HST STIS Observations of PG 0946+301: the Highest Quality UV Spectrum of a BALQSO

We describe deep (40 orbits) HST/STIS observations of the BALQSO PG 0946+301 and make them available to the community. These observations are the major part of a multi-wavelength campaign on this object aimed at determining the ionization equilibrium and abundances (IEA) in broad absorption line (BAL) QSOs. We present simple template fits to the entire data set, which yield firm identifications for more than two dozen BALs from 18 ions and give lower limits for the ionic column densities. We find that the outflow's metalicity is consistent with being solar, while the abundance ratio of phosphorus to other metals is at least ten times solar. These findings are based on diagnostics that are not sensitive to saturation and partial covering effects in the BALs, which considerably weakened previous claims for enhanced metalicity. Ample evidence for these effects is seen in the spectrum. We also discuss several options for extracting tighter IEA constraints in future analyses, and present the significant temporal changes which are detected between these spectra and those taken by the HST/FOS in 1992.Comment: 32 pages, 7 figures, to appear in ApJ. See also companion paper by Arav, Korista and De Koo

Arte, conhecimento geográfico e leitura de imagens: O geógrafo, de Vermeer Art, geographical knowledge and image reading: Vermeer's "Geographer"

O quadro O geógrafo, do pintor holandês Johannes Vermeer, é uma imagem freqüentemente escolhida para capas de livros em geografia. Desenhada na segunda metade do século XVII, a pintura não apenas pode ser considerada um retrato de como pensar e fazer geografia naquela época, mas também representa uma obra de arte com forte carga simbólica para estimular uma discussão metodológica sobre a leitura geográfica de imagens. Neste texto, objetiva-se refletir sobre as linguagens deste quadro dentro do seu contexto sociocultural, econômico e político e em relação aos diversos processos de construir conhecimento geográfico.<br>The painting The Geographer by the Dutch artist Johannes Vermeer is an image that is frequently selected as a cover for geography books. Drawn in the second half of the 17th century, the picture must not only be considered as a portrait of how to think and do geography at that time; it can also be seen as a piece of art with a heavy symbolic load to stimulate a methodological debate on geographic readings of images. The present text aims to reflect about the languages of this painting, considering its sociocultural, economic and political contexts and its relation to the different processes of constructing geographic knowledge