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Related papers: The solar nitrogen abundance under the LTE assumpt…

200 papers

The abundance of holmium (Z = 67) in the Sun remains uncertain. The photospheric abundance, based on lines of Ho II, has been reported as +0.26 +/- 0.16 (on the usual scale where log(H) = 12.00), while the meteoretic value is +0.51 +/-…

Astrophysics · Physics 2015-06-24 Donald J. Bord , Charles R. Cowley

The Sloan Digital Sky Survey (SDSS) has proved to be a powerful resource for understanding the physical properties and chemical composition of star-forming galaxies in the local universe. The SDSS population of active galactic nuclei (AGN)…

Astrophysics of Galaxies · Physics 2020-06-17 Sophia R. Flury , Edward C. Moran

We present high S/N spectroscopy of 15 emission-line galaxies (ELGs) cataloged in the KPNO International Spectroscopic Survey (KISS), selected for their possession of high equivalent width [O III] lines. The primary goal of this study was…

Astrophysics of Galaxies · Physics 2015-08-19 Alec S. Hirschauer , John J. Salzer , Fabio Bresolin , Ivo Saviane , Irina Yegorova

We present high-resolution spectroscopic observations of the \ion{Li}{1} resonance line in a sample of 62 stars that belong to 31 common-proper motion pairs with twin F or G-type components. Photospheric abundances of lithium were derived…

Astrophysics · Physics 2009-11-07 Eduardo L. Martin , Gibor Basri , Yakiv Pavlenko , Yuri Lyubchik

We test our knowledge of the atomic opacity in the solar UV spectrum. Using the atomic data compiled in Paper I from modern, publicly available, databases, we perform calculations that are confronted with space-based observations of the…

Astrophysics · Physics 2009-11-07 C. Allende Prieto , I. Hubeny , D. L. Lambert

We report on non-LTE Ne abundances for a sample of B-type stellar members of the Orion Association. The abundances were derived by means of non-LTE fully metal-blanketed model atmospheres and extensive model atoms with updated atomic data.…

Astrophysics · Physics 2009-11-11 Katia Cunha , Ivan Hubeny , Thierry Lanz

HARPS spectra with signal-to-noise ratios S/N > 600 at 6000 A were analysed with MARCS model atmospheres to obtain 1D LTE abundances of C, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Sr, and Y for 72 nearby solar-type stars with metallicities in…

Solar and Stellar Astrophysics · Physics 2020-08-19 P. E. Nissen , J. Christensen-Dalsgaard , J. R. Mosumgaard , V. Silva Aguirre , E. Spitoni , K. Verma.

We present the first reliable determination of chemical abundances in an AGN outflow. The abundances are extracted from the deep and simultaneous FUSE and HST/STIS observations of Mrk 279. This data set is exceptional for its high…

Experimental work with solar neutrinos has illuminated the properties of neutrinos and tested models of how the sun produces its energy. Three experiments continue to take data, and at least seven are in various stages of planning or…

Nuclear Experiment · Physics 2009-11-11 R. G. H. Robertson

Measurements on the isotopic and elemental compositions of meteorites, planets, lunar samples, the solar wind, and solar flares since 1960 suggest that the standard solar model may be in error. A new solar model suggests that the observed…

Astrophysics · Physics 2007-05-23 O. Manuel , Aditya Katragada

The present study of spectra of twelve metal-rich cool dwarf stars, carefully selected in order to cover a range of temperatures (~4400 - 6000 K), is a follow up on Feltzing & Gustafsson (1998, A&AS 129, 237) with the aim to understand the…

Astrophysics · Physics 2007-05-23 P. Thoren , S. Feltzing

The solar photospheric Fe abundance has been determined using realistic ab initio 3D, time-dependent, hydrodynamical model atmospheres. The study is based on the excellent agreement between the predicted and observed line profiles directly…

Astrophysics · Physics 2007-05-23 M. Asplund , AA. Nordlund , R. Trampedach , R. F. Stein

Atmospheric parameters and chemical compositions for ten stars with metallicities in the region of -2.2< [Fe/H] <-0.6 were precisely determined using high resolution, high signal to noise, spectra. For each star the abundances, for 14 to 27…

Future and on-going infrared and radio observatories such as JWST, METIS or ALMA will increase the amount of rest-frame IR spectroscopic data for galaxies by several orders of magnitude. While studies of the chemical composition of the ISM…

Astrophysics of Galaxies · Physics 2022-10-19 Borja Pérez-Díaz , Enrique Pérez-Montero , Juan A. Fernández-Ontiveros , José M. Vílchez

We explore the effect of the magnetic field when using realistic three-dimensional convection experiments to determine solar element abundances. By carrying out magnetoconvection simulations with a radiation-hydro code (the Copenhagen…

Solar and Stellar Astrophysics · Physics 2015-05-19 D. Fabbian , E. Khomenko , F. Moreno-Insertis , Å. Nordlund

We take a fresh look at the abundance of nitrogen in DLAs with oxygen abundances between 1/10 and 1/100 of solar. This is a metallicity regime poorly sampled in the local universe and where QSO absorbers may hold clues to both the…

Astrophysics · Physics 2009-11-07 Max Pettini , Sara L. Ellison , Jacqueline Bergeron , Patrick Petitjean

We investigate sulphur abundance in 74 Galactic stars by using high resolution spectra obtained at ESO VLT and NTT telescopes. For the first time the abundances are derived, where possible, from three optical multiplets: Mult. 1, 6, and 8.…

Astrophysics · Physics 2009-11-11 E. Caffau , P. Bonifacio , R. Faraggiana , P. Francois , R. G. Gratton , M. Barbieri

Aims: we seek to provide additional tests of the line formation of theoretical 3D solar photosphere models. In particular, we set out to test the spatially-resolved line formation at several viewing angles, from the solar disk-centre to the…

Solar and Stellar Astrophysics · Physics 2015-05-14 Tiago M. D. Pereira , Dan Kiselman , Martin Asplund

Context: In studies of the solar spectrum relative to spectra of solar twin stars, it has been found that the chemical composition of the Sun seems to depart systematically from those of the twins. One possible explanation is that the…

Solar and Stellar Astrophysics · Physics 2015-05-30 Dan Kiselman , Tiago Pereira , Bengt Gustafsson , Martin Asplund , Jorge Meléndez , Kai Langhans

Context. Abundances of s- and r-process elements in Sun-like stars constrain nucleosynthesis in extreme astrophysical events, such as compact binary mergers and explosions of highly magnetised rapidly rotating massive stars. Aims. We…

Solar and Stellar Astrophysics · Physics 2024-01-25 N. Storm , P. S. Barklem , S. A. Yakovleva , A. K. Belyaev , P. Palmeri , P. Quinet , K. Lodders , M. Bergemann , R. Hoppe