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Related papers: HR8844: A new hot Am star ?

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Using one archival high dispersion high quality spectrum of HR 7098 (A0V) obtained with the \'echelle spectrograph SOPHIE at Observatoire de Haute Provence, we show that this star is not a superficially normal A0V star as hitherto thought.…

Solar and Stellar Astrophysics · Physics 2017-09-25 R. Monier , M. Gebran , F. Royer , T. Kılıcoğlu

While monitoring a sample of apparently slowly rotating superficially normal early A stars, we have discovered that HR 8844 (A0 V), is actually a new Chemically Peculiar star. We have first compared the high resolution spectrum of HR 8844…

Solar and Stellar Astrophysics · Physics 2018-02-21 R. Monier , M. Gebran , F. Royer , T. Kilicoglu , Y. Frémat

We describe the early results of an investigation into the spectral characteristics of the hottest Am stars (A0 - A2) in an attempt to link the HgMn and Am classes of chemical peculiarity. A limited sample of hot-Am stars was searched for…

Astrophysics · Physics 2007-05-23 Glenn M. Wahlgren , Linus Dolk

Using high-dispersion, high-quality spectra of HD 30085 obtained with the echelle spectrograph SOPHIE at Observatoire de Haute Provence, we show that this star contains strong lines of the s-process elements Sr II, Y II and Zr II. Line…

Solar and Stellar Astrophysics · Physics 2015-07-06 R. Monier , M. Gebran , F. Royer , R. E. M. Griffin

We have detected four new HgMn stars, while monitoring a sample of apparently slowly rotating superficially normal bright late B and early A stars in the northern hemisphere. Important classification lines of Hg II and Mn II are found as…

Solar and Stellar Astrophysics · Physics 2015-05-27 R. Monier , M. Gebran , F. Royer

We test the capabilities of 0.4 m telescopes equipped with an \'{e}chelle spectrograph to derive fundamental parameters and elemental abundances of four late-B type stars: HR 342, HR 769, HR 1284, and HR 8705. The medium resolution…

Solar and Stellar Astrophysics · Physics 2024-10-01 T. Kılıçoğlu , R. Monier

Using high dispersion high quality spectra of HD 30963 obtained with the echelle spectrograph SOPHIE at Observatoire de Haute Provence in November 2015, we show that this star, hitherto classified as a B9 III superficially normal star, is…

Solar and Stellar Astrophysics · Physics 2016-09-13 R. Monier , M. Gebran , F. Royer

We present a detailed analysis of seven young stars observed with the spectrograph SOPHIE at the Observatoire de Haute-Provence for which the chemical composition was incomplete or absent in the literature. For five stars, we derived the…

Solar and Stellar Astrophysics · Physics 2016-01-06 E. Caffau , A. Mott , M. Steffen , P. Bonifacio , K. G. Strassmeier , A. Gallagher , R. Faraggiana , L. Sbordone

Direct imaging suggests that there is a Jovian exoplanet around the primary A-star in the triple-star system HD131399. We investigate a high-quality spectrum of the primary component HD131399A obtained with FEROS on the ESO/MPG 2.2m…

Solar and Stellar Astrophysics · Physics 2017-07-26 N. Przybilla , P. Aschenbrenner , S. Buder

The strongest absorption features with the lower-level excitation potentials $\chi_{\rm low}<1$ eV are found to be split in the high-resolution optical spectra of the post-AGB star V354 Lac taken in 2007--2008. Main parameters,…

Solar and Stellar Astrophysics · Physics 2015-05-13 V. G. Klochkova , V. E. Panchuk , N. S. Tavolganskaya

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 have gathered high resolution echelle spectra for more than two dozen high-velocity metal-poor field stars, including BD+80 245, a star previously known to have extremely low [alpha/Fe] abundances, as well as G4-36, a new low-alpha star…

Astrophysics · Physics 2007-05-23 Inese I. Ivans , Bruce Carney , Luisa de Almeida , Chris Sneden

The majority of massive stars are located in binary or multiple star systems. Compared to single stars, these objects pose additional challenges to quantitative analyses based on model atmospheres. In particular, little information is…

Solar and Stellar Astrophysics · Physics 2024-11-27 Patrick Aschenbrenner , Norbert Przybilla

Abundances of about 18 elements including the heavy elements Y and Zr are determined from Hubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectra of seven extreme helium stars (EHes): LSE 78, BD+10 2179, V1920 Cyg,…

Astrophysics · Physics 2016-08-30 Gajendra Pandey , David L. Lambert , C. Simon Jeffery , N. Kameswara Rao

We present a detailed model-atmosphere analysis of ZNG 4, a UV-bright star in the globular cluster M13. From the analysis of a high resolution ($ R \approx 45,000 $) spectrum of the object, we derive the atmospheric parameters to be $\rm…

Astrophysics · Physics 2009-11-10 S. Ambika , M. Parthasarathy , W. Aoki , T. Fujii , Y. Nakada , Y. Ita , H. Izumiura

We have obtained a UVES spectrum of a slowly rotating strongly magnetic Ap star, HD 144897, that exhibits very large overabundances of rare-earth elements. Here we present a detailed spectral analysis of this object, also taking into…

Astrophysics · Physics 2009-11-11 T. Ryabchikova , A. Ryabtsev , O. Kochukhov , S. Bagnulo

We have determined the abundances of several chemical elements in the atmosphere of HD 87240, a member of the young open cluster NGC 3114. We have used the code ATLAS9 to compute a model atmosphere for HD 87240 for the effective temperature…

Solar and Stellar Astrophysics · Physics 2018-10-11 V. Wellenreiter , R. Monier , L. Fossati

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

Late-type stars are the most abundant in the galactic stellar population. These stars, with a similar internal structure to the Sun, are expected to have solar-like atmospheres. Investigating the stellar parameters and chemical abundances…

Since its discovery about 50 years ago, HD144941 has generally been classified as a peculiar member of the extreme helium (EHe) supergiant stars, a very rare class of low-mass hydrogen-deficient stars. We report the detection of a strong…

Solar and Stellar Astrophysics · Physics 2021-10-22 N. Przybilla , L. Fossati , C. S. Jeffery
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