DH Tauri explained

DH Tauri, also known as DH Tau, is a type M star, located 140 parsecs (456.619 light years) away. It forms a binary system with DI Tauri away, and has a substellar companion, either a brown dwarf or massive exoplanet.

Characteristics

DH Tauri is a type M, or red dwarf star, one of the most common types of star in the Milky Way. It has an apparent magnitude of 13.71 and temperature of . DH Tauri has a mass of and an estimated radius of .

The companion DH Tauri B or b has a mass estimated to be between and, making it either a super-Jupiter or brown dwarf.[1] Other sources give a mass as high as, with a bolometric luminosity of . The spectral type has been classified as M7.5 or M9.25. The companion has detected water vapor and carbon monoxide in its atmosphere and has a rotational velocity of 9.6 ± 0.7 km/s. This is between 9 and 15% of the breakup speed of DH Tau B. This low rotation is in agreement with magnetic coupling to a circumplanetary disk in the late stages of accretion, which reduces angular momentum of the companion. The companion, while its host star still having a protoplanetary disk, is still accreting material, being surrounded by a circumsubstellar disk (possibly a circumplanetary disk, depending on its formation history). It is potentially orbited by a smaller candidate companion DH Tauri Bb (possibly an exomoon) with, and a mass ratio with respect to the brown dwarf of one-tenth.[2]

Notes and References

  1. Itoh . Yoichi . Hayashi . Masahiko . Tamura . Motohide . Tsuji . Takashi . Oasa . Yumiko . Fukagawa . Misato . Hayashi . Saeko S. . Naoi . Takahiro . Ishii . Miki . Mayama . Satoshi . Morino . Jun-ichi . Yamashita . Takuya . Pyo . Tae-Soo . Nishikawa . Takayuki . Usuda . Tomonori . 2005-02-20 . A Young Brown Dwarf Companion to DH Tauri . The Astrophysical Journal . en . 620 . 2 . 984–993 . astro-ph/0411177 . 2005ApJ...620..984I . 10.1086/427086 . 0004-637X.
  2. Lazzoni . C. . etal . 20 July 2020 . The search for disks or planetary objects around directly imaged companions: A candidate around DH Tau B . Astronomy & Astrophysics . 641 . A131 . 10.1051/0004-6361/201937290 . 2007.10097. 2020A&A...641A.131L . 220647289 .