相关论文: Non-Local Thermodynamic Equilibrium Transmission S…

Several results indicate that the atmospheric temperature of the ultra-hot Jupiter KELT-9b in the main line formation region is a few thousand degrees higher than predicted by self-consistent models. We test whether non-local thermodynamic…

Ultra-hot Jupiters (UHJs) undergo intense irradiation by their host stars and are expected to experience non-local thermodynamic equilibrium (NLTE) effects in their atmospheres. Such effects are computationally intensive to model but, at…

We model the atmosphere of the ultra-hot Jupiter (UHJ) WASP-178b accounting for NLTE effects and compare synthetic transmission spectra with NUV and optical observations. We use the HELIOS code (LTE) in the lower and the Cloudy code (LTE or…

Physically realistic models of stellar spectra are needed in a variety of astronomical studies, from the analysis of fundamental stellar parameters, to studies of exoplanets and stellar populations in galaxies. Here we present a new version…

We aim at extracting the transmission spectrum of the HI Balmer lines of the ultra-hot Jupiter (UHJ) KELT-20b/MASCARA-2b from observations and to further compare the results with what obtained through forward modelling accounting for…

Red supergiants with their enormous brightness at J-band are ideal probes of cosmic chemical composition. It is therefore crucial to have realistic models of radiative transfer in their atmospheres, which will permit determination of…

Most of the physical information about astrophysical objects is obtained via the analysis of their electromagnetic spectra. Observed data coupled with radiation transfer models in physical conditions representative of stars, planets,…

We investigated the reliability of our silicon atomic model and the influence of non-local thermodynamical equilibrium (NLTE) on the formation of neutral silicon (Si I) lines in the near-infrared (near-IR) H-band. We derived the…

Non-local thermodynamic equilibrium (NLTE) effects in diagnostically important solar Fe I lines are important due to the strong sensitivity of Fe I to ionizing UV radiation, which may lead to a considerable under-population of the Fe I…

The hydrogen and water molecules respond very differently to the collisional-radiative processes taking place in planetary atmospheres. Naturally, the question arises whether H2O-rich atmospheres are more (or less) resilient to long-term…

Context. B-type supergiants are versatile tools to address various astrophysical topics, ranging from stellar atmospheres over stellar and galactic evolution to the cosmic distance scale. Aims. A hybrid non-LTE approach - line-blanketed…

One of the major tasks in interpretation of data from large-scale stellar surveys is to determine the fundamental atmospheric parameters such as effective temperature, surface gravity, and metallicity. In most on-going and upcoming…

Supernovae, with their diversity of compositions, velocities, envelope masses, and interactions are good testing grounds for probing the importance of NLTE in expanding atmospheres. In addition to treating H, He, Li I, O I, Ne I, Na I, and…

The recent announcement that sodium absorption has been observed in the atmosphere of HD209458b, the only EGP observed to transit its parent star, is the first direct detection of an EGP atmosphere. We explore the possibility that neutral…

Present observational techniques provide stellar spectra with high resolution at a high signal-to-noise ratio over the complete wavelength range -- from the far infrared to the X-ray. NLTE effects are particularly important for hot stars,…

The current analysis is dedicated to a detailed investigation of the non-Local Thermodynamic Equilibrium (NLTE) effects influencing the formation of the Fe I 6173 A line, which is widely used by many instruments including the Helioseismic…

We test our knowledge of the atomic opacity in the solar UV spectrum. Using the atomic data compiled in Paper I from modern, publicly available, databases, we perform calculations that are confronted with space-based observations of the…

Subdwarf B (sdB) stars are core helium-burning stars with stratified atmospheres. Their atmospheres are dominated by hydrogen (H) while the helium (He) and metal abundances are shaped by an interplay of gravitational settling and radiative…

Oxygen is a constituent of many of the most abundant molecules detected in exoplanetary atmospheres and a key ingredient for tracking how and where a planet formed. In particular, the OI 777.4 nm triplet is used to probe airglow and aurora…

We present the transmission spectra of the hot-Jupiter HD209458b taken with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. Our analysis combines data at two resolutions and applies a complete pixel-by-pixel…