Star-crossed Lovers DI Tau A and B: Orbit Characterization and Physical Properties Determination
June 2023 • 2023ApJ...950...92T
Abstract • The stellar companion to the weak-line T Tauri star DI Tau A was first discovered by the lunar occultation technique in 1989 and was subsequently confirmed by a speckle imaging observation in 1991. It has not been detected since, despite being targeted by five different studies that used a variety of methods and spanned more than 20 yr. Here, we report the serendipitous rediscovery of DI Tau B during our Young Exoplanets Spectroscopic Survey (YESS). Using radial velocity data from YESS spanning 17 yr, new adaptive optics observations from Keck II, and a variety of other data from the literature, we derive a preliminary orbital solution for the system that effectively explains the detection and (almost all of the) non-detection history of DI Tau B. We estimate the dynamical masses of both components, finding that the large mass difference (q ~ 0.17) and long orbital period (≳35 yr) make the DI Tau system a noteworthy and valuable addition to studies of stellar evolution and pre-main-sequence models. With a long orbital period and a small flux ratio (f2/f1) between DI Tau A and B, additional measurements are needed for a better comparison between these observational results and pre-main-sequence models. Finally, we report an average surface magnetic field strength ( $\bar{B}$ ) for DI Tau A, of ~0.55 kG, which is unusually low in the context of young active stars.
Links
- PREPRINT http://arxiv.org/abs/2303.11347
- ELECTR https://doi.org/10.3847/1538-4357/acc58b
- SIMBAD https://simbad.u-strasbg.fr/simbad/sim-ref?querymethod=bib&simbo=on&submit=submit+bibcode&bibcode=2023ApJ...950...92T
- PDF https://iopscience.iop.org/article/10.3847/1538-4357/acc58b/pdf
- DATA https://irsa.ipac.caltech.edu/bibdata/2023/T/2023ApJ...950...92T.html
