galaxy UGC 7321, a nearby, isolated, ``superthin'' edge-on galaxy, is an ideal object to study these purely disk-dominated

We investigate, via numerical simulations, the tidal stripping and accretion of globular clusters (GCs). In particular, we focus on creating models that simulate the situation for the GC systems of NGC 1404 and 1399 in the Fornax cluster, which have poor (specific frequency SN~ 2) and rich (SN~ 10) GC systems, respectively. We initially assign NGC

Clusters of galaxies produce negative features at wavelengths λ > 1.25 mm in cosmic microwave background (CMB) maps by means of the thermal Sunyaev-Zel'dovich (SZ) effect, while point radio sources produce positive peaks. This fact implies that a distribution of unresolved SZ clusters could be detected using the negative asymmetry introduced in the