J-PAS: unprecedented precision in stellar populations of diffuse tidal features
Abstract
Galaxies frequently interact with nearby systems, a process that can significantly alter their morphology and star formation activity. However, spectroscopic studies of their faint and diffuse remnants require very long exposure times and often exceed the limited field of view of integral field units (IFUs). On the other hand, broad-band imaging can have a much wider field of view, but lacks the spectral resolution to identify key spectral features, restricting accurate constraints on stellar population properties. With its 54 narrow-band filters in the optical and wide coverage (planned 8000 square degrees), J-PAS fills this gap. In this case study, we examine PGC 3087775, a massive galaxy at z = 0.046179 (~ 201 Mpc) in the later stages of a major merger in the J-PAS early data release. Photometry was validated with MaNGA IFU data (for the central part). Stellar population properties was derived using both J-PAS and SDSS photometry. SDSS indicates a metal-rich population with an extended star formation history (SFH) and elevated star formation rates. J-PAS instead points to a less metal-rich population with moderate extinction and a more rapid SFH, consistent with a quenched stellar population. The average Dn(4000) index of the tidal features is 1.24, suggesting that it was a non-dry merger and a fourfold improvement in the precision of stellar mass and Dn (4000) was found with J-PAS. We also assessed two heuristic methods for estimating the mass-to-light ratio from SDSS filters and found that they overestimate the stellar mass in this galaxy by 0.5 dex and 0.4 dex relative to SED fitting results from J-PAS and SDSS, respectively. Future work will extend this analysis to a larger sample of merging galaxies and evolution of the stellar populations of such structures across the nearby Universe to unprecedented detail. This project is fully reproducible, through Maneage (commit 0f0d7e2).
Cite
@article{arxiv.2603.22166,
title = {J-PAS: unprecedented precision in stellar populations of diffuse tidal features},
author = {Sepideh Eskandarlou and Mohammad Akhlaghi and Francisco Arizo-Borillo and Johan H. Knapen and Helena Domínguez Sánchez and Juan Antonio Fernández-Ontiveros and Carlos López-Sanjuan and Rosa María González Delgado and Yolanda Jiménez Teja and Renato Dupke and Yves Revaz and Pascale Jablonka and Santi Roca-Fábrega and Juan Miró-Carretero and David Martínez-Delgado and Alejandro Lumbreras-Calle and Antonio Hernán-Caballero and Héctor Vázquez Ramió and Raúl Infante-Sainz and Ana L. Chies-Santos and Alessandro Ederoclite and Julio Esteban Rodríguez Martín and Raul Abramo and Jailson Alcaniz and Narciso Benitez and Silvia Bonoli and Javier Zaragoza and Saulo Carneiro and Javier Cenarro and David Cristóbal-Hornillos and Simone Daflon and Carlos Hernández-Monteagudo and Jifeng Liu and Antonio Marín Franch and Claudia Mendes de Oliveira and Mariano Moles and Fernando Roig and Laerte Sodré and Keith Taylor and Jesús Varela and José Manuel Vilchez},
journal= {arXiv preprint arXiv:2603.22166},
year = {2026}
}
Comments
Accepted for publication in A&A. For the underlying data of the figures and tables see Appendix E. Supplementary data on Zenodo (https://doi.org/10.5281/zenodo.17674805), project source on Gitlab (https://gitlab.com/sepideh.esk/alba) and archived on Software Heritage (swh:1:dir:7c203a565ec6ef40d8419dbdf70e8639b78f4b99; see text for usage). Abstract is summarized to fit arXiv limit