相关论文: Mapping stellar surfaces I: Degeneracies in the ro…
The Kepler target KIC 5110407, a K-type star, shows strong quasi-periodic light curve fluctuations likely arising from the formation and decay of spots on the stellar surface rotating with a period of 3.4693 days. Using an established…
The amplitude and morphology of light curves of solar-like stars change substantially with increasing rotation rate: brightness variations get amplified and become more regular, which has so far not been explained. We develop a modelling…
Stellar surface processes represent a fundamental limit to the detection of extrasolar planets with the currently most heavily-used techniques. As such, considerable effort has gone into trying to mitigate the impact of these processes on…
Context. We present a model-free method for mapping surface brightness variations. Aims. We aim to develop a method that is not dependent on either stellar atmosphere models or limb-darkening equation. This method is optimized for exoplanet…
It has been demonstrated that the time variability of a star's brightness at different frequencies can be used to infer its surface gravity, radius, mass, and age. With large samples of light curves now available from Kepler and K2, and…
Astrometric jitter noise arises when starspots on a rotating stellar surface move in and out of view, shifting the photocenter. This noise may limit our ability to detect and weigh small, sub-Neptune-sized planets around active stars. By…
The nearly continuous light curves with micromagnitude precision provided by the space mission Kepler are revolutionising our view of pulsating stars. They have revealed a vast sea of low-amplitude pulsation modes that were undetectable…
Astrometry measures shifts in a star's photocentre and can be used to detect reflex motion due to orbiting exoplanets. Brightness asymmetries (e.g. starspots) rotating in and out of view can also cause apparent motion of the photocenter,…
Photometric rotational modulations due to starspots remain the most common and accessible way to study stellar activity. In the Kepler-era, there now exists precise, continuous photometry of ~150,000 stars presenting an unprecedented…
Starspots and their movements on stellar surfaces enable investigating the mechanisms of stellar magnetic activity. Information on the spot distribution and differential rotation provide important constraints for the behaviour of stellar…
High precision photometry and spectroscopy of low-mass stars reveal a variety of properties standard stellar evolution cannot predict. Rotation, an essential ingredient of stellar evolution, is a step towards resolving the discrepancy…
We consider the problem of inferring the shape of a transiting object's silhouette from its light curve alone, without assuming a physical model for the object. We model the object as a grid of pixels which transits the star; each pixel has…
High precision photometry and spectroscopy of low-mass stars reveal a variety of properties standard stellar evolution cannot predict. Rotation, an essential ingredient of stellar evolution, is a step towards resolving the discrepancy…
Stars are not smooth. Their photosphere is covered by a granulation pattern associated with the heat transport by convection. The convection-related surface structures have different size, depth, and temporal variations with respect to the…
Nearly continuous, densely sampled, space-based photometry allows us to recover the finest details in the light variations of stars. The number of such light curves have been increasing rapidly in the last few years thanks to the extended…
In recent years, astronomical photometry has been revolutionised by space missions such as MOST, CoRoT and Kepler. However, despite this progress, high-quality spectroscopy is still required as well. Unfortunately, high-resolution spectra…
High-resolution spectroscopic measurements of OB stars are important for understanding processes like stellar evolution, but require labor-intensive observations. In contrast, photometric missions like the Transiting Exoplanet Survey…
The properties of a transiting planet's host star are written in its transit light curve. The light curve can reveal the stellar density and the limb darkening profile in addition to the characteristics of the planet and its orbit. For…
Time-domain surveys have advanced astronomical research by revealing diverse variable phenomena, from stellar flares to transient events. The scale and complexity of survey data, along with the demand for rapid classification, present…
Planetary transits provide a unique opportunity to investigate the surface distributions of star spots. Our aim is to determine if, with continuous observation (such as the data that will be provided by the Kepler mission), we can in…