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arXiv · 2501.10079

ELLIPSECT: A surface brightness analysis tool for GALFIT 3

Christopher Añorve·Omar Ulises Reyes-Amador·Emmanuel Ríos-López·Diego de Ramón Tadeo·Omar López-Cruz
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Abstract

EllipSect is a user-friendly analysis and measurement tool, implemented in Python, that operates on the imaging data together with the output of the widely used 2D surface-brightness fitting code GALFIT 3. It produces publication-quality figures and exportable data products to enable quantitative assessment of GALFIT 3 models and their individual components. In addition, EllipSect computes non-parametric measurements that are not provided by GALFIT 3, including the total effective radius resulting from multi-component fits, cusp radius, and the Petrosian radius. This paper provides examples and a quick guide for EllipSect.

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Christopher Añorve, Omar Ulises Reyes-Amador, Emmanuel Ríos-López, Diego de Ramón Tadeo, Omar López-Cruz. 2025-01-17. ELLIPSECT: A surface brightness analysis tool for GALFIT 3. https://doi.org/10.22201/ia.30618649e.2026.62.01.7524

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