Imaging the disk around the young T Tauri star SU Aurigae
Is it possible to detect exoplanets around young active G and K dwarfs ?
A brief summary of my latest results are shown below. For a more detailed publication list please look at my publications on ADS via this link.
YES it is! Theoretical predictions suggest that the distribution of planets invery young starscould be very different to that typically observed in Gyr old systems that are thecurrent focus of radial velocity surveys. In this paper we placerealistic limitations on the possibilities for detecting planets around young active Gand K dwarfs. We conclude that Jupitermass planets canbe detected close-in around fast-rotating young active stars, Neptune-mass planetsaround moderate rotators and that Super-Earths are only detectable around veryslowly rotating stars. The effects of an increase in stellar activity jitter by observingyounger stars can be compensated for by extending the observational base-line.
In this paper we image the circumstellar environment of the young T Tauri star SU Aurigae in linearly polarised light. This technique is particularly suitable for observing the circumstellar environments of stars as it is possible to easily remove the unpolarised starlight. For SU Aurigae we interpret the images with radiative transfer model and determine that there are very small grains in the surface layers of SU Aur's disk.
Using imaging polarimetry we have imaged dust puffs around R Crb. We were fortuante to observe the star when it had emitted a dust puff along the line of sight which acted as a natural corograph. We were able to image previously emitted dust puffs
Stellar magnetic field measurements obtained from spectropolarimetry offer key data for activity and dynamo studies, and we present the results of a major high-resolutionspectropolarimetric Bcool project magnetic snapshot survey of170 solar-type stars. Surface magnetic fields were detected for 67 stars. An important result is that stars with a chromospheric S-index greater than about 0.2 show a highmagnetic field detection rate and so offer optimal targets for future studies. This survey constitutes the most extensive spectropolarimetric survey of cool starsundertaken to date.