Related papers: A Revised Effective Temperature Scale for the Kepl…
To assess the current status in the theoretical modeling of the spectral properties of late-type giants, we provide a comparison of synthetic photometric colors of late-type giants (calculated with PHOENIX, MARCS and ATLAS model…
We present an asteroseismic study of the solar-like stars KIC 11395018, KIC 10273246, KIC 10920273, KIC 10339342, and KIC 11234888 using short-cadence time series of more than eight months from the Kepler satellite. For four of these stars,…
The ratio of the depths of spectral lines is a powerful indicator of the effective temperature. The method based on this analysis is capable of discerning small temperature variations of individual stars. We apply this spectroscopic data…
We investigate the optical spectral region of spectra of 1000 stars searching for IMF-sensitive features to constrain the low-mass end of the initial mass function (IMF) slope in elliptical galaxies. We use the MILES stellar library in the…
In this work, a mass-effective temperature-surface gravity relation (MTGR) is developed for main sequence stars in the range of 6400 K < $T_{\rm eff}$ < 20000 K with log$g$ > 3.44. The MTGR allows the simple estimation of the masses of…
In this paper, we use the Mappings photoionization code to explore the physical parameters that impact on the measurement of electron temperature and abundance in HII regions. In the previous paper we presented observations and measurements…
We present results from spectroscopic follow-up observations of stars identified in the Kepler field and carried out by teams of the Kepler Follow-Up Observation Program. Two samples of stars were observed over six years (2009-2015): 614…
We present atmospheric parameters for 51 nearby FG dwarfs uniformly distributed over the -2.60 < [Fe/H] < +0.20 metallicity range that is suitable for the Galactic chemical evolution research. Lines of iron, Fe I and Fe II, were used to…
Red giants in the updated APOGEE-Kepler catalogue, with estimates of mass, chemical composition, surface gravity and effective temperature, have recently challenged stellar models computed under the standard assumption of solar calibrated…
We present a comparative study of effective temperatures determined from the hydrogen Balmer lines and from the UV energy distribution for 140 DA white dwarfs drawn from the IUE archive. Our results indicate that the optical and UV…
The Kepler mission has been providing high-quality photometric data leading to many breakthroughs in the exoplanet search and in stellar physics. Stellar magnetic activity results from the interaction between rotation, convection, and…
There is a well-known stellar parameter discrepancy for late K and M dwarfs, in that the observed radii and temperatures are often respectively larger and cooler than predicted by theory by several percent. In an on-going effort to…
We present a high-resolution spectroscopic analysis of two samples of evolved stars selected in the field and in the intermediate-age open cluster IC 4651, for which detailed measurements of chemical composition were made in the last few…
We use moderate-resolution optical spectrophotometry and the new MARCS stellar atmosphere models to determine the effective temperatures of 74 Galactic red supergiants. From these we find a new effective temperature scale that is…
We present empirical calibrations that estimate stellar metallicity, effective temperature and surface gravity as a function of Lick/IDS indices. These calibrations have been derived from a training set of 261 stars for which (1)…
In this study, we performed a homogeneous analysis of the planets around FGK dwarf stars observed by the Kepler and K2 missions, providing spectroscopic parameters for 310 K2 targets -- including 239 Scaling K2 hosts -- observed with…
The technique of line depth ratios (LDR) is one of the methods to determine the effective temperature of a star. They are crucial in the spectroscopic studies of variable stars like Cepheids since no simultaneous photometry is usually…
We present Keck HIRES spectra of 6 late-M dwarfs and 11 L dwarfs. Our goal is to assign effective temperatures to the objects using detailed atmospheric models and fine analysis of the alkali resonance absorption lines of CsI and RbI. These…
We present the results of a medium resolution optical spectroscopic survey of 92 cool ($3,000 \lesssim T_{\rm eff} \lesssim 4,500\,$K) southern TESS candidate planet hosts, and describe our spectral fitting methodology used to recover…
We analyze physical characteristics of late-type stars wherein the Kepler mission registered superflares. We use the revised stellar fundamental parameters, i.e. effective temperatures Teff and surface gravitational accelerations log g,…