IRTF/iSHELL K-band sp. obs. of PMS stars

These spots manifest as surface thermal inhomogeneities, which alter the global temperature measured on the stars. To understand the effects and implications of these starspots, we conducted a large iSHELL high-resolution infrared spectroscopic survey of T Tauri stars in Taurus-Auriga and Ophiuchus star-forming regions.

From the K-band spectra, we measured stellar temperatures and magnetic field strengths using a magnetic radiative transfer code. We compared our infrared-derived parameters against literature optical temperatures and found (a) a systematic temperature difference between optical and infrared observations, and (b) a positive correlation between the magnetic field strengths and the temperature differences. The discrepant temperature measurements imply significant differences in the inferred stellar masses from stellar evolutionary models.