Search Results - "Alecian, G"

Diffusion velocity of metals in Ap star atmospheres: the effect of ambipolar diffusion of H by Alecian, G

“…ABSTRACT Ambipolar diffusion of hydrogen is effective in the atmosphere of stars when hydrogen is partially ionized. This is precisely the case for Ap stars…”
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Abundance distributions over the surfaces of magnetic ApBp stars: theoretical predictions by Alecian, G.

“…Recently published empirical abundance maps, obtained through (Zeeman) Doppler mapping, do not currently agree with the abundance structures predicted by means…”
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Statistical analysis from recent abundance determinations in HgMn stars by Ghazaryan, S., Alecian, G.

“…To better understand the hot chemically peculiar group of HgMn stars, we have considered a compilation of a large number of recently published data obtained…”
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New catalogue of chemically peculiar stars, and statistical analysis by Ghazaryan, S, Alecian, G, Hakobyan, A A

“…In this paper, we present a new catalogue of chemically peculiar (CP) stars obtained by compiling publications in which abundances of metals are provided. Our…”
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3D distribution models of Ca, Cr, and Fe in a magnetic CP star atmosphere with anisotropic wind by Alecian, G, Stift, M J

“…ABSTRACT We present time-dependent atomic diffusion calculations for Ca, Cr, and Fe in a stellar magnetic atmosphere including an anisotropic wind. For three…”
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An improved parametric method for evaluating radiative accelerations in stellar interiors by Alecian, G, LeBlanc, F

“…ABSTRACT The single-valued parameter (SVP) method is a parametric method that offers the possibility of computing radiative accelerations in stellar interiors…”
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Time-dependent atomic diffusion in the atmospheres of CP stars. A big step forward: introducing numerical models including a stellar mass-loss by Alecian, G, Stift, M J

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Statistical analysis of roAp, He-weak, and He-rich stars by Ghazaryan, S, Alecian, G, Hakobyan, A A

“…Abstract To enlarge our data base of chemically peculiar stars, we compiled published data concerning the He-weak and He-rich stars observed by high-resolution…”
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Time-dependent atomic diffusion in magnetic ApBp stars by Stift, M. J., Alecian, G.

“…Numerical modelling of surface abundance distributions in ApBp star atmospheres constitutes a challenging astrophysical problem. This paper is intended to…”
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Modelling ApBp star atmospheres with stratified abundances consistent with atomic diffusion by Stift, M. J., Alecian, G.

“…ABSTRACT Elemental abundances have been found – both empirically and theoretically – to be stratified in the magnetic atmospheres of many chemically peculiar…”
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Time-dependent diffusion in stellar atmospheres by Alecian, G., Stift, M. J., Dorfi, E. A.

“…The chemical peculiarities of Ap stars are due to abundance stratifications produced by atomic diffusion in their outer layers. Theoretical models can predict…”
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Influence of Thermohaline Convection on Diffusion-Induced Iron Accumulation in a Stars by Théado, S, Vauclair, S, Alecian, G, LeBlanc, F

“…Atomic diffusion may lead to heavy-element accumulation inside stars in certain specific layers. Iron accumulation in the Z-bump opacity region has been…”
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Attempt to detect the granulation signature in the HgMn star HD 175640 from CoRoT light curves by Ghazaryan, S., Alecian, G., Harutyunian, H.

“…HgMn stars are affected by atomic diffusion processes. Because theoretical models based on atomic diffusion require that the atmospheres of ApBp stars have to…”
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New method for fast and easy computation of radiative accelerations in stars by LeBlanc, F., Alecian, G.

“…Accurate determination of radiative accelerations of the elements is critical when studying atomic diffusion in stars. However, the computing time necessary to…”
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New approximate formulae for radiative accelerations in stars by Alecian, G., LeBlanc, F.

“…Radiative accelerations are quantities that are crucial in the study of diffusion processes in stars. Their calculation requires the use of large atomic and…”
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Empirical chemical stratifications in magnetic Ap stars: questions of uniqueness by Stift, M. J., Alecian, G.

“…Over the last decades, modelling of the inhomogeneous vertical abundance distributions of various chemical elements in magnetic peculiar A type has largely…”
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Abundance distributions over the surfaces of magnetic ApBp stars: theoretical predictions: Figure 1 by Alecian, G.

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Radiation transfer in an inhomogeneous medium. optical depth depending on absorption coefficient by Alecian, G., Harutynian, H. A.

“…The invariance principle is applied to obtain the equations for finding the radiation field intensity in an inhomogeneous atmosphere. Though the behavior of…”
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Three-dimensional abundance distributions in ApBp star atmospheres: non-axisymmetric magnetic geometry by Alecian, G., Stift, M. J.

“…Abstract Numerical models for the atmospheres of magnetic ApBp stars have in the past dealt only with centred dipole magnetic field geometries. These models…”
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Behaviour of radiative accelerations in stars by Alecian, G., LeBlanc, F.

“…Diffusion processes are able to stratify elements in stars on time-scales shorter than the evolution time on the main sequence. According to the efficiency of…”
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