_version_ 1866914485733687296
author Almeida-Fernandes, Felipe
Limberg, Guilherme
Perottoni, Hélio D.
Amarante, João A. S.
Bolutavicius, Guilherme F.
Cordeiro, Vinícius
Borges-Fernandes, Marcelo
Placco, Vinicius M.
da Silva, André R.
Santos-Silva, Thais
Machado-Pereira, Eduardo
Santucci, Rafael M.
Menendez-Delmestre, Karín
Gonçalves, Thiago S.
Rossi, Sílvia
Kanaan, Antônio
Schoenell, William
Ribeiro, Tiago
de Oliveira, Claudia Mendes
author_facet Almeida-Fernandes, Felipe
Limberg, Guilherme
Perottoni, Hélio D.
Amarante, João A. S.
Bolutavicius, Guilherme F.
Cordeiro, Vinícius
Borges-Fernandes, Marcelo
Placco, Vinicius M.
da Silva, André R.
Santos-Silva, Thais
Machado-Pereira, Eduardo
Santucci, Rafael M.
Menendez-Delmestre, Karín
Gonçalves, Thiago S.
Rossi, Sílvia
Kanaan, Antônio
Schoenell, William
Ribeiro, Tiago
de Oliveira, Claudia Mendes
contents We study the metallicity distribution along the Sagittarius (Sgr) stream using photometric metallicities from S-PLUS DR4, combined with Gaia DR3 kinematics and APOGEE DR17 spectroscopy. Our analysis confirms that the leading arm (Galactic latitude $b > 0$) is systematically more metal-poor than the trailing arm ($b < 0$) by 0.15--0.20 dex, and reveals a clear negative metallicity gradient along the leading arm. The trailing arm shows no significant overall gradient but displays distinct inner (negative) and outer (positive) trends. These features are consistently recovered across different photometric estimators and agree with spectroscopic data. We compare these results with predictions from an $N$-body simulation, in which metallicities were assigned according to a set of imprinted radial gradients in the progenitor. We were able to constrain the original metallicity gradient of the Sgr progenitor to be between $-0.38$ and $-0.24$ dex kpc$^{-1}$ based on photometric data, and $-0.42$ to $-0.10$ dex kpc$^{-1}$ from APOGEE. These values are consistent with gradients observed in other Local Group dwarf galaxies. Our findings demonstrate that metallicity-sensitive photometric surveys such as S-PLUS are powerful tools for reconstructing the chemodynamical evolution of disrupted satellites.
format Preprint
id arxiv_https___arxiv_org_abs_2604_16727
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The Metallicity Gradient of Sagittarius Dwarf Spheroidal Galaxy Prior to Infall Constrained by S-PLUS Observations of its Tidal Stream
Almeida-Fernandes, Felipe
Limberg, Guilherme
Perottoni, Hélio D.
Amarante, João A. S.
Bolutavicius, Guilherme F.
Cordeiro, Vinícius
Borges-Fernandes, Marcelo
Placco, Vinicius M.
da Silva, André R.
Santos-Silva, Thais
Machado-Pereira, Eduardo
Santucci, Rafael M.
Menendez-Delmestre, Karín
Gonçalves, Thiago S.
Rossi, Sílvia
Kanaan, Antônio
Schoenell, William
Ribeiro, Tiago
de Oliveira, Claudia Mendes
Astrophysics of Galaxies
We study the metallicity distribution along the Sagittarius (Sgr) stream using photometric metallicities from S-PLUS DR4, combined with Gaia DR3 kinematics and APOGEE DR17 spectroscopy. Our analysis confirms that the leading arm (Galactic latitude $b > 0$) is systematically more metal-poor than the trailing arm ($b < 0$) by 0.15--0.20 dex, and reveals a clear negative metallicity gradient along the leading arm. The trailing arm shows no significant overall gradient but displays distinct inner (negative) and outer (positive) trends. These features are consistently recovered across different photometric estimators and agree with spectroscopic data. We compare these results with predictions from an $N$-body simulation, in which metallicities were assigned according to a set of imprinted radial gradients in the progenitor. We were able to constrain the original metallicity gradient of the Sgr progenitor to be between $-0.38$ and $-0.24$ dex kpc$^{-1}$ based on photometric data, and $-0.42$ to $-0.10$ dex kpc$^{-1}$ from APOGEE. These values are consistent with gradients observed in other Local Group dwarf galaxies. Our findings demonstrate that metallicity-sensitive photometric surveys such as S-PLUS are powerful tools for reconstructing the chemodynamical evolution of disrupted satellites.
title The Metallicity Gradient of Sagittarius Dwarf Spheroidal Galaxy Prior to Infall Constrained by S-PLUS Observations of its Tidal Stream
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2604.16727