Table · dataset · 2008
Low-mass stars in the Upper Sco association
Listed in IVOA Registry (Virtual Observatory)
The Upper Scorpius association is the OB association nearest to the Sun (145pc).
Description
Its young age (~5Myr) makes it an ideal place to search for low-mass stars and brown dwarfs, as these objects should be relatively bright. We have performed a photometric search for the low-mass members of the association, using the R, I, and Z filters.
The completeness limit is I~18.5, and the saturation limit is I~13. We obtain 138 candidate members, covering nearly the entire M spectral type range. We find an excess of brown dwarf candidates over the number predicted by a Miller-Scalo initial mass function.
Read the rest (2 more)
In addition, we have performed infrared imaging and low-resolution optical spectroscopy of selected candidates. We find that the infrared observations confirm the spectral types obtained with the optical photometry. Furthermore, we find H{alpha} in emission in 20 of the 22 objects observed spectroscopically.
As H{alpha} is an indicator of youth, we believe that these 20 objects may belong to the association. One of them, UScoCTIO 128, has a very strong and constant H{alpha} line (equivalent width -130{AA}), and its position in the color-magnitude diagram suggests that it is a brown dwarf with mass 0.02M_{sun}_. Confirmation of this and the other candidates will have to wait for higher resolution observations that can reveal spectroscopic mass indicators such as LiI and gravity indicators such as KI and the subordinate lines of NaI.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/120/479 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 2000AJ....120..479A ui.adsabs.harvard.edu/abs/2000AJ....120..479A ↗
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/aj/120/479 ↗
catalogue entry · from IVOA Registry
Topics
- Stated by source
- Optical
- From keywords
- Astronomy & Astrophysics
- Inferred from text
- Imaging 75%
Provenance · 1 source records, 9 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/aj/120/479 | 15 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| 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 | |
| concepts[modality].local:modality:imaging | enrichment · IVOA Registry | keyword-concept-rules@1.0.0 | title+description (75%) |
| 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 |