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Related papers: New Insights on Interstellar Gas-Phase Iron

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We present a new iron abundance analysis of the hyper metal-poor star HE$~$1327-2326, based on Fe II lines detected in its UV spectral range for the first time. In a Cosmic Origins Spectrograph (COS) spectrum, five new Fe II lines could be…

Solar and Stellar Astrophysics · Physics 2018-08-27 Rana Ezzeddine , Anna Frebel

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…

Active galactic nuclei (AGN) have Fe II emission from the broad line region (BLR) that differs greatly in strength from object to object. We examine the role of the total and gas-phase iron abundance in determining Fe II strength. Using AGN…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Gregory A. Shields , Randi R. Ludwig , Sarah Salviander

In this study, we investigate interstellar absorption lines along the line of sight toward the galactic low-mass X-ray binary Cygnus X-2. We combine absorption line data obtained from high-resolution X-ray spectra collected with Chandra and…

We describe a new method for determining total gas-phase abundances for the Galactic ISM with minimal ionization uncertainties. For sight lines toward globular clusters containing both UV-bright stars and radio pulsars, one can measure…

Astrophysics · Physics 2009-11-13 J. Christopher Howk , Kenneth R. Sembach , Blair D. Savage

In this paper we report on the gas-phase abundance of singly-ionized magnesium (Mg II) in 44 lines of sight, using data from the Hubble Space Telescope (HST). We measure Mg II column densities by analyzing medium- and high-resolution…

Astrophysics · Physics 2010-11-11 Adam G. Jensen , Theodore P. Snow

We present an analysis of the subdwarf O star Feige 67 with a fully metal-line blanketed NLTE model atmosphere based on high-resolution Far-UV (912-2000 A) and Near-UV (2000-3400 A) spectra from new ORFEUS II echelle observations and the…

Astrophysics · Physics 2007-05-23 Jochen L. Deetjen

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…

We constrain the iron abundance in a sample of 33 low-ionization Galactic planetary nebulae (PNe) using [Fe III] lines and correcting for the contribution of higher ionization states with ionization correction factors (ICFs) that take into…

Astrophysics · Physics 2011-02-18 G. Delgado-Inglada , M. Rodriguez , A. Mampaso , K. Viironen

We study the current discrepancy between the model-predicted and measured concentrations of Fe++ and Fe3+ in ionized nebulae. We calculate a set of photoionization models, updated with the atomic data relevant to the problem, and compare…

Astrophysics · Physics 2009-11-10 Monica Rodriguez , Robert H. Rubin

[Abridged] We present Far Ultraviolet Spectroscopic Explorer (FUSE) observations of the young, compact planetary nebula (PN) SwSt 1 along the line of sight to its central star HD 167362. We detect circumstellar absorption lines from several…

Astrophysics · Physics 2009-11-10 N. C. Sterling , H. L. Dinerstein , C. W. Bowers , S. Redfield

We report results from a survey of neutral fluorine (F I) in the interstellar medium. Data from the Far Ultraviolet Spectroscopic Explorer (FUSE) were used to analyze 26 lines of sight lying both in the galactic disk and halo, including…

Astrophysics · Physics 2008-11-26 Theodore Snow , Joshua Destree , Adam Jensen

We present a study of the deuterium abundance along the extended sight line (2.7kpc) toward HD 90087 with FUSE. Both in terms of distance and column densities, HD 90087 has the longest and densest sight line observed in the Galactic disk…

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.…

Astrophysics · Physics 2009-11-10 S. R. Federman , Yaron Sheffer , David L. Lambert , V. V. Smith

Optical CCD spectra are used to determine the Fe abundances at several positions inside seven bright Galactic HII regions. The observed [FeIII] line ratios are compared with the predictions of different sets of collision strengths and…

Astrophysics · Physics 2009-11-07 M. Rodriguez

[Fe II] emission lines are prominent in the infrared (IR), and they are important diagnostic tools for radiative atomic shocks. We investigate the emission characteristics of [Fe II] lines using a shock code developed by Raymond (1979) with…

Astrophysics of Galaxies · Physics 2016-07-20 Bon-Chul Koo , John C. Raymond , Hyun-Jeong Kim

The role of optical Fe III absorption lines in B-type stars as iron abundance diagnostics is considered. To date, ultraviolet Fe lines have been widely used in B-type stars, although line blending can severely hinder their diagnostic power.…

We present an extensive analysis of the gas-phase abundances and depletion behaviors of neutron-capture elements in the interstellar medium (ISM). Column densities (or upper limits to the column densities) of Ga II, Ge II, As II, Kr I, Cd…

Astrophysics of Galaxies · Physics 2018-06-07 Adam M. Ritchey , Steven R. Federman , David L. Lambert

We report the results of the mid-infrared spectroscopy of 14 Galactic star-forming regions with the high-resolution modules of the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope. We detected [SiII] 35um, [FeII] 26um, and…

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…

Astrophysics · Physics 2008-11-26 Adam G. Jensen , Brian L. Rachford , Theodore P. Snow
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