Related papers: An Effective temperature calibration for solar typ…
External errors of effective temperatures of stars for selected libraries are estimated from data intercomparisons. It is found that the obtained errors are mainly in a good correspondence with the published data. The results may be used to…
We present angular diameters for 42 luminosity class I stars and 32 luminosity class II stars that have been interferometrically determined with the Palomar Testbed Interferometer. Derived values of radius and effective temperature are…
Sun-like stars are a new probe of variations in the fine-structure constant, $\alpha$, via the solar twins approach: velocity separations of close pairs of absorption lines are compared between stars with very similar stellar parameters,…
The discovery of true solar analogues is fundamental for a better understanding of the Sun and of the solar system. The open cluster M67 offers a unique opportunity to search for solar analogues because its chemical composition and age are…
The comprehensive knowledge of fundamental parameters of single stars is the basis of the modelling of star clusters and galaxies. Most fundamental stellar parameters of the individual components in SB2 eclipsing binaries are known with…
We aim to derive the electron temperature Te in the gas of metal-rich star-forming galaxies, which can be obtained from their ratios of auroral lines [O II]7320,7330 to nebular lines [O II]3727, in order to establish a more robust…
We propose a line list that may be useful for the abundance analysis of G-type stars in the wavelength range 4080 -- 6780 A. It is expected that the line list will be useful for surveys/libraries with overlapping spectral regions (e.g.…
We devised a straightforward procedure to derive the atmosphere fundamental parameters of stars across the different MK spectral types by comparing mid-resolution spectroscopic observations with theoretical grids of synthetic spectra.The…
Both the quality and amount of astrophysical data are steadily increasing over time owing to the improvement of telescopes and their instruments. This requires corresponding evolution of the techniques used for obtaining and analyzing the…
The determination of effective temperature for chemically peculiar (CP) stars by means of photometry is a sophisticated task due to their abnormal colours. Standard calibrations for normal stars lead to erroneous results and, in most cases…
As part of the Young Exoplanets Spectroscopic Survey (YESS), this study explores the spot variability of 13 T Tauri Stars (TTSs) in the near-infrared $H$ band, using spectra from the Immersion GRating INfrared Spectrometer (IGRINS). By…
Accurately measuring stellar parameters is a key goal to increase our understanding of the observable universe. However, current methods are limited by many factors, in particular, the biases and physical assumptions that are the basis for…
The Survey for Distant Solar Twins (SDST) aims to find stars very similar to the Sun at distances 1-4 kpc, several times more distant than any currently known solar twins and analogues. The goal is to identify the best stars with which to…
We compile a sample of Sun-like stars with accurate effective temperatures, metallicities and colours (from the UV to the near-IR). A crucial improvement is that the effective temperature scale of the stars has recently been established as…
Precise and accurate parameters for late-type (late K and M) dwarf stars are important for characterization of any orbiting planets, but such determinations have been hampered by these stars' complex spectra and dissimilarity to the Sun. We…
Stellar granulation produces radial-velocity (RV) jitter at the 1 m/s level in Sun-like stars, limiting Earth-analog detection. A route beyond this limit is to weight spectral lines according to their granulation sensitivity. We apply a…
A very slight rotation-induced latitudinal temperature variation (presumably on the order of several Kelvin) on the solar surface is theoretically expected. While recent high-precision solar brightness observations reported its detection,…
Solar twins are stars of key importance to the field of astronomy and offer a multitude of science applications. Only a small number ($\lesssim200$) of solar twins are known today, all of which are relatively close to our Sun…
We conducted high dispersion spectroscopic observations of 50 superflare stars with Subaru/HDS, and measured the stellar parameters of them. These 50 targets were selected from the solar-type (G-type main sequence) superflare stars that we…
A method for determining the effective temperature Teff of G- and K-type giants and supergiants is proposed. The method is based on the use of two photometric indices free from the interstellar absorption influence: the Q index in the UBV…