✨”Galaxy morphology in the morphometric parameter space.”
A cargo del Físico Matheus Koren (PPGFísica/FURG, Brasil).
🗓 Miércoles 6 de Mayo
⏰ 13:00 h
📍 Salón Meridiano – FCAG
¡Te esperamos!
RESUMEN
Traditional galaxy classification relies on rigid visual categories that fail to capture the continuous nature of structural evolution. The discrete nature of classical classification does not account for the structural continuity observed in modern deep surveys. This study addresses the need for an objective and interpretable framework to map galaxy morphology continuously. The main objective is to construct a physically meaningful morphological space using the EFIGI survey (Baillard et al. 2011) to quantify structural transitions. To analyze the multidimensional morphometric data, structural descriptors were extracted using the Morfometryka algorithm (Ferrari et al. 2015), focusing on the extended parameters CASGMHσψ, q, and Rp. While the Petrosian radius (Rp) and axial ratio (q) define robust, tilt-corrected physical boundaries, the remaining indices capture detailed structural nuances: Concentration (C), Asymmetry (A), and Smoothness (S) map basic shapes; Gini (G) and M track the uneven distribution of light; complexity is measured by Entropy (H) and Spirality (σψ). Unlike previous image-based approaches, Principal Component Analysis (PCA; Jolliffe 2002; Ivezić et al. 2014) was applied directly to this broad parameter space for dimensionality reduction, followed by Uniform Manifold Approximation and Projection (UMAP, McInnes et al. 2018) for topological projection in order to identify natural clusters. The methodology successfully segmented the sample into distinct macrostates, representing E/S0, spiral, and irregular systems. The results demonstrate that galaxy morphology is not a random process and this transparent approach provides a solid basis for quantifying structural dynamics in the era of large-scale automated surveys.
