相关论文: Temperature stratification of the atmosphere of Ar…

Synthetic spectra of Arcturus computed with the latest theoretical stellar atmospheres disagree strongly with both the spectral energy distribution and with the spectroscopic data for $\lambda < 4000$ \AA , even though the stellar…

Absorption lines of the 12CO and 13CO molecular bands (Delta v = 2) at 2.29 -- 2.45 micron are modelled in spectrum of Arcturus (K2III). We compute a grid of model atmospheres and synthetic spectra for giant of Teff = 4300, log g = 1.5, and…

The outer atmosphere of K giants shows thermally inhomogeneous structures consisting of the hot chromospheric gas and the cool molecular gas. We present spectro-interferometric observations of the multicomponent outer atmosphere of the…

We report detections of pure rotation lines of OH and H2O in the K1.5 III red-giant star Arcturus (alpha Bootis) using high-resolution, infrared spectra covering the regions 806-822 cm-1 (12.2-12.4 um) and 884-923 cm-1 (10.8-11.3 um).…

We derive a self-consistent set of atmospheric parameters and abundances of 17 elements for the red giant star Arcturus: Teff = 4286+/-30 K, logg = 1.66+/-0.05, and [Fe/H] = -0.52+/-0.04. The effective temperature was determined using model…

Abundance of iron in the atmosphere of Arcturus has been determined from the profiles or regions of the profiles of the weak lines sensitive to iron abundance. The selected lines of Fe I and Fe II were synthesized with the MARCS theoretical…

In this talk I presented and discussed our unexpected detection of water vapor in the disk-averaged spectrum of the K2IIIp red giant Arcturus [for details, see Ryde et al. (2002)]. Arcturus, or alpha Bootes is, with its effective…

The extended wings of the Ca II H and K lines provide excellent diagnostics of the temperature stratification of the photosphere of the Sun and of other cool stars, thanks to their LTE opacities and source functions and their large span in…

We study infrared spectrum of Arcturus to clarify the nature of the cool component of its atmosphere, referred to as the CO-mosphere, with the use of the IR spectral atlas by Hinkle et al.(1995). The nature of CO lines shows an abrupt…

We investigate the ability of both LTE and Non-LTE models to fit the near UV band absolute flux distribution and individual spectral line profiles of three standard stars for which high quality spectrophotometry and high resolution…

This paper is an H band interferometric examination of Arcturus, a star frequently used as a spatial and spectral calibrator. Using the IOTA 3 telescope interferometer, we performed spectro-interferometric observation (R~35) of Arcturus.…

We present a radiative transfer analysis of latitudinally resolved H (1.487-1.783 micron) and K (2.028-2.364 micron) band spectra of Uranus, from which we infer the distributions of aerosols and methane in the planet's atmosphere. Data were…

The synthetic spectra of MgH lines was computed for the grid of the model atmospheres and compared with observed spectrum of Arcturus. The parameters of the atmosphere of Arcturus log g=1.5 for Teff=4300 K were found by using the…

The problem on heating the atmospheres of T Tauri stars by radiation from an accretion shock has been solved. The structure and radiation spectrum of the emerging so-called hot spot have been calculated in the LTE approximation. The…

We have obtained ultra-high quality spectra (R=180,000; S/N>300) with unprecedented wavelength coverage (4400 to 7400 A) for a number of stars covering most of the HR diagram in order to test the predictions of models of stellar surface…

We present near-IR interferometric measurements of the K1.5 giant Arcturus (alpha Bootis), obtained at the IOTA interferometer with the FLUOR instrument, in four narrow filters with central wavelengths ranging from 2.03 to 2.39 micron.…

We present plane-parallel and spherical LTE and NLTE atmospheric models of a variety of stellar parameters of the red giant star Arcturus (alpha Boo, HD124897, HR5340) and study their ability to fit the measured absolute flux distribution.…

Context. Departures from local thermodynamic equilibrium (LTE) distort the calcium abundance derived from stellar spectra in various ways, depending on the lines used and the stellar atmospheric parameters. The collection of atomic data…

We modelled the H-band spectrum obtained with the Infrared Imaging Spectrograph (IRIS2) at the Anglo-Australian Telescope in order to infer the cloud structure and composition of the atmosphere of the planet between 0.1 and 11 bar. Such…

We present multidimensional non-LTE radiative transfer models of hydrogen and helium line profiles formed in the accretion flows and the outflows near the star-disk interaction regions of classical T Tauri stars (CTTSs). The statistical…