We present an analysis of the intrinsic colors and temperatures of 5–30 Myr old pre-main-sequence (pre-MS) stars using the F0- through M9-type members of nearby, negligibly reddened groups: the η Cha cluster, the TW Hydra Association, the β Pic Moving Group, and the Tucana-Horologium Association. To check the consistency of spectral types from the literature, we estimate new spectral types for 52 nearby pre-MS stars with spectral types F3 through M4 using optical spectra taken with the SMARTS 1.5 m telescope. Combining these new types with published spectral types and photometry from the literature (Johnson–Cousins BVIC, 2MASS JHKS and WISEW1, W2, W3, and W4), we derive a new empirical spectral type–color sequence for 5–30 Myr old pre-MS stars. Colors for pre-MS stars match dwarf colors for some spectral types and colors, but for other spectral types and colors, deviations can exceed 0.3 mag. We estimate effective temperatures (Teff) and bolometric corrections (BCs) for our pre-MS star sample through comparing their photometry to synthetic photometry generated using the BT-Settl grid of model atmosphere spectra. We derive a new Teff and BC scale for pre-MS stars, which should be a more appropriate match for T Tauri stars than often-adopted dwarf star scales. While our new Teff scale for pre-MS stars is within ≃100 K of dwarfs at a given spectral type for stars <G5, for G5 through K6, the pre-MS stars are ∼250 K cooler than their MS counterparts. Lastly, we present (1) a modern Teff, optical/IR color, and BC sequence for O9V-M9V MS stars based on an extensive literature survey, (2) a revised Q-method relation for dereddening UBV photometry of OB-type stars, and (3) introduce two candidate spectral standard stars as representatives of spectral types K8V and K9V.
INTRINSIC COLORS, TEMPERATURES, AND BOLOMETRIC CORRECTIONS OF PRE-MAIN-SEQUENCE STARS
Published 2013 in The Astrophysical Journal Supplement Series
ABSTRACT
PUBLICATION RECORD
- Publication year
2013
- Venue
The Astrophysical Journal Supplement Series
- Publication date
2013-07-10
- Fields of study
Physics
- Identifiers
- External record
- Source metadata
Semantic Scholar
CITATION MAP
EXTRACTION MAP
CLAIMS
- No claims are published for this paper.
CONCEPTS
- No concepts are published for this paper.