3D Radiative Transfer Modeling of the Red Supergiant NML Cyg
Other - Master thesis report, 2021

Red supergiants are bright but cool massive stars that have depleted their core hydrogen supply and have started fusing heavier elements. These evolved stars ex- perience a strong mass loss through a slow moving stellar wind that results in an extended circumstellar envelope with a rich chemistry. The circumstellar envelopes of red supergiants will eventually enrich the interstellar medium, influencing the formation and evolution of the next generation of stars and planets. Understanding the mass loss of massive evolved stars is a key component in understanding both the evolution of individual stars and the chemical evolution of the universe.

We analyze carbon monoxide emission around the red supergiant NML Cyg ob- served with the ground based JCMT 15 meter and Onsala 20 meter telescopes, as well as the HIFI instrument aboard the Herschel Space Observatory. The line pro- files have complex shapes, suggestive of multiple components in the stellar outflow. 3D radiative transfer modeling is used to recreate the observed line profiles.

circumstellar environments


radiative transfer modeling




Per Hirvonen

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Plasma Physics and Fusion Energy

MOOSE: Molecular observations of old stellar environments

Swedish National Space Board (159/16), 2017-01-01 -- 2020-12-31.

Subject Categories

Astronomy, Astrophysics and Cosmology


Basic sciences


Onsala Space Observatory

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