2026-08-25 アリゾナ大学
A real image of disk winds carrying out molecular hydrogen gas from a planet-forming disk located about 450 light-years from us. The white line is the plane of the planet-forming disk, while the bright yellow, orange, pink and purple represent ejected gas. Naman Bajaj/JWST/MIRI-IFU
＜関連情報＞
- https://news.arizona.edu/news/planet-formation-race-against-time-according-new-u-research
- https://iopscience.iop.org/article/10.3847/1538-3881/ae9089
JWST/MIRIが分子円盤風から原子円盤風への進化を明らかにする JWST/MIRI Reveals the Evolution from Molecular to Atomic Disk Winds
Naman S. Bajaj, Ilaria Pascucci, Sylvie Cabrit, Suzan Edwards, Gabriele Cugno, Andrew D. Sellek, Joan R. Najita, Ke Zhang, Richard Alexander, Gregory J. Herczeg,…
The Astronomical Journal Published: 2026 August 25
DOI:10.3847/1538-3881/ae9089
Abstract
The evolution and dispersal of protoplanetary disks—governed by accretion, magnetically launched jets and winds, and photoevaporative winds—fundamentally shape planetary systems. Determining how these mass-loss processes coevolve is crucial for constraining planet formation pathways. We analyze archival James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) integral field unit data of 72 inclined (i > 40°), mostly Class II disks to identify and characterize spatially resolved jets and winds, focusing on [Ne II] and H2 lines. Extended emission in H2 S(1), S(3), S(5), S(7), and/or [Ne II] is detected toward 66 disks, revealing diverse morphologies. We develop a framework to identify conical H2 winds and high-velocity [Ne II] jets perpendicular to the disk, detecting them toward 46 and 40 disks, respectively. All sources with [Ne II] jets exhibit a corresponding wind traced in either H2 (85%) or [O I], establishing a connection between jets and winds. The detection fractions of [Ne II] jets and H2 winds correlate positively with mass accretion rate, with no dependence on disk inclination or stellar mass. Conversely, marginally resolved low-velocity [Ne II] winds are found preferentially toward lower accretors. Among sources with H2 winds, detection of hotter winds traced by S(7) and S(5) declines more rapidly with decreasing accretion rate than that of the colder S(1) component. Comparison with high-resolution [O I] 6300Å spectroscopy reveals [O I] low-velocity components and extended H2 wind detections preferentially toward moderate-to-high accretors (≳10-8.5M・◎yr-1), whereas lower accretors exhibit only [O I] and [Ne II] winds. Together, these results indicate that atomic jets and atomic+molecular winds, consistent with an MHD disk-wind origin, dominate during early, actively accreting disk phases, while at lower accretion rates, jets weaken and winds become predominantly atomic.
