Context. The tumbling pattern of a bar is the main parameter characterising its dynamics. From numerical simulations, its evolution since bar formation is tightly linked to the dark halo in which the bar is formed through dynamical friction and angular momentum exchange. Observational measurements of the bar pattern speed with redshift can restrict

More than 2000 stars distributed in the field of view of 35 planetary nebulae, and 31 stars from the spectral catalog of Jacoby et al. (1984, Cat. III/92) were observed with the LDSS2 (Low Dispersion Survey Spectrograph) at the William Herschel Telescope (WHT) on La Palma, Spain. (1 data file).

Context. The properties of variable stars can give independent constraints on the star formation history of the host galaxy, by determining the age and metallicity of the parent population. Aims: We investigate the pulsation properties of 84 Anomalous Cepheids (ACs) detected by the OGLE-III survey in the Large Magellanic Cloud (LMC), in order to

The surface deformation has been an essential parameter for the onset and evolution of the eruptive process of the island of El Hierro (October 2011) as well as for forecasting changes in seismic and volcanic activity during the crisis period. From GNSS-GPS observations the reactivation is early detected by analizing the change in the deformation

The uptake of anthropogenic CO2 by the oceans since the industrial revolution is considered to have considerably buffered atmospheric CO2 increases and thereby slow global climate change. However, the CO2 uptake is reducing the ocean's capacity to absorb future atmospheric CO2 which may lead to more pronounced climate forcings. We investigated the

Context. The mechanisms producing the diffuse radio emission in galaxy clusters, and in particular their connection with cluster mergers, are still debated. Aims: We seek to explore the internal dynamics of the cluster Abell 1758N, which has been shown to host a radio halo and two relics, and is known to be a merging bimodal cluster. Methods: Our