English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

PDS 70 hosts two massive, still-accreting planets and the inclinedorientation of its protoplanetary disk presents a unique opportunity todirectly probe the vertical gas structure of a planet-hosting disk. Here, weuse high-spatial-resolution (${\approx}$0."1;10 au) observations in a set of COisotopologue lines and HCO$^+$ J=4-3 to map the full 2D $(r,z)$ disk structurefrom the disk atmosphere, as traced by $^{12}$CO, to closer to the midplane, asprobed by less abundant isotopologues and HCO$^+$. In the PDS 70 disk,$^{12}$CO traces a height of $z/r\approx0.3$, $^{13}$CO is found at$z/r\approx0.1$, and C$^{18}$O originates at, or near, the midplane. TheHCO$^+$ surface arises from $z/r\approx0.2$ and is one of the few non-COemission surfaces constrained with high fidelity in disks to date. In the$^{12}$CO J=3-2 line, we resolve a vertical dip and steep rise in height at thecavity wall, making PDS 70 the first transition disk where this effect isdirectly seen in line emitting heights. In the outer disk, the CO emissionheights of PDS 70 appear typical for its stellar mass and disk size and are notsubstantially altered by the two inner embedded planets. By combining COisotopologue and HCO$^+$ lines, we derive the 2D gas temperature structure andestimate a midplane CO snowline of ${\approx}$56-85 au. This implies that bothPDS 70b and 70c are located interior to the CO snowline and are likelyaccreting gas with a high C/O ratio of ${\approx}$1.0, which provides contextfor future planetary atmospheric measurements from, e.g., JWST, and forproperly modeling their formation histories.

Mapping the Vertical Gas Structure of the Planet-hosting PDS 70 Disk