Browsing by Author "Dall, T. H."

Now showing 1 - 3 of 3
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    On the abundances of GRO J1655-40
    (2007) Foellmi, C.; Dall, T. H.; Depagne, E.
    Context. The detection of overabundances of alpha-elements and lithium in the secondary star of a black- hole binary provides important insights about the formation of a stellar-mass black- hole alpha-enhancement might theoretically also be the result of pollution by the nucleosynthesis occurring during an outburst, or through spallation by the jet. Aims. We study the abundances, and their possible variations with time, in the secondary star of the runaway black- hole binary GRO J1655 - 40, in order to understand their origin.
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    On the distance of GRO J1655-40
    (2006) Foellmi, C.; Depagne, E.; Dall, T. H.; Mirabel, I. F.
    Aims. We challenge the accepted distance of 3.2 kpc of GRO J1655-40. We present VLT-UVES spectroscopic observations to estimate the absorption toward the source, and determine a maximum distance of GRO J1655-40.
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    VSOP
    (2007) Dall, T. H.; Foellmi, C.; Pritchard, J.; Lo Curto, G.; Prieto, C. Allende; Bruntt, H.; Amado, P. J.; Arentoft, T.; Baes, M.; Depagne, E.; Fernandez, M.; Ivanov, V.; Koesterke, L.; Monaco, L.; O'Brien, K.; Sarro, L. M.; Saviane, I.; Scharwaechter, J.; Schmidtobreick, L.; Schuetz, O.; Seifahrt, A.; Selman, F.; Stefanon, M.; Sterzik, M.
    Context. About 500 new variable stars enter the General Catalogue of Variable Stars (GCVS) every year. Most of them however lack spectroscopic observations, which remains critical for a correct assignement of the variability type and for the understanding of the object.