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Related papers: Two new chemically peculiar stars with resolved ma…

200 papers

Emission lines in the eV and keV range by certain stellar candidates from their recent analysis invoke the question of their possible origin. These stars under consideration, are the 4U 0614+091 (0.65, 0.86, and 1.31 keV), 2S 0918-549 (0.8…

Astrophysics · Physics 2007-05-23 Subharthi Ray , Jishnu Dey , Mira Dey , Siddhartha Bhowmick

The spectral features of HD 94509 are highly unusual, adding an extreme to the zoo of Be and shell stars. The shell dominates the spectrum, showing lines typical for spectral types mid-A to early-F, while the presence of a late/mid B-type…

Solar and Stellar Astrophysics · Physics 2015-05-27 C. R. Cowley , N. Przybilla , S. Hubrig

We report the identification of 61.45 d^-1 (711.2 mu Hz) oscillations, with amplitudes of 62.6-mu mag, in KIC 4768731 (HD 225914) using Kepler photometry. This relatively bright (V=9.17) chemically peculiar star with spectral type A5 Vp…

We report the discovery of a new slowly pulsating B (SPB) star, with the largest number of detected frequencies to date by more than a factor of three, based on 37 days of MOST (Microvariability & Oscillations of STars) satellite guide star…

We provide detailed abundance analyses of 8 candidate super-metal-rich stars. Five of them are confirmed to have [Fe/H] > 0.2 dex, the generally-accepted limit for super-metal-richness. Furthermore, we derive abundances of several elements…

Astrophysics · Physics 2007-05-23 Sofia Feltzing , Guillermo Gonzalez

The early-type chemically peculiar stars often show strong magnetic fields on their surfaces. These magnetic topologies are organized on large scales and are believed to be close to an oblique dipole for most of the stars. In a striking…

Solar and Stellar Astrophysics · Physics 2015-05-20 Oleg Kochukhov , Andreas Lundin , Iosif Romanyuk , Dmitry Kudryavtsev

We present the results of the continuation of our magnetic survey with FORS1 at the VLT of a sample of B-type stars consisting of confirmed or candidate beta Cephei stars and Slowly Pulsating B (hereafter SPB) stars, along with a small…

Solar and Stellar Astrophysics · Physics 2009-11-13 S. Hubrig , M. Briquet , P. De Cat , M. Schoeller , T. Morel , I. Ilyin

The discovery of exotic abundances, chemical inhomogeneities, and weak magnetic fields on the surface of late B-type primaries in spectroscopic binaries has important implications not only for our understanding of the formation mechanisms…

Solar and Stellar Astrophysics · Physics 2015-06-03 S. Hubrig , J. F. Gonzalez , I. Ilyin , H. Korhonen , I. S. Savanov , T. Dall , M. Schoeller , C. R. Cowley , M. Briquet , R. Arlt

We present an analysis of high time resolution spectra of the chemically peculiar Ap star HD 213637. The star shows rapid radial velocity variations with a period close to the photometric pulsation period. Radial velocity pulsation…

Solar and Stellar Astrophysics · Physics 2015-06-23 V. G. Elkin , D. W. Kurtz , G. Mathys

Reported are spectroscopic observations of 15 candidates for Kepler primary asteroseismic targets and 14 other stars in the Kepler field, carried out at three observatories (see the footnote). For all these stars, the radial velocities,…

Solar and Stellar Astrophysics · Physics 2009-07-17 J. Molenda-Zakowicz , A. Frasca , D. W. Latham , M. Jerzykiewicz

Our understanding of the evolved, rapidly rotating, magnetically active, and apparently single FK Comae stars is significantly hindered by their extreme rarity: only two stars in addition to FK Com itself are currently considered to be…

Solar and Stellar Astrophysics · Physics 2020-06-03 James Sikora , Jason Rowe , Steve Howell , Elena Mason , Gregg A. Wade

We have determined spectroscopic orbits for five single-lined spectroscopic binaries, HD 100167, HD 135991, HD 140667, HD 158222, HD 217924. Their periods range from 60.6 to 2403 days and the eccentricities, from 0.20 to 0.84. Our spectral…

Solar and Stellar Astrophysics · Physics 2014-02-07 Francis C. Fekel , Samira Rajabi , Matthew W. Muterspaugh , Michael H. Williamson

The atmospheric structure of chemically peculiar stars deviates from that of normal stars with similar fundamental parameters due to unusual chemistry, abundance inhomogeneities and the presence of strong magnetic field. These effects are…

Astrophysics · Physics 2007-12-03 O. Kochukhov , D. Shulyak

We used three sets of high-resolution spectra acquired with the multifiber facility FLAMES at the Very Large Telescope of the European Southern Observatory to investigate the chemical and kinematical properties of a sample of 42 horizontal…

Solar and Stellar Astrophysics · Physics 2015-06-05 L. Lovisi , A. Mucciarelli , B. Lanzoni , F. R. Ferraro , R. Gratton , E. Dalessandro , R. Contreras Ramos

A number of planetary nebulae show binary central stars and significant abundance discrepancies between values estimated from colisionally excited lines when compared to the same abundances estimated from recombination lines. One approach…

Astrophysics of Galaxies · Physics 2016-12-23 H. Monteiro , J. Garcia-Rojas , D. Jones , R. Corradi , P. Rodriguez-Gil

Sulfur abundances have been determined for ten stars to resolve a debate in the literature on the Galactic chemical evolution of sulfur in the halo phase of the Milky Way. Our analysis is based on observations of the S I lines at 9212.9,…

Astrophysics · Physics 2009-11-10 N. Ryde , D. L. Lambert

Highly r-process-enhanced stars are rare and usually metal-poor ([Fe/H] < - 1.0), and mainly populate the Milky Way halo and dwarf galaxies. This study presents the discovery of a relatively bright (V = 12.72), highly r-process-enhanced…

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

A classical Local Thermodynamic Equilibrium analysis, based on high-resolution spectroscopic data, is performed for a sample of three potential barium dwarf candidates and one star already recognized as such. We derived their atmospheric…

Solar and Stellar Astrophysics · Physics 2024-02-27 M. P. Roriz , N. Holanda , L. V. da Conceição , S. Junqueira , N. A. Drake , A. Sonally , C. B. Pereira

We have proposed the new explanation of some magnetic chemically peculiar (MCP) stars anomalies, which is based on assumption that such stars can be the close binary systems with a secondary component being neutron star. Within this…

Astrophysics · Physics 2007-12-17 V. F. Gopka , O. M. Ulyanov , S. M. Andrievsky