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相关论文: The Abundance of Interstellar Fluorine and Its Imp…

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The source of fluorine is not well understood, although core-collapse supernovae, Wolf-Rayet stars, and asymptotic giant branch stars have been suggested. A search for evidence of the nu process during Type II supernovae is presented.…

天体物理学 · 物理学 2009-11-10 S. R. Federman , Yaron Sheffer , David L. Lambert , V. V. Smith

Observations obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) have been used to determine the column densities of D I, O I, and N I along seven sight lines that probe the local interstellar medium (LISM) at distances from 37…

We present a theoretical investigation of the chemistry of fluorine-bearing molecules in diffuse and dense interstellar gas clouds. The chemistry of interstellar fluorine is qualitatively different from that of any other element, because -…

天体物理学 · 物理学 2009-11-11 David A. Neufeld , Mark G. Wolfire , Peter Schilke

In this paper, we report on the gas-phase abundance of singly-ionized iron (Fe II) for 51 lines of sight, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE). Fe II column densities are derived by measuring the equivalent…

天体物理学 · 物理学 2010-11-05 Adam G. Jensen , Theodore P. Snow

Neutral fluorine (F I) lines are identified in the optical spectra of cool EHe stars. These are the first identification of F I lines in a star's spectrum, and provide the first measurement of fluorine abundances in EHe stars. The results…

天体物理学 · 物理学 2011-02-11 Gajendra Pandey

The interstellar abundances of D I, N I, and O I in the local ISM are studied us ing high-resolution spectra of four hot white dwarfs. The spectra of GD 246, WD 2331$-$475, HZ 21, and Lan 23 were obtained with the {\it Far Ultraviolet…

We present Far Ultraviolet Spectroscopic Explorer (FUSE) and Space Telescope Imaging Spectrograph observations of the weak interstellar N I doublet at 1160 Angstroms toward 17 high-density sight lines [N(Htot)>=10^21 cm^-2]. When combined…

天体物理学 · 物理学 2009-11-10 David C. Knauth , B-G Andersson , Stephan R. McCandliss , H. Warren Moos

We report on new FUSE far-UV spectroscopy of the most metal-poor blue compact dwarf galaxy I Zw 18. The new data represent an improvement over previous FUSE spectra by a factor of 1.7 in the signal-to-noise. Together with a larger spectral…

天体物理学 · 物理学 2009-11-07 A. Aloisi , S. Savaglio , T. M. Heckman , C. G. Hoopes , C. Leitherer , K. R. Sembach

The abundance of fluorine is determined from the (2-0) R9 2.3358 micron feature of the molecule HF for several dozen normal G and K stars in the Galactic thin disk from spectra obtained with the Phoenix IR spectrometer on the 2.1-m…

太阳与恒星天体物理 · 物理学 2015-08-19 Catherine A. Pilachowski , Cameron Pace

We present an analysis of interstellar absorption along the line of sight to the nearby white dwarf star HZ43A. The distance to this star is 68+/-13 pc, and the line of sight extends toward the north Galactic pole. Column densities of OI,…

We report on the abundance of interstellar neutral nitrogen (NI) for 30 sightlines, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope (HST). NI column densities are derived by measuring the…

天体物理学 · 物理学 2008-11-26 Adam G. Jensen , Brian L. Rachford , Theodore P. Snow

We present the first fluorine measurements in 12 normal giants belonging to the Galactic thin and thick disks using spectra obtained with the Phoenix infrared spectrometer on the 2.1m telescope at Kitt Peak. Abundances are determined from…

星系天体物理 · 物理学 2024-06-06 K. E. Brady , C. A. Pilachowski , V. Grisoni , Z. G. Maas , K. A. Nault

Far-infrared line and continuum fluxes are presented for a sample of 227 galaxies observed with the Long Wavelength Spectrometer on the Infrared Space Observatory. The galaxy sample includes normal star-forming systems, starbursts, and…

天体物理学 · 物理学 2009-11-13 James R. Brauher , Daniel A. Dale , George Helou

The chemical evolution of fluorine is investigated in a sample of Milky Way red giantstars that span a significant range in metallicity from [Fe/H] $\sim$ -1.3 to 0.0 dex. Fluorine abundances are derived from vibration-rotation lines of HF…

太阳与恒星天体物理 · 物理学 2019-11-11 Rafael Guerço , Katia Cunha , Verne V. Smith , Christian R. Hayes , Carlos Abia , David L. Lambert , Henrik Jönsson , Nils Ryde

We report interstellar FeII and SiII column densities toward six translucent sight lines (A_V >~ 1) observed with the Space Telescope Imaging Spectrograph (STIS). The abundances were determined from the absorption of SiII] at 2335…

天体物理学 · 物理学 2011-02-11 Adam Miller , J. T. Lauroesch , Ulysses J. Sofia , Stefan I. B. Cartledge , David M. Meyer

We report the first ensemble results from the FUSE survey of molecular hydrogen in lines of sight with A_V $\gtrsim$ 1 mag. We have developed techniques for fitting computed profiles to the low-J lines of H2, and thus determining column…

The cosmic origin of fluorine is still not well constrained. Several nucleosynthetic channels at different phases of stellar evolution have been suggested, but these must be constrained by observations. For this, the fluorine abundance…

With abundances and 2{\sigma} upper limits of fluorine (F) in seven metal-poor field giants, nucleosynthesis of stellar F at low metallicity is discussed. The measurements are derived from the HF(1-0) R9 line at 23358{\AA} using…

星系天体物理 · 物理学 2013-02-19 H. N. Li , H. -G. Ludwig , E. Caffau , N. Christlieb , G. Zhao

We report on the abundance of interstellar neutral oxygen (OI) for 26 sightlines, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE), the International Spectroscopic Explorer (IUE), and the Hubble Space Telescope (HST). OI…

天体物理学 · 物理学 2009-11-10 Adam G. Jensen , Brian L. Rachford , Theodore P. Snow

We present measurements of the column densities of interstellar DI and OI made with the Far Ultraviolet Spectroscopic Explorer (FUSE), and of HI made with the International Ultraviolet Explorer (IUE) toward the sdOB star Feige 110 [(l,b) =…

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