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arXiv · 2509.12327

Exploring the spatially-resolved capabilities of the J-PAS survey with Py2DJPAS

Abstract

We present Py2DJPAS, a Python-based tool to automate the analysis of spatially resolved galaxies in the \textbf{miniJPAS} survey, a 1~deg$^2$ precursor of the J-PAS survey, using the same filter system, telescope, and Pathfinder camera. Py2DJPAS streamlines the entire workflow: downloading scientific images and catalogs, performing PSF homogenization, masking, aperture definition, SED fitting, and estimating optical emission line equivalent widths via an artificial neural network. We validate Py2DJPAS on a sample of resolved miniJPAS galaxies, recovering magnitudes in all bands consistent with the catalog ($\sim 10$~\% precision using SExtractor). Local background estimation improves results for faint galaxies and apertures. PSF homogenization enables consistent multi-band photometry in inner apertures, allowing pseudo-spectra generation without artifacts. SED fitting across annular apertures yields residuals $<10$~\%, with no significant wavelength-dependent bias for regions with $S/N>5$. We demonstrate the IFU-like capability of J-PAS by analyzing the spatially resolved properties of galaxy 2470-10239 at $z = 0.078$, comparing them to MaNGA data within 1 half-light radius (HLR). We find excellent agreement in photometric vs. spectroscopic measurements and stellar mass surface density profiles. Our analysis extends to 4 HLR (S/N~$\sim$~5), showing that J-PAS can probe galaxy outskirts, enabling the study of evolutionary processes at large galactocentric distances.

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J. E. Rodríguez-Martín, L. A. Díaz-García, R. M. González Delgado, G. Martínez-Solaeche, R. García-Benito, A. de Amorim, J. Thainá-Batista, R. Cid Fernandes, I. Márquez, A. Fernández-Soto, I. Breda, R. Abramo, J. Alcaniz, N. Benítez, S. Bonoli, S. Carneiro, A. J. Cenarro, D. Cristóbal-Hornillos, R. A. Dupke, A. Ederoclite, A. Hernán-Caballero, C. Hernández-Monteagudo, C. López-Sanjuan, A. Marín-Franch, C. Mendes de Oliveira, M. Moles, L. Sodré, K. Taylor, J. Varela, H. Vázquez Ramió. 2025-09-15. Exploring the spatially-resolved capabilities of the J-PAS survey with Py2DJPAS. https://doi.org/10.1051/0004-6361%2F202555386

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