The solar photospheric abundance of carbon.Analysis of atomic carbon lines with the CO5BOLD solar model

The use of hydrodynamical simulations, the selection of atomic data, and the computation of deviations from local thermodynamical equilibrium for the analysis of the solar spectra have implied a downward revision of the solar metallicity. We are in the process of using the latest simulations computed with the CO5BOLD code to reassess the solar chemical composition. We determine the solar photospheric carbon abundance by using a radiation-hydrodynamical CO5BOLD model, and compute the departures from local thermodynamical equilibrium by using the Kiel code. We measure equivalent widths of atomic CI lines on high resolution, high signal-to-noise ratio solar atlases. Deviations from local thermodynamic equilibrium are computed in 1D with the Kiel code. Our recommended value for the solar carbon abundance, relies on 98 independent measurements of observed lines and is A(C)=8.50+-0.06, the quoted error is the sum of statistical and systematic error. Combined with our recent results for the solar oxygen and nitrogen abundances this implies a solar metallicity of Z=0.0154 and Z/X=0.0211. Our analysis implies a solar carbon abundance which is about 0.1 dex higher than what was found in previous analysis based on different 3D hydrodynamical computations. The difference is partly driven by our equivalent width measurements (we measure, on average, larger equivalent widths with respect to the other work based on a 3D model), in part it is likely due to the different properties of the hydrodynamical simulations and the spectrum synthesis code. The solar metallicity we obtain from the CO5BOLD analyses is in slightly better agreement with the constraints of helioseismology than the previous 3D abundance results. (Abridged)Comment: Astronomy and Astrophysics, accepte

Distribution of the Bari-I transposable element in stable hybrid strains between Drosophila melanogaster and Drosophila simulans and in Brazilian populations of these species

We analyzed the distribution of the Bari-I transposable element in Drosophila melanogaster (IN(1)AB), its sibling species Drosophila simulans (C167.4) and in eight hybrid strains derived from initial crosses involving D. simulans females and D. melanogaster males of the above cited strains as well as in Brazilian populations of these species. Polymerase chain reaction (PCR) data showed the presence of the Bari-I element among species populations and hybrid strains. Hybridization with a 703 bp probe homologous to the Bari-I sequence showed that the number of Bari-I copies in D. melanogaster IN(1)AB was higher than in D. simulans C167.4 strains. Hybrid strains presented Bari-I sequences related to both parental species. In addition some strains displayed a Bari-I sequence that came from D. melanogaster, suggesting introgression of D. melanogaster genetic material in the background of D. simulans. In contrast, some hybrids showed deletions of D. simulans Bari-I sequences