Research: Extrasolar Planet Spectroscopy of Transiting Planets
What do extrasolar planets look like? What is the composition of their atmospheres? Could they harbour life? And what can we learn about extrasolar planets at all? These questions provide the motivation for my thesis in which I study the physical and obervational properties of transiting planets and their host stars. One very fruitful approach to answering the questions are spectroscopic investigations of the stellar light during the transit phase. The lines in the stellar spectrum, imprinted by the star's atmosphere on the black-body emission profile and broadened due stellar rotation by the Doppler-effect, get deformed when the planetary - or any - companion covers a certain fraction of the stellar sphere as seen from Earth. These distortions vary in time and their shape depends on the geometry of the system, its dynamics, the radii of the bodies and their temperatures. Fitting these deformed lines yields a virtual shift in radial velocity of the star relative to Earth and is known as the Rossiter-McLaughlin effect. However, this shift is not real but only mimiced by the transiting planet. My task is to simulate this effect in dependence of the mentioned parameters and, in context of extended planetary atmospheres, even on wavelength and compare this with observational data of extrasolar planet hosting stars like HD209458 and the eclipsing Brown Dwarf binary system 2MASSJ05352184-0546085.
- Heller, R., Jackson, B., Barnes, R., Greenberg, R., Homeier, D. (2010) Tidal effects on brown dwarfs: application to the eclipsing binary 2MASS J05352184-0546085. The anomalous temperature reversal in the context of tidal heating», A&A, Vol. 514, p. A22
- Heller, R., Mislis, D., Antoniadis, J. (2009) Transit detections of extrasolar planets around main-sequence stars. I. Sky maps for hot Jupiters», A&A, Vol. 508, p. 1509
- Heller, R., Homeier, D., Dreizler, S., Østensen, R. (2009) Spectral analysis of 636 WD - M star binaries from the Sloan Digital Sky Survey (Data Release 6)», JPhCS, Vol. 172, p. 012023
- Heller, R., Homeier, D., Dreizler, S., Østensen, R. (2009) Spectral analysis of 636 white dwarf-M star binaries from the sloan digital sky survey», A&A, Vol. 496, p. 191