Table · dataset · 2025
Sagittarius stream with RRLs from Gaia DR3
Listed in IVOA Registry (Virtual Observatory)
The Sagittarius (Sgr) dwarf spheroidal galaxy is one of the most prominent satellites of the Milky Way (MW).
Description
It is currently undergoing tidal disruption, forming an extensive stellar stream that provides key insights into the assembly history of the MW halo. Our goal is to investigate the structure and metallicity distribution of the Sgr stream using RR Lyrae stars (RRLs).
We analyzed RRLs provided in Gaia Data Release 3 (DR3), for which new estimates of photometric metallicities are available in the literature, and accurate distances were calculated using the reddening-free period-Wesenheit-metallicity (PWZ) relation in the Gaia G, G BP , and GRP bands. We determine the mean metallicity of RRLs in the Sgr stream to be [Fe/H]=-1.62+/-0.01dex. We measure a metallicity gradient as a function of stripping time from the Sgr progenitor of 0.05+/-0.02dex/Gyr, indicating that the metal-poor RRLs were stripped earlier during the accretion process.
Read the rest (2 more)
The far arm is found to be the most metal-poor structure of the Sgr stream, with a mean metallicity of [Fe/H]=-1.98+/-0.37dex, significantly lower than that of the leading (-1.69+/-0.31dex) and trailing (-1.64+/-0.28dex) arms. Our findings show that the RRLs in the far arm of the Sgr stream exhibit a bimodal metallicity distribution with peaks at [Fe/H]=-2.4dex and -1.7dex. The main body of the stream is the most metal-rich structure, with a mean metallicity of [Fe/H]=-1.58+/-0.31dex and a radial gradient of -0.008+/-0.005 dex/kpc.
We find almost negligible metallicity gradients of (-0.2+/-0.3)x10^-3^dex/deg in the trailing arm and (-1.0+/-0.5)x10^-3^dex/deg in the leading arm, in agreement with previous studies. Finally, we investigate the bifurcation of the Sgr stream and conclude that the metallicity difference between the faint and bright branches is not confirmed based on the RRLs in our sample.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/701/A228 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 2025A&A...701A.228M ui.adsabs.harvard.edu/abs/2025A%26A...701A.228M ↗
publication · from IVOA Registry
Catalogue records · 2
- VOResource record dc.g-vo.org/oai.xml?verb=GetRecord&metadataPrefix=ivo_vor&identifier=ivo%3… ↗
metadata API · from IVOA Registry
- Registry record (GAVO) dc.g-vo.org/I/cds.vizier/j/a%2Ba/701/a228 ↗
catalogue entry · from IVOA Registry
Topics
- Stated by source
- Optical
- From keywords
- Astronomy & Astrophysics
- Inferred from text
- Astronomical sciences 69%
Provenance · 1 source records, 9 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/a+a/701/a228 | 14 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[field].anzsrc:group:5101 | enrichment · IVOA Registry | taxonomy-embedding@1.1.0 | title+keywords+description (69%) |
| concepts[field].local:field:astronomy | mapping · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:optical | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| description | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_description |
| license_text | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| publication_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| title | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_title |
| updated_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 |