Related papers: Investigating stellar activity with CoRoT data and…

The Global Oscillations at Low Frequencies instrument aboard the Solar and Heliospheric Observatory has provided over two decades of continuous, high-precision data, enabling detailed measurements of the Sun's oscillation frequencies. These…

The space experiment CoRoT has recently detected a transiting hot Jupiter in orbit around a moderately active F-type main-sequence star (CoRoT-Exo-4a). This planetary system is of particular interest because it has an orbital period of…

We report intensive monitoring of the activity variability in the H$\alpha$ line for 10 Sun-like stars using the 1.88-m reflector at Okayama Branch Office, Subaru Telescope, during the last four years 2019-2022. Our aim was to investigate…

Our study focuses on analysing the coronal, transition and chromospheric activity of four rapidly rotating stars located within 50 pc in the solar neighbourhood. We have used the multi-wavelength capabilities of AstroSat, to investigate the…

We have measured transit times for HD 189733b passing in front of its bright (V = 7.67) chromospherically active and spotted parent star. Nearly continuous broadband optical photometry of this system was obtained with the MOST…

We examine 4 years of Kepler 30-min data, and 5 Sectors of TESS 2-min data for the dM3 star KIC-8507979/TIC-272272592. This rapidly rotating (P=1.2 day) star has previously been identified as flare active, with a possible long-term decline…

We present an asteroseismic analysis of 33 solar-type stars observed in short cadence during Campaigns (C) 1-3 of the NASA K2 mission. We were able to extract both average seismic parameters and individual mode frequencies for stars with…

We present the analysis of the CoRoT star 105288363, a new Blazhko RR Lyrae star of type RRab (f0 = 1.7623 c/d), observed with the CoRoT space craft during the second long run in direction of the galactic center (LRc02, time base 145 d).…

In the search for planets orbiting distant stars the presence of stellar activity in the atmospheres of observed stars can obscure the radial velocity signal used to detect such planets. Furthermore, this stellar activity contamination is…

The dependence of stellar magnetic activity on stellar parameters would be inspired by the chromospheric activity studies based on the large-scale spectroscopic surveys. The Ca II H and K lines are employed to construct indicators for…

We present the results obtained with the CoRoT satellite for HD 50870, a Delta Sct star which was observed for 114.4 d. The 307,570 CoRoT datapoints were analysed with different techniques. The photometric observations were complemented…

CoRoT-2a is a young (about 0.5 Gyr) G7V star accompanied by a transiting hot-Jupiter, discovered by the CoRoT satellite (Alonso et al. 2008; Bouchy et al. 2008). An analysis of its photospheric activity, based on spot modelling techniques…

We present analysis of the starspot properties and chromospheric activity on HD 134319 using high precision photometry by TESS in sectors 14-16 (T1), 21-23 (T2) and high-resolution spectroscopy by OHP/ELODIE and Keck/HIRES during years…

In recent years it has been claimed that the length of stellar activity cycles is determined by the stellar rotation rate. It is observed that the cycle period increases with rotation period along the so-called active and inactive…

We analyzed the star HD 171219, one of the relatively bright Be stars observed in the seismo field of the CoRoT satellite, in order to determine its physical and pulsation characteristics. Classical Be stars are main-sequence objects of…

Studying the internal structure of exoplanets-host stars compared to that of similar stars without detected planets is particularly important for the understanding of planetary formation. The observed overmetallicity of stars around which…

The evolved main-sequence Sun-like stars KIC 10273246 (F-type) and KIC 10920273 (G-type) were observed with the NASA Kepler satellite for approximately ten months with a duty cycle in excess of 90%. Such continuous and long observations are…

Studying the internal structure of exoplanets-host stars compared to that of similar stars without detected planets is particularly important for the understanding of planetary formation. The observed overmetallicity of stars with planets…

Red Giant stars host solar-like oscillations which have mixed character, being sensitive to conditions both in the outer convection zone and deep within the interior. The properties of these modes are sensitive to both core rotation and…

Context: Recently, the CoRoT target HD 175272 (F5V), which shows a weak signal of solar-like oscillations, was modelled by a differential asteroseismic analysis (Ozel et al. 2013) relative to a seismically similar star, HD 181420 (F2V), for…