Upper Scorpius spectroscopy and photometry

DOI

We have refined the census of stars and brown dwarfs in the Upper Sco association (~10Myr, ~145pc) by (1) updating the selection of candidate members from our previous survey to include the high-precision astrometry from the second data release of Gaia, (2) obtaining spectra of a few hundred candidate members to measure their spectral types and verify their youth, and (3) assessing the membership (largely with Gaia astrometry) of 2020 stars toward Upper Sco that show evidence of youth in this work and previous studies. We arrive at a catalog of 1761 objects that are adopted as members of Upper Sco. The distribution of spectral types among the adopted members is similar to those in other nearby star-forming regions, indicating a similar initial mass function. In previous studies, we have compiled mid-infrared photometry from the Wide-field Infrared Survey Explorer and the Spitzer Space Telescope for members of Upper Sco and used those data to identify the stars that show evidence of circumstellar disks; we present the same analysis for our new catalog of members. As in earlier work, we find that the fraction of members with disks increases with lower stellar masses, ranging from 1M{sun} to ~22% for 0.01-0.3M{sun}. Finally, we have estimated the relative ages of Upper Sco and other young associations using their sequences of low-mass stars in M_G_RP__ versus G_BP_-G_RP_. This comparison indicates that Upper Sco is a factor of two younger than the {beta}Pic association (21-24Myr) according to both nonmagnetic and magnetic evolutionary models.

Cone search capability for table J/AJ/160/44/table1 (Candidate members of Upper Sco)

Cone search capability for table J/AJ/160/44/table3 (Spectroscopic data for candidate members of Upper Sco)

Cone search capability for table J/AJ/160/44/table4 (Young stars toward Upper Sco)

Cone search capability for table J/AJ/160/44/table5 (Mid-IR photometry for adopted Members of Upper Sco)

Identifier
DOI http://doi.org/10.26093/cds/vizier.51600044
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/AJ/160/44
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/160/44
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/160/44
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/AJ/160/44
Provenance
Creator Luhman K.L.; Esplin T.L.
Publisher CDS
Publication Year 2020
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Interdisciplinary Astronomy; Interstellar medium; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy