Monitoring Inner Regions in the RY Tau Jet

Taichi Uyama, Michihiro Takami, Gabriele Cugno, Vincent Deo, Olivier Guyon, Jun Hashimoto, Julien Lozi, Barnaby Norris, Motohide Tamura, Sebastien Vievard, Hans Moritz Günther, P. Christian Schneider, Eiji Akiyama, Tracy L. Beck, Thayne Currie, Klaus Hodapp, Jungmi Kwon, Satoshi Mayama, Youichi Ohyama, Tae Soo PyoJohn P. Wisniewski

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


We present multiepoch observations of the RY Tau jet for Hα and [Fe ii] 1.644 μm emission lines obtained with the Subaru Coronagraphic Extreme-AO and Visible Aperture Masking Polarimetric Imager for Resolved Exoplanetary Structures (VAMPIRES), Gemini Near-infrared Integral Field Spectrograph, and Keck/OSIRIS in 2019-2021. These data show a series of four knots within 1″ consistent with the proper motion of ∼0.″3 yr-1, analogous to the jets associated with another few active T Tauri stars. However, the spatial intervals between the knots suggest the time intervals of the ejections of about 1.2, 0.7, and 0.7 yr, significantly shorter than those estimated for the other stars. These Hα images contrast with the archival Very Large Telescope Spectro-Polarimetric High-contrast Exoplanet Research and Zurich IMaging POLarimeter (ZIMPOL) observations from 2015, which showed only a single knot-like feature at ∼0.″25. The difference between the 2015 and 2019-2021 epochs suggests an irregular ejection interval within the six-year range. Such variations of the jet ejection may be related to a short-term (<1 yr) variability of the mass accretion rate. We compared the peaks of the Hα emissions with the ZIMPOL data taken in 2015, showing the brighter profile at the base (<0.″3) than the 2020-2021 VAMPIRES profiles due to time-variable mass ejection rates or the heating-cooling balance in the jet. The observed jet knot structures may be alternatively attributed to stationary shocks, but a higher angular resolution is required to confirm its detailed origin.

Original languageEnglish (US)
Article number268
JournalAstronomical Journal
Issue number6
StatePublished - Jun 1 2022

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'Monitoring Inner Regions in the RY Tau Jet'. Together they form a unique fingerprint.

Cite this