Non local thermodynamical radiative transfer in red supergiant stellar atmospheres
by
Julien Lambert(Lund)
→
Europe/Stockholm
FA31
FA31
Description
Water is an important constituent of the atmosphere of red supergiant stars (RSG),
which influence remains however poorly understood. The water
spectrum of these stars can apparently be only reproduced through the addition of a
detached shell of cool molecular gas, the so-called MOLspheres. However, this
hypothesis is still cautious. In order to better interpret observed spectra, non
local thermodynamic equilibrium (NLTE) spectrum synthesis may be potentially
important. NLTE effects being potentially important, they may alleviate the
problems in the interpretation of water spectra, and affect the atmosphere
dynamics. We thus developed an original method to solve the radiative transfer
equation, adapted to the numerous water transitions and without the LTE
approximation. This method has been implemented in an original parallel code.
Preliminary results show that NLTE effects in RSG atmospheres and their impact on
observables such as the emergent spectrum are very important.
