Data obtained at the Observatorio del Teide (Tenerife) during the years 1978 to 1988 using a resonant scattering spectrophotometer, is analyzed to look for variations of the low degree p-mode frequencies along the solar cycle. The analysis based on the cross-correlation of power spectra suggests that the variation of its maximum correlation

Aims: The present study reports measurements of the rotation period of a young solar analogue, estimates of its surface coverage by photospheric starspots and of its chromospheric activity level, and derivations of its evolutionary status. Detailed observations of many young solar-type stars, such as the one reported in the present paper, provide

For a number of reasons, the properties of integrated stellar populations are distributed. Traditional synthesis models usually return the mean value of such distribution, and a perfect fitting to observational data is sought for to infer the age and metallicity of observed stellar populations. We show here that, while this is correct on average

Although it is clear that the circumnuclear regions of galaxies are intimately related to their host galaxies, most directly through their bars, it remains unclear what exactly initiates and fuels nuclear stellar (starburst) and non-stellar (AGN) activity. Deviations from axisymmetry in the gravitational potential of a galaxy, set up by a bar or an

The FT-IR spectra of C76, C78 and C84 fullerenes were recorded in the temperature range comprised between -180°C and +250°C. The purpose of the work is to provide reference infrared spectra for searching higher fullerene homologues in space after the recent and successful discovery of C60 and C70 in a series of different astrophysical objects.

The International Research on the Interior of the Sun (IRIS) helioseismometer measures the full disk line of sight velocity of the Sun. In fact, it makes a photometric mesurement using two monochromatic spectral windows located on the wings of the D1 solar line. This is a non-linear measurement. Before a scientific exploitation of the IRIS data