One of the tasks carried out by the Astroparticle Physics Group of the IAC is the analysis of objects observed by the MAGIC telescope looking for very high energy gamma-ray emission. The main goal of these observations is to search for acceleration of cosmic rays sites and the identification of accelerated species. We have analyzed MAGIC data of

We have undertaken a study of the nature of red galaxies at low and intermediate redshifts in the GOYA photometric survey. A new photometric index based on apparent magnitudes has been obtained to separate red galaxies dominated by old populations from those dominated by star formation. A two-component mass code has been used to estimate the

I review some recent advances in methods to diagnose polarized radiation with which we may hope to explore the magnetism of the solar chromosphere and corona. These methods are based on the remarkable signatures that the radiatively induced quantum coherences produce in the emergent spectral line polarization and on the joint action of the Hanle

We have explored radial color and stellar surface mass density profiles for a sample of 85 late-type galaxies with available deep (down to˜27.0mag/arcsec2) SDSS g'- and r'-band surface brightness profiles. About 90% of the light profiles have been classified as broken exponentials, exhibiting either truncations (Type II galaxies) or antitruncations

The γp → η‧p reaction was studied near the threshold, in the 1.44 GeV> Eγ < 1.55GeV energy range with the tagged photons of the former GRAAL experiment. The two neutral decays γγ(Γi/Γ = 2.10 ± 0.12%) and π0π0η(Γi/Γ = 20.7 ± 1.2%) were analized and preliminary results of the beam asymmetry were extracted together with the invariant masses.

The preliminary results obtained by the GRAAL collaboration for the π0π+ photoproduction on the free and quasi-free proton (deuteron) at Eγ = 0.7-1.5 GeV are presented. The total cross section of the γp → π0π+n reaction and invariant mass spectra for the π+π0, π+n and π0n systems are presented in the photon energy range from 0.7 to 1.5 GeV. These