A self-consistent empirical model atmosphere, abundance and stratification analysis of the benchmark roAp star $\alpha$ Circini

  title={A self-consistent empirical model atmosphere, abundance and stratification analysis of the benchmark roAp star \$\alpha\$ Circini},
  author={Oleg Kochukhov and Denis V. Shulyak and Tatiana Ryabchikova},
  journal={Astronomy and Astrophysics},
Context. Chemically peculiar (CP) stars are unique natural laboratories for the investigation of the microscopic diffusion processes of chemical elements. The element segregation under the influenc ... 
A theoretical tool for the study of radial velocities in the atmospheres of roAp stars
Over the last decade, significant amounts of high-spectral and time-resolution spectroscopic data have been acquired for a number of rapidly oscillating Ap stars (roAp). Progress in the understandi
A self-consistent chemically stratified atmosphere model for the roAp star 10 Aquilae
Context. Chemically peculiar A-type (Ap) stars are a subgroup of the CP2 stars that exhibit anomalous overabundances of numerous elements, e.g. Fe, Cr, Sr, and rare earth elements. The pulsating
Abundance and stratification analysis of the chemically peculiar star HD 103498
The slow rotation and the absence of strong mixing processes in the atmospheres of chemically peculiar stars develop the ideal conditions for the appearance of abundance anomalies through the
Realistic model atmosphere and revised abundances of the coolest Ap star HD 101065
Aims. Among the known Ap stars, HD 101065 is probably one of the most interesting objects, demonstrating very rich spectra of rare-earth elements (REE). Strongly peculiar photometric parameters of
Orbital parameters, chemical composition, and magnetic field of the Ap binary HD 98088 ⋆
ABSTRACT HD 98088 is a synchronised, double-lined spectroscopic binary system with a mag-netic Ap primary component and an Am secondary component. We study this raresystem using high-resolution
Fundamental parameters of bright Ap stars from wide-range energy distributions and advanced atmospheric models
Aims. As a well-established procedure for the vast majority of normal main-sequence stars, determination of atmospheric and stellar parameters turns to be a challenging process in case of magnetic
Time-dependent diffusion in stellar atmospheres
The chemical peculiarities of Ap stars are due to abundance stratifications produced by atomic diffusion in their outer layers. Theoretical models can predict such stratifications, but so far only
A 3-D look into the atmosphere?
Abstract The atmospheres of chemically peculiar stars can be highly structured in both the horizontal and vertical dimensions. While most prevalent in the magnetic stars, these structures can also
Fundamental parameters and evolutionary status of the magnetic chemically peculiar stars HD 188041 (V1291 Aquilae), HD 111133 (EP Virginis), and HD 204411: spectroscopy versus interferometry
The determination of fundamental parameters of stars is one of the main tasks of astrophysics. For magnetic chemically peculiar stars, this problem is complicated by the anomalous chemical
Investigation of the dependence of rare-earth element abundances on the effective temperature and magnetic field in the atmospheres of chemically peculiar (Ap) stars
We have derived the abundances of the rare-earth elements (REEs) Ce, Pr, Nd, and Eu in the atmospheres of 26 magnetic peculiar (Ap) stars in the range of effective temperatures 7000–10 000 K from


Abundance structure of the atmospheres of magnetic CP stars
A review of the recent results on abundance and stratification analysis of the magnetic CP stars is presented. It includes a brief description of the methods as well as a comparison between the
Cosmic Abundances as Records of Stellar Evolution and Nucleosynthesis in honor of David L. Lambert
We review our current knowledge of the solar chemical composition as determined from photospheric absorption lines. In particular we describe the recent significant revisions of the solar abundances
Grids for the determination of effective temperature and surface gravity of B, A and F stars using uvby-beta photometry
Comparaison des couleurs synthetiques et des indices de photometrie uvbyβ calcules pour des atmospheres stellaires modeles avec les couleurs et indices observes pour des etoiles B, A et F dont on
Abundances and chemical stratification analysis in the atmosphere of Cr-type Ap star HD 204411
We present results of an abundance and stratification analysis of the weakly magnetic chemically peculiar star HD 204411 based on the echelle spectrum obtained with the high resolution spectrograph
Model atmospheres of magnetic chemically peculiar stars - A remarkable strong-field Bp SiCrFe star HD 137509
Context. In the last few years we have developed stellar model atmospheres which included effects of anomalous abundances and strong magnetic field. In particular, the full treatment of a nomalous
Chemical stratification in the atmosphere of Ap star HD 133792. Regularized solution of the vertical inversion problem
Context. High spectral resolution studies of cool Ap stars reveal conspicuous anomalies of the shape and strength of many absorption lines. This is a signature of large atmospheric chemical gradients
Diffusion in the Atmospheres of Blue Horizontal-Branch Stars.
The stratified models provide much better agreement with many observational features [jump in the (u, u-y) color-magnitude diagram, gaps, lower spectroscopic gravities] in comparison with classical horizontal-branch models.
Abundance stratification and pulsation in the atmosphere of the roAp star $\boldmath\gamma$ Equulei
We present the evidence for abundance stratication in the atmosphere of the rapidly oscillating Ap star Equ. Ca, Cr, Fe, Ba, Si, Na seem to be overabundant in deeper atmospheric layers, but normal to
Measurements of hyperfine structure in Mn ii
Hyper®ne structure can have a signi®cant effect on the accuracy of astrophysical determinations of chemical abundances, and absolute wavenumbers are useful for line identi®cation and solar
Stellar model atmospheres with abundance stratification
Context. Atomic diffusion is believed to be an important physical process in the atmospheres of several types of stars. Stellar atmospheres, including the stratification of the elements due to