Related papers: How stellar activity affects the size estimates of…
The photospheric spot activity of some of the stars with transiting planets discovered by the CoRoT space experiment is reviewed. Their out-of-transit light modulations are fitted by a spot model previously tested with the total solar…
From an observational standpoint, stellar activity poses a critical challenge to exoplanet science, as it inhibits the detection of planets and the precise measurement of their parameters. Radial velocity and transit searches revealed a…
Exoplanet host star activity, in the form of unocculted star spots or faculae, alters the observed transmission and emission spectra of the exoplanet. This effect can be exacerbated when combining data from different epochs if the stellar…
New discoveries of transiting extrasolar planets are reported weekly. Ground based surveys as well as space borne observatories like CoRoT and Kepler are responsible for filling the statistical voids of planets on distant stellar systems. I…
[Abridged] Context. Stellar activity is an important source of systematic errors and uncertainties in the characterization of exoplanets. Most of the techniques used to correct for this activity focus on an ad hoc data reduction. Aims. We…
We consider the effects of mutual transits by extrasolar planet-companion systems (in a true binary or a planet-satellite system) on light curves. We show that induced changes in light curves depend strongly on a ratio between a…
Several studies have shown that the occultation of stellar active regions by the transiting planet can generate anomalies in the high-precision transit light curves, and these anomalies may lead to an inaccurate estimate of the planetary…
The activity levels of stars are influenced by several stellar properties, such as stellar rotation, spectral type and the presence of stellar companions. In analogy to binaries, planetary companions are also thought to be able to cause…
The light curve of an exoplanetary transit can be used to estimate the planetary radius and other parameters of interest. Because accurate parameter estimation is a non-analytic and computationally intensive problem, it is often useful to…
We analyze variations in the transit lightcurves of CoRoT-2b, a massive hot Jupiter orbiting a highly active G star. We use one transit lightcurve to eclipse-map a photospheric spot occulted by the planet. In this case study we determine…
The light curve of an exoplanetary transit can be used to estimate the planetary radius and other parameters of interest. Because accurate parameter estimation is a non-analytic and computationally intensive problem, it is often useful to…
Transits of hot Jupiters in X-rays and the ultraviolet have been shown to be both deeper and more variable than the corresponding optical transits. This variability has been attributed to hot Jupiters having extended atmospheres at these…
It has been proposed that magnetic activity could be enhanced due to interactions between close-in massive planets and their host stars. In this article, I present a brief overview of the connection between stellar magnetic activity and…
Transmission spectroscopy during planetary transits, which is based on the measurements of the variations of planet-to-star radius ratio as a function of wavelength, is a powerful technique to study the atmospheric properties of transiting…
This paper examines how to compare stellar limb-darkening coefficients evaluated from model atmospheres with those derived from photometry. Different characterizations of a given model atmosphere can give quite different numerical results…
Transits of exoplanets across cool stars contain blended information about structures on the stellar surface and about the planetary body and atmosphere. To advance understanding of how this information is entangled, a surface-flux…
Main-sequence stars earlier than spectral type ~F6 or so are expected to rotate rapidly due to their radiative exteriors. This rapid rotation leads to an oblate stellar figure. It also induces the photosphere to be hotter (by up to several…
High-energy observations of the Sun provide an opportunity to test the limits of our ability to accurately measure properties of transiting exoplanets in the presence of stellar activity. Here we insert transits of a hot Jupiter into…
Research into light curves from stars (temporal variation of brightness) has completely changed how exoplanets are discovered or characterised. This study including star light curves from the Kepler dataset as a way to discover exoplanets…
We analyze the surface structure of the planet host star CoRoT-2a using a consistent model for both the `global' (i.e., rotationally modulated) lightcurve and the transit lightcurves, using data provided by the CoRoT mission. Selecting a…