Matrix formulation of the energy exchange problem of multi-level systems and the code FRIGUS

@article{Coppola2019MatrixFO,
  title={Matrix formulation of the energy exchange problem of multi-level systems and the code FRIGUS},
  author={Carla Maria Coppola and Mher V. Kazandjian},
  journal={Rendiconti Lincei. Scienze Fisiche e Naturali},
  year={2019},
  volume={30},
  pages={707 - 714}
}
FRIGUS is a user-friendly Python package for computing cooling functions that depend on gas density, radiation and gas temperatures. The input data are organized as matrices and the computation of the equilibrium level population, as well as the time-dependent evolution of the level population, together with the energy exchange is reduced to matrix operations, unlike traditional methods. The compact matrix formalism makes it easy to handle multi-level and multi-quantum number systems. FRIGUS… Expand

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