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arXiv · 2607.26243

ForMoSA: Forward Modeling tool for Spectral Analysis

ForMoSA Collaboration·Simon Petrus·Paulina Palma-Bifani·Matthieu Ravet·Allan Denis·Bhavesh Rajpoot·Mickaël Bonnefoy·Gaël Chauvin·Arthur Vigan·Alice Radcliffe·Pablo Requeijo·Kevin Hoy
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Abstract

ForMoSA (FORward MOdeling tool for Spectral Analysis) is an open-source Python package to fit spectroscopic and photometric observations using a Bayesian framework. It can utilize different self-consistent atmospheric models to perform robust parameter space exploration. It has been mainly designed for fitting directly imaged young planetary-mass brown dwarfs and exoplanets. The developments within ForMoSA are supported by an international collaboration of several laboratories in France (IPAG, LIRA, LAM, and Lagrange), Germany (MPIA), USA (NASA Goddard), and Chile (FCLA, Universidad Diego Portales, and Universidad de Chile). The evolution of the code and the growing interest from the scientific community has led to the need for this dedicated publication alongside the release of ForMoSA v2.0, which has been refactored into a class architecture with user-friendly features and extended functionalities.

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ForMoSA Collaboration, Simon Petrus, Paulina Palma-Bifani, Matthieu Ravet, Allan Denis, Bhavesh Rajpoot, Mickaël Bonnefoy, Gaël Chauvin, Arthur Vigan, Alice Radcliffe, Pablo Requeijo, Kevin Hoy. 2026-07-28. ForMoSA: Forward Modeling tool for Spectral Analysis. https://arxiv.org/abs/2607.26243

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