Is T Tauri North a "Classical" T Tauri Star?
Abstract
We present high-resolution H- and K-band spectroscopic observations of the archetypal T Tauri star T Tau North. Synthetic spectral modeling is used to derive the K-band temperature, surface gravity, magnetic field strength, and rotational velocity for this star. The K-band spectroscopic temperature measured is ${T}_{K \mbox{-} \mathrm{band}}=3976\pm 90\,{\rm{K}}$ , which is $\sim 1000\,{\rm{K}}$ cooler than the temperature measured from optical observations. Our K-band temperature measurement for T Tau N is confirmed using equivalent-width line ratio versus temperature relations in the H band, from which a ${T}_{H \mbox{-} \mathrm{band}}=4085\pm 155\,{\rm{K}}$ is derived. This optical versus IR temperature difference is interpreted as cool or hot spots, or both, covering a significant part of the surface of T Tau N. The gravity derived for T Tau N, $\mathrm{log}g=3.45\pm 0.14$ , is lower than the gravity of nearly every other star in a sample of 24 classical T Tauri stars in Taurus. Combining these temperature and gravity results with magnetic stellar evolutionary models, we find the age of T Tau N to be less than 1 Myr old. These results suggest that T Tau N is in an earlier evolutionary stage than most classical T Tauri stars in Taurus, arguing that it is a protostar ejected from the embedded southern binary system shortly after its formation.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 2020
- DOI:
- 10.3847/1538-4357/ab9e67
- arXiv:
- arXiv:2006.10139
- Bibcode:
- 2020ApJ...898..109F
- Keywords:
-
- Near infrared astronomy;
- Star formation;
- Pre-main sequence stars;
- Stellar magnetic fields;
- High resolution spectroscopy;
- Spectroscopy;
- Radiative transfer;
- Starspots;
- Protostars;
- 1093;
- 1569;
- 1290;
- 1610;
- 2096;
- 1558;
- 1335;
- 1572;
- 1302;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 18 pages, 9 figures, 3 tables