Petr Hadrava

email: had@sunstel.asu.cas.cz
phone: +420 226 258 421

Petr Hadrava is senior researcher. He works in the theory od stellar atmospheres, classical and relativistic radiative transfer and radiation hydrodynamics. He is the author of codes for solution of radial-velocity and light-curves (FOTEL) and for disentangling of spectra of multiple stars (KOREL). He is also interested in the history of medieval and renaissance astronomy.

The method of spectra disentangling, performed by the code KOREL, is a way of simultaneous decomposition of spectral components, solution of orbital elements, and 'line-photometry' of binary andmultiple stars. It enables to overcome the problem of blending spectral lines by Doppler effect due to radial motion of the binary system. Comparing spectra obtained at different orbital phases, this method fits them as a superposition of some a priori unknown spectra attributed to individual components, each one Doppler shifted for its radial velocity (which is a free parameter or is obtained independently).