We present results of an extensive study of the X-ray spectral properties of sources detected in the RIXOS survey, which is a large, nearly complete sample of objects detected serendipitously in ROSAT PSPC fields down to a flux limit of 3x10^-14ergcm^-2s^-1 (0.5-2keV). We show that for X-ray surveys containing sources with low count rate, such as

The stratification with geometrical height of the velocity and temperature 5 minute oscillation through the solar photosphere is obtained after the inversion of a time series of KI 7699 Å line spectra taken at disk center.

A new low-dispersion objective-prism search for low-redshift (z

DENIS is a project to survey the all-southern sky in three wavelength bands (Gunn-i 0.82 μm; J, 1.25 μm; and K_s, 2.15 μm) with limiting magnitudes 18.5, 16.5 and 14.0, respectively. The observations are performed with the 1m-ESO telescope at La Silla (Chile). The DENIS instrument is made up of a 3-channel camera built of commercially available

DENIS is a project to survey the all-southern sky in three wavelength bands (Gunn-i 0.82 μm; J, 1.25 μm; and K_s, 2.15 μm) with limiting magnitudes 18.5, 16.5 and 14.0, respectively. The observations are performed with the 1m-ESO telescope at La Silla (Chile). The DENIS instrument is made up of a 3-channel camera built of commercially available

We analyse the stellar content of almost 300deg^2 of the sky close to the Galactic plane by directly comparing the predictions of the SKY model (Cohen and Wainscoat et al.) with star counts taken from the Two Micron Galactic plane Survey (TMGS: Garzón et al.). Through these comparisons we can examine discrepancies between counts and model and