SpecpolFlow: a new software package for spectropolarimetry using Python

Colin P. Folsom; Christiana Erba; Veronique Petit; Shaquann Seadrow; Patrick Stanley; Tali Natan; Bonnie Zaire; Mary E. Oksala; Federico Villadiego Forero; Robin Moore; Marisol Catalan Olais

doi:10.21105/joss.07891

arXiv · 2505.18476

SpecpolFlow: a new software package for spectropolarimetry using Python

Colin P. Folsom·Christiana Erba·Veronique Petit·Shaquann Seadrow·Patrick Stanley·Tali Natan·Bonnie Zaire·Mary E. Oksala·Federico Villadiego Forero·Robin Moore·Marisol Catalan Olais

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Abstract

Spectropolarimetry, the observation of polarization and intensity as a function of wavelength, is a powerful tool in stellar astrophysics. It is particularly useful for characterizing stars and circumstellar material, and for tracing the influence of magnetic fields on a host star and its environment. Maintaining modern, flexible, and accessible computational tools that enable spectropolarimetric studies is thus essential. The SpecpolFlow package is a new, completely Pythonic workflow for analyzing stellar spectropolarimetric observations. Its suite of tools provides a user-friendly interface for working with data from an assortment of instruments and telescopes. SpecpolFlow contains tools for spectral normalization and visualization, the extraction of Least-Squares Deconvolution (LSD) profiles, the generation and optimization of line masks for LSD analyses, and the calculation of longitudinal magnetic field measurements from the LSD profiles. It also provides Python classes for the manipulation of spectropolarimetric products. The SpecpolFlow website includes an array of tutorials that guide users through common analysis cases using the software. SpecpolFlow is distributed as a free, open-source package, with fully documented tools (via an API and command line interface) which are actively maintained by a team of contributors.

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Colin P. Folsom, Christiana Erba, Veronique Petit, Shaquann Seadrow, Patrick Stanley, Tali Natan, Bonnie Zaire, Mary E. Oksala, Federico Villadiego Forero, Robin Moore, Marisol Catalan Olais. 2025-05-24. SpecpolFlow: a new software package for spectropolarimetry using Python. https://doi.org/10.21105/joss.07891

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