相关论文: Center-to-limb variation of spectral lines and the…
Observations of center-to-limb variations (CLV) of spectral lines and continua provide a good test for the accuracy of models of solar and stellar atmospheric structure and spectral-line formation. They are also widely used to constrain…
Line profiles from spatially unresolved stellar observations consist of a superposition of local line profiles that result from observing the stellar atmosphere under specific viewing angles. Line profile variability caused by stellar…
Transit spectroscopy is one of the most commonly used techniques for exoplanet atmosphere characterisation. This technique has been used to detect ionized and neutral species in exoplanet atmospheres by comparing the observed stellar lines…
The center-to-limb variation (CLV) describes the brightness of the stellar disk as a function of the limb angle. Across strong absorption lines, the CLV can vary quite significantly. We obtained a densely sampled time series of…
Spatially resolved observations of the Sun and the astronomical sample size of stellar bodies are the respective key strengths of solar and stellar observations. However, the large difference in object brightness between the Sun and other…
Context. Transmission spectroscopy is one of the most powerful techniques to characterize transiting exoplanets since it allows to measure the abundance of the atomic and molecular species in the planetary atmosphere. However, the stellar…
The center-to-limb variations (CLV) of transition region line Gaussian fit parameters in solar plage are reported for the first time. The Si iv 1402.77 A line observed by Interface Region Imaging Spectrograph (IRIS) is used. The spectral…
Context. Scattering and absorption processes in stellar atmosphere affect the center-to-limb variations of the intensity (CLVI) and the linear polarization (CLVP) of stellar radiation. Aims. There are several theoretical and observational…
The Sun's spectrum varies with center-to-limb distance. This variation is governed by the underlying temperature-density structure of the solar atmosphere. To explore the spectrally resolved center-to-limb variation (CLV) we make use of two…
The center-to-limb variations (CLVs) of photospheric and chromospheric spectral lines were obtained in 2025 July and August using drift scans from the echelle spectrograph of the 0.7 m Vacuum Tower Telescope at the Observatorio del Teide…
The observed center-to-limb variation (CLV) of the scattering polarization in different lines of the Second Solar Spectrum can be used to constrain the height variation of various atmospheric parameters, in particular the magnetic fields…
Stellar photospheric inhomogeneities are a significant source of noise which currently precludes the discovery of Earth-mass planets orbiting Sun-like stars with the radial-velocity (RV) method. To complement several previous studies which…
The atmospheres of exoplanets are commonly studied by observing the transit of the planet passing in front of its parent star. The obscuration of part of the stellar disk during a transit will reveal aspects of its surface structure…
One of the necessary parameters needed for the interpretation of the light curves of transiting exoplanets or eclipsing binaries, as well as interferometric measurements of a star or microlensing events is how the intensity and polarization…
We present high-resolution spectroscopic observations of the quiet-Sun center-to-limb variations (CLV) of the He I triplet at 10 830 {\AA} and the nearby Si I 10 827 {\AA} line, observed with GREGOR Infrared Spectrograph (GRIS) and the…
The ability to observe extrasolar planets transiting their stars has profoundly changed our understanding of these planetary systems. However, these measurements depend on how well we understand the properties of the host star, such as…
The transit method, employed by MOST, \emph{Kepler}, and various ground-based surveys has enabled the characterization of extrasolar planets to unprecedented precision. These results are precise enough to begin to measure planet atmosphere…
We analyze the light curves of the recent solar eclipses measured by the Herzberg channel (200-220 nm) of the Large Yield RAdiometer (LYRA) onboard PROBA-2. The measurements allow us to accurately retrieve the center- to-limb variations…
CONTEXT: The quiet Sun magnetic fields produce ubiquitous bright points (BPs) that cover a significant fraction of the solar surface. Their contribution to the total solar irradiance (TSI) is so-far unknown. AIMS: To measure the…
Unlike other stars, the surface of the Sun can be spatially resolved to a high degree of detail. But the Sun can also be observed as if it was a distant star. The availability of solar disk-resolved and disk-integrated spectra offers an…