Impact of embedded circumplanetary winds on the circumstellar disk: I. Reshaping the local accretion environment

TL;DR

This study evaluates how embedded planet–driven winds reshape the local circumstellar environment. Using 3D hydrodynamic simulations with a parametric wind term, the authors find that while the global protoplanetary disk remains largely unaffected, the wind significantly reorganizes gas on planetary scales, redirecting accretion from polar to equatorial regions and reducing the reservoir within the Hill sphere, potentially slowing planetary growth. Accretion-enabled runs show winds generally suppress total accretion, with stronger winds producing larger depletion, though weak winds can occasionally maintain or slightly enhance midplane accretion depending on accretion efficiency. The work emphasizes wind-driven mass depletion as a plausible mechanism to regulate giant planet growth and motivates future studies linking wind launching physics (magnetic or thermal) to the observed CPD dynamics, including inclined or time-variable outflows.

Abstract

The existence of winds is among the uncertainties related to the growth of giant planets. Such circumplanetary outflows have been proposed to explain kinematic and chemical structures in protoplanetary disks. We investigate the immediate impact of circumplanetary outflows on the circumstellar disk environment, the planetary vicinity, and planetary growth. We performed three-dimensional hydrodynamic simulations using \texttt{FARGO3D}, implementing a parametric wind launched from the vicinity of an embedded planet. Although the imposed configurations for the outflows do not significantly alter the global structure of the disk, they do substantially redistribute material in the vicinity of the embedded planet. In particular, the wind redirects accretion flows from polar to equatorial latitudes, resulting in variable accretion patterns over time. Although the mass accretion rate variations depend on the efficiency of the outflows, their presence diminishes the accretion rate over time and the total mass reservoir within the Hill sphere and the planet's direct vicinity, potentially slowing or limiting planetary growth.

Figures (17)

• Figure 1: Visual representation of Equation \ref{['eq:GammaDef']}, showing the ratio $\vec{\Gamma}(r, \theta)/A_{\gamma}$ for two smoothing lengths, $r_s = 0.5r_H$ (top row) and $r_s = 0.8r_H$ (bottom row), and three steepness parameters, $n = 4$, $8$, and $16$ (left to right). Colored contours correspond to values of $0.8$, $0.6$, $0.4$, $0.3$, $0.2$, $0.1$, and $0.05$. The Hill radius $r_H$ sets the radial scale, with the planet positioned at the center of each panel.
• Figure 2: Local kinematic perturbation fraction, $f$, as a function of distance from the planet in units of local scale height. Each curve represents a different wind strength parameter, $A_{\gamma}$, calculated using Equation \ref{['eq:f_from_Agamma']}. The simulation cases for $A_{\gamma} = 4$ and $A_{\gamma} = 8$ are highlighted in green and red, respectively.
• Figure 3: Estimated mass-loss rate $\dot{M}_w$ as a function of distance from the planet (in units of local scale height) for different $A_{\gamma}$ values. The estimate assumes a volumetric density derived from a midplane surface density of $\Sigma_0 = 40\,\mathrm{g\,cm^{-2}}$ at $R_0=10\,\mathrm{AU}$.
• Figure 4: Comparative snapshots of simulations $\Gamma_0$, $\Gamma_2$, $\Gamma_4$, and $\Gamma_8$ (from top to bottom), all taken at 500 planetary orbits. The left column shows the logarithmic gas density in the disk midplane ($R$-$\phi$), with a zoomed-in view centered on the planet; both panels share the same color scale. The right column presents meridional slices ($R$-$Z$) of the logarithmic gas density. The full disk view and the zoomed-in region use different color scales, with the latter denoted by $\rho_{\mathrm{zoom}}$, to highlight both global and local density structures.
• Figure 5: Surface density profile evolution for $\Gamma_0$ (top-left), $\Gamma_2$ (top-right), $\Gamma_4$ (bottom-left), and $\Gamma_8$ (bottom-right). The planet's position at 10 au is marked by a red dashed line. The planet opens a primary gap and excites three overdensities ($D_1, D_2, D_3$). Surface density profiles are obtained by integrating the volumetric density over the polar angle ($\theta$) and then averaging over the azimuthal angle ($\phi$) for each orbit.