NEW YOUNG STARS AND BROWN DWARFS IN THE UPPER SCORPIUS ASSOCIATION
K L Luhman1,2, K A Herrmann3, E E Mamajek4,5
1Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802, USA; kluhman@astro.psu.edu.
The Astronomical Journal
|January 8, 2019
Summary
Researchers expanded the census of the Upper Sco association by classifying 530 new members using spectral data. This brings the total known members to 1631, aiding future discoveries of substellar objects.
Area of Science:
- Astronomy
- Stellar Astrophysics
- Star Formation
Background:
- The Upper Sco association is a young (~11 Myr) star-forming region crucial for understanding stellar evolution.
- Previous censuses have identified numerous members but hundreds of candidates still require spectroscopic confirmation.
Purpose of the Study:
- To significantly improve the census of the Upper Sco association by identifying and confirming new members.
- To refine spectral types and membership evidence for known and suspected members.
Main Methods:
- Utilized wide-field imaging surveys for candidate selection based on parallax, proper motion, and color-magnitude diagrams.
- Obtained optical and infrared spectra for hundreds of candidates to determine spectral types and assess membership.
- Performed spectroscopy on known/suspected members to refine their classifications.
Main Results:
- Classified 530 new members of the Upper Sco association, with 377 lacking prior spectroscopic data.
- Compiled a comprehensive catalog of 1631 known members of the Upper Sco association.
- Demonstrated the effectiveness of spectroscopic follow-up for membership confirmation.
Conclusions:
- The census of the Upper Sco association has been substantially enhanced.
- Hundreds of candidates still await spectroscopic classification, highlighting the need for continued observation.
- Future data from missions like Gaia will further aid in identifying substellar members.
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