English
Related papers

Related papers: Line identifications in the spectrum of $\chi$ Lup…

200 papers

Observations of the Mercury-Manganese star Phi Herculis with the Navy Prototype Optical Interferometer (NPOI) conclusively reveal the previously unseen companion in this single-lined binary system. The NPOI data were used to predict a…

This study introduces a line list for the abundance analysis of F and G type stars across the 4080-9675 A wavelength range. A systematic search employing lower excitation potentials, accurate log gf values, and an updated multiplet table…

Solar and Stellar Astrophysics · Physics 2025-01-09 T. Şahin , F. Güney , S. A. Şentürk , N. Çınar , M. Marışmak

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…

Astrophysics · Physics 2011-02-11 Gajendra Pandey

We report on a detailed abundance study of the fairly bright slow rotators HD 30085 (A0 IV), HD 30963 (B9 III) and HD 174567 (A0 V), hitherto reported as normal stars and the sharp-lined chi Lupi A (B9 IV HgMn). In the spectra of HD 30085,…

Solar and Stellar Astrophysics · Physics 2019-10-02 R. Monier , E. Griffin , M. Gebran , T. Kilicoglu , T. Merle , F. Royer

We report the results of our analysis of new high resolution spectra of 37 late-F to early-G dwarf stars for the purpose of deriving their Li abundances. Most of the stars were selected from the large Valenti and Fischer compilation and had…

Solar and Stellar Astrophysics · Physics 2015-06-19 Guillermo Gonzalez

Chemically peculiar stars of the mercury-manganese (HgMn) type represent a new class of spotted late-B stars, in which evolving surface chemical inhomogeneities are apparently unrelated to the presence of strong magnetic fields but are…

The light elements, Li, Be, and B, provide tracers for many aspects of astronomy including stellar structure, Galactic evolution, and cosmology. We have taken spectra of Be in 117 metal-poor stars ranging in metallicity from [Fe/H] = -0.5…

Solar and Stellar Astrophysics · Physics 2015-05-30 Ann Merchant Boesgaard , Jeffrey A. Rich , Emily M. Levesque , Brendan P. Bowler

Phosphorus abundances of ~80 apparently bright sharp-lined early-to-late B-type stars on the upper main sequence are determined by applying the non-LTE analysis to the P II line at 6043.084 A, with an aim of getting information on the P…

Solar and Stellar Astrophysics · Physics 2024-09-05 Yoichi Takeda

Lithium abundances determined by spectral synthesis from both the 6708A resonance line and the 6104 subordinate line are reported for 11 late-type Pleiades stars, including spectra previously analysed by Russell (1996). We report a 0.7 dex…

Astrophysics · Physics 2009-11-07 A. Ford , J. Jeffries , B. Smalley

Neutral Fe lines in metal-poor stars yield conflicting abundances depending on whether and how deviations from local thermodynamic equilibrium (LTE) are considered. We have collected new high resolution and high signal-to-noise ultraviolet…

Solar and Stellar Astrophysics · Physics 2018-07-04 Ian U. Roederer , Christopher Sneden , James E. Lawler , Jennifer S. Sobeck , John J. Cowan , Ann Merchant Boesgaard

We present new abundances derived from Cu I, Cu II, Zn I, and Zn II lines in six warm (5766 < Teff < 6427 K), metal-poor (-2.50 < [Fe/H] < -0.95) dwarf and subgiant (3.64 < log g < 4.44) stars. These abundances are derived from archival…

Solar and Stellar Astrophysics · Physics 2018-04-25 Ian U. Roederer , Paul S. Barklem

We propose a line list that may be useful for the abundance analysis of G-type stars in the wavelength range 4080 -- 6780 A. It is expected that the line list will be useful for surveys/libraries with overlapping spectral regions (e.g.…

Solar and Stellar Astrophysics · Physics 2023-10-09 T. Sahin , M. Marismak , N. Cinar , S. Bilir

A non-LTE analysis of C I lines at 1.068-1.069 micron was carried out for selected 46 halo/disk stars covering a wide metallicity range (-3.7 <[Fe/H]< +0.3), based on the spectral data collected with IRCS+AO188 of the Subaru Telescope, in…

Solar and Stellar Astrophysics · Physics 2015-06-15 Yoichi Takeda , Masahide Takada-Hidai

The sharp-line spectrum of the Bp star HR 6000 has peculiarities that distinguish it from those of the HgMn stars with which it is sometimes associated. The position of the star close to the center of the Lupus 3 molecular cloud, whose…

Solar and Stellar Astrophysics · Physics 2017-05-24 F. Castelli , C. R. Cowley , T. R. Ayres , G. Catanzaro , F. Leone

We present new results on the classical T Tauri star RU Lupi based on three observing runs collecting high-resolution spectra, complementary NIR spectra, multicolour photometric data, and X-ray observations. The photospheric absorption…

Solar and Stellar Astrophysics · Physics 2015-06-17 Gösta F. Gahm , Henricus C. Stempels , Frederick M. Walter , Peter P. Petrov , Gregory J. Herczeg

We present a non-local thermodynamic equilibrium abundance analysis of the resonance doublet Li I at 6707.8 A for 55 Galactic F and G supergiants and bright giants. The derived lithium abundances log \epsilon(Li) may be considered in three…

The abundances of alkali elements (Li, Na, and K) were determined from the Li I 6708, Na I 5682/5688, and K I 7699 lines by taking into account the non-LTE effect for 24 sharp-lined A-type stars v sin i < 50 km/s, 7000 K < Teff <10000 K,…

Solar and Stellar Astrophysics · Physics 2015-06-03 Yoichi Takeda , Dong-Il Kang , Inwoo Han , Byeong-Cheol Lee , Kang-Min Kim , Satoshi Kawanomoto , Naoko Ohishi

We identified a possible origin of the difficulty in abundance analysis of cool luminous stars. We found purely empirically that there is a limit of logW/nu = -4.75 (W: equivalent width, nu: wavenumber) above which the observed lines do not…

Astrophysics · Physics 2009-11-13 Takashi Tsuji

We present the detailed modelling of line spectra emitted from galaxies at redshifts 0.2<z<2.3. The spectra account only for a few oxygen to Hb line ratios. The results show that [OII]3727+3729/Hb and [OIII]5007+4959/Hb are not sufficient…

Astrophysics of Galaxies · Physics 2015-06-18 M. Contini

We present Li abundances for 73 stars in the metallicity range -3.5 < [Fe/H] < -1.0 using improved IRFM temperatures (Casagrande et al. 2010) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Melendez , L. Casagrande , I. Ramirez , M. Asplund , W. J. Schuster
‹ Prev 1 2 3 10 Next ›