B P Wakker

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We report the results of a F U SE study of high velocity O VI absorption along complete sight lines through the Galactic halo in directions toward 100 extragalactic objects and 2 halo stars. The high velocity O VI traces a variety of phenomena, including tidal interactions with the Magellanic Clouds, accretion of gas, outflowing material from the Galactic(More)
We present a study of the Lyα forest at z 0.4 from which we conclude that at least 20% of the total baryons in the universe are located in the highly-ionized gas traced by broad Lyα absorbers. The cool photoionized low-z intergalactic medium (IGM) probed by narrow Lyα absorbers contains about 30% of the baryons. We further find that the ratio of broad to(More)
Using Far Ultraviolet Spectroscopic Explorer (FUSE) and Hubble Space Telescope (HST) observations of the QSO PG 1259+593, we detect D I Lyman-series absorption in high velocity cloud Complex C, a low-metallicity gas cloud falling onto the Milky Way. This is the first detection of atomic deuterium in the local universe in a location other than the nearby(More)
Models of the chemical evolution of the Milky Way suggest that the observed abundances of elements heavier than helium ('metals') require a continuous infall of gas with metallicity (metal abundance) about 0.1 times the solar value. An infall rate integrated over the entire disk of the Milky Way of approximately 1 solar mass per year can solve the 'G-dwarf(More)
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