Makrofol detectors are commonly used for long-term radon (Rn-222) measurements in houses, schools and workplaces. The use of this type of passive detectors for the determination of radon concentrations requires the counting of the nuclear tracks produced by alpha particles on the detecting material. The "image reduction and analysis facility" (IRAF

Commission 12 covers research on the internal structure and dynamics of the Sun, the "quiet" solar atmosphere, solar radiation and its variability, and the nature of relatively stable magnetic structures like sunspots, faculae and the magnetic network. There is considerable productive overlap with the other Commissions of Division II as

Table 2 contains the Atomic parameters and measured solar equivalent widths for FeII and Fe I lines. (1 data file).

We explore the angular distribution of two samples of satellite galaxies orbiting isolated hosts extracted from the Sloan Digital Sky Survey Data Release 4. We find a clear alignment of the satellites along the major axis of their hosts when restricting the analysis to red-coloured hosts. The anisotropy is most pronounced for red satellites of red

We present the results of an observational study of the pulsational behavior of the line-profile variable binary components of κ Sco, λ Sco and ɛ Lup. Our research is situated in the framework of a systematic long-term project targeting line-profile variable B-stars in close binaries, with the aim to search for tidally enhanced oscillations.

The reddened open cluster NGC7419 is believed to have a very high fraction of Be stars and present an exceptionally high number of red supergiants (five for no blue supergiants). We present the first results of our recent spectroscopic observations of the cluster, which confirm the high fraction of Be stars. We also find spectral types in good