The Scholl reaction was adopted to synthesize the very large polycyclic aromatic hydrocarbons (VLPAHs) hexabenzocoronene (HBC), quaterrylene and dicoronylene as well as their nonalternant isomers. These molecules can be considered subsections of a graphene sheet since the radial diameter of HBC is 13.5 Å and the length of both quaterrylene and

We present the radial velocity (RV) distribution of Carina dSph, obtained using low-, medium- and high-resolution spectroscopic data collected with FORS2 and GIRAFFE at the VLT. We found that regions where the mean RV is smaller the dispersion is also smaller, and the RV distribution is sharper (i.e. the kurtosis attains larger values). The mean RV

Recent high temporal and spatial resolution observations of the chromosphere have forced the definition of a new type of spicule, "type II's," that are characterized by rising rapidly, having short lives, and by fading away at the end of their lifetimes. Here, we report on features found in realistic three-dimensional simulations of the outer solar

We present a study of the bar fraction in the Coma cluster galaxies based on a sample of ~190 galaxies selected from the SDSS-DR6 and observed with the Hubble Space Telescope (HST) Advanced Camera for Survey (ACS). We explore the presence of bars, detected by visual classification, throughout an unprecedented luminosity range of 9 mag (- 23 Mr

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We analyse complementary Hubble Space Telescope and Subaru data for the globular cluster NGC 2419. We make a detailed analysis of the horizontal branch (HB), which is composed of two main groups of stars: the luminous blue HB stars, which extend by evolution into the RR Lyrae and red HB region, and a fainter, extremely blue population. We examine