English
Related papers

Related papers: Chemical abundances for A-and F-type supergiant st…

200 papers

We present elemental abundance results for HE 2148-2039 and HE 2155-2043 based on a detailed high-resolution spectroscopic analysis. The high-resolution SUBARU/HDS spectra used for our analysis have a resolution of R~60 000. Although…

Solar and Stellar Astrophysics · Physics 2021-05-12 Meenakshi Purandardas , Aruna Goswami

We present detailed chemical analyses for a sample of twelve stars selected from the CH star catalogue of Bartkevicius (1996). The sample includes two confirmed binaries, four objects that are known to show radial velocity variations and…

Solar and Stellar Astrophysics · Physics 2014-12-12 Drisya Karinkuzhi , Aruna Goswami

We present the results of time-resolved photometry, abundance analysis and Doppler imaging of an Ap star, HD 100357. The {\it TESS} photometry revealed rotational modulation with a period of 1.6279247 days. Upon inspecting the residuals…

We present detailed chemical compositions of four stars on the first-ascent red giant branch that are classified as chemically peculiar, but lack comprehensive analyses at high spectral resolution. For BD+03{\deg}2688, HE 0457-1805, HE…

Solar and Stellar Astrophysics · Physics 2022-11-30 M. P. Roriz , C. B. Pereira , S. Junqueira , M. Lugaro , N. A. Drake , C. Sneden

Based on the second Gaia data release (DR2) and APOGEE (DR16) spectroscopic surveys, wedefined two kinds of star sample: high-velocity thick disk (HVTD) with $v{\phi}>90km/s$ and metal-richstellar halo (MRSH) with $v{\phi}<90km/s$. Due to…

Astrophysics of Galaxies · Physics 2021-07-07 Haifan Zhu , Cuihua Du , Yepeng Yan , Jianrong Shi , Jun Ma , Heidi Jo Newberg

A comprehensive abundance analysis providing rare insight into the chemical history of lead stars is still lacking. We present results from high resolution (R ~ 50000), spectral analyses of three CH stars, HD 26, HD 198269, HD 224959, and,…

Solar and Stellar Astrophysics · Physics 2015-11-11 Aruna Goswami , Wako Aoki , Drisya Karinkuzhi

The hydrogen-deficiency in extremely hot post-AGB stars of spectral class PG1159 is probably caused by a (very) late helium-shell flash or a AGB final thermal pulse that consumes the hydrogen envelope, exposing the usually-hidden intershell…

Solar and Stellar Astrophysics · Physics 2015-05-14 K. Werner

We perform a detailed elemental abundance study of the early-type B star HD 28248 and estimate its orbital path in the Galaxy. From the comparison of spectroscopic observations performed at the European Southern Observatory at La Silla in…

Solar and Stellar Astrophysics · Physics 2015-06-11 Ronaldo S. Levenhagen , Roseli Künzel , Nelson V. Leister

Parameters and abundances for 1002 stars of spectral types F, G, and K of luminosity class IV and V have been derived. After culling the sample for rotational velocity and effective temperature, 867 stars remain for discussion. Twenty-eight…

Solar and Stellar Astrophysics · Physics 2016-12-28 R. Earle Luck

We have used high-resolution, high-S/N ratio spectra from the UVES spectrograph at the ESO VLT telescope. Long-term radial-velocity measurements and broad-band photometry allow us to determine improved orbital elements and stellar…

We have obtained high-resolution, high signal-to-noise spectra for 899 F and G dwarf stars in the Solar neighbourhood. The stars were selected on the basis of their kinematic properties to trace the thin and thick discs, the Hercules…

Astrophysics of Galaxies · Physics 2015-05-13 T. Bensby , S. Feltzing

Context: Asteroseismology, a powerful approach for obtaining internal structure and stellar properties, requires surface temperature and chemical composition information to determine mass and age. High-resolution spectroscopy is a valuable…

Solar and Stellar Astrophysics · Physics 2024-01-19 Nagaraj Vernekar , Sara Lucatello , Angela Bragaglia , Andrea Miglio , Nicoletta Sanna , Gloria Andreuzzi , Antonio Frasca

Coude spectroscopic data of a poorly-studied peculiar supergiant, HD327083, are presented. Halpha and Hbeta line profiles have been fitted employing a non-LTE code adequate for spherically expanding atmospheres. Line fits lead to estimates…

Astrophysics · Physics 2009-11-06 M. A. D. Machado , F. X. de Araujo , S. Lorenz-Martins

Hot subluminous stars can be spectroscopically classified as subdwarf B (sdB) and O (sdO) stars. While the latter are predominantly hydrogen deficient, the former are mostly helium deficient. The atmospheres of most sdOs are almost devoid…

Solar and Stellar Astrophysics · Physics 2019-10-09 Matti Dorsch , Marilyn Latour , Ulrich Heber

Despite its mean apparent magnitude of m(v)=6.39, the evolutionary status of HD190390 (HR7671), a luminous F-type supergiant at high galactic latitude, is still not very clear, but in most papers a post-AGB classification is assumed. New…

Astrophysics · Physics 2007-05-23 Maarten Reyniers , Jan Cuypers

High-resolution, high-signal-to-noise (<S/N> = 85) spectra have been obtained for five stars -- CD-24:17504, CD-38:245, CS 22172-002, CS 22885-096, and CS 22949-037 -- having [Fe/H] < -3.5 according to previous lower S/N material. LTE…

Astrophysics · Physics 2009-11-06 John E. Norris , Sean G. Ryan , Timothy C. Beers

HD 65949 is a late B star with exceptionally strong Hg II at 3984[A], but it is not a typical HgMn star. The Re II spectrum is of extraordinary strength. Abundances, or upper limits are derived here for 58 elements based on a model with…

Solar and Stellar Astrophysics · Physics 2016-08-14 C. R. Cowley , S. Hubrig , P. Palmeri , P. Quinet , É. Biémont , G. M. Wahlgren , O. Schütz , J. F. González

We present the results of an abundance analysis for a sample of stars with $-4<$[Fe/H]$<-2$. The data were obtained with the HIRES spectrograph at Keck Observatory. The set includes 28 stars, with effective temperature ranging from 4800 to…

The formation of dust gaps in protoplanetary disks is one of the most important signposts of disk evolution and possibly the formation of planets. We aim to characterize the 'flaring' disk structure around the Herbig Ae/Be stars HD 100453…

Solar and Stellar Astrophysics · Physics 2016-04-20 S. Khalafinejad , K. M. Maaskant , N. Marinas , A. G. G. M Tielens

We report the results of a coherent study of three chemically anomalous metal-poor ([Fe/H] ~ -2) stars. These objects exhibit unusually low abundances of Mg, Si, Ca (alpha-elements) and Sr, Y, and Ba (neutron-capture elements). Our analyses…

‹ Prev 1 3 4 5 6 7 10 Next ›