Astrophysics is a very recent development in Spain, but its spectacular evolution in itself constitutes a singular phenomenon that has aroused the interest of sociologists and historians of science alike....

The magnetic field observed in the photosphere and at higher levels of the solar atmosphere is generated in the convective envelope that extends along the first 200 000 km below the solar surface (see DYNAMOS: SOLAR AND STELLAR and SOLAR INTERIOR). To properly understand the solar magnetic cycle, it is necessary to explain the processes whereby the

In the diffusion-collision model, the unfolding or backward rates are given by the likelihood of secondary structural cluster dissociation. In this work, we introduce a backward rate calculation modeled from a Kramers-type thermal tunneling through a barrier, which represents the free energy potential well for buried hydrophobic residues. Our

We detect some objects that can be classified as planetary nebulae candidate s (PNc), using images of a southern region of M 33. This search is the deepest one made up to now in M 33. The search was made with narrow band filters centered on [O III], Hα and adjacent continua. We detect 48 PNc, from which 16 have a ratio of [O III]-to-Hα fluxes

We present Johnson B surface photometry for the UCM Survey galaxies. One-dimensional bulge-disk decomposition is attempted, discussing on fitting functions and computational procedures. The results from this decomposition, jointly with concentration indices and an asymmetry coefficient, are employed to study the morphological properties of these

We have carried out an optical follow-up of twelve ROSAT discovered candidate members of the Coma Berenices open cluster. VRI photometry and low resolution ( ~ 3 Å) spectroscopy in the range 3800-7000 Åwere performed to obtain colour-magnitude diagrams, proper motions, spectral types, chromospheric activity levels and radial velocities that allow