Svensmark et al. (2009) have recently claimed that strong galactic cosmic ray (GCR) decreases during ‘Forbush Decrease (FD) events’ are followed by decreases in both the global liquid water cloud fraction (LCF) and other closely correlated atmospheric parameters. To test the validity of these findings we have concentrated on just one property, the

We study the disc emission component hidden in the single-peaked broad emission lines (BELs) of active galactic nuclei. We compare the observed broad lines from a sample of 90 Seyfert 1 spectra taken from the Sloan Digital Sky Survey with simulated line profiles. We consider a two-component broad line region model where an accretion disc and a

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Collisional excitation of neutral hydrogen atoms can significantly increase the intensity of Balmer lines with respect to pure recombination. If this effect is not taken into account, the abundance analysis of these objects returns biased values, and the bias may be significant if accuracies better than a few percent are required. The most affected

Aims. We aimed at finding a physical explanation for the occurrence of macroturbulence in the atmospheres of hot massive stars, a phenomenon found in observations for more than a decade but that remains unexplained. Methods: We computed time series of line profiles for evolved massive stars broadened by rotation and by hundreds of low-amplitude

We use the OSUBSGS (Ohio State University Bright Spiral Galaxy Survey, Eskridge et al. 2002) and NIRS0S (Near-IR S0 Survey, Laurikainen et al. 2005) data to study the connection of bars and outer spiral structures. Using near-IR images, the non-axisymmetric gravity perturbation associated with the bar is evaluated at various distances outside the