How cooling influences circumbinary discs

Abstract

Circumbinary disc observations and simulations show large, eccentric inner cavities. Recent work has shown that the shape and size of these cavities depend on the aspect ratio and viscosity of the disc, as well as the binary eccentricity and mass ratio. It has been further shown that, for gaps created by planets, the cooling timescale significantly affects the shape and size of the gap. In this study, we consider the effect of different cooling models on the cavity shape in a circumbinary disc. We compare locally isothermal and radiatively cooled disc models to ones with a parametrised cooling timescale ($\beta$-cooling), implemented in 2D numerical simulations for varying binary eccentricities. While the shape of the cavity for radiative and locally isothermal models remains comparable, the inner disc structure changes slightly, leading to a change in the precession rate of the disc. With $\beta$-cooled models, the shape and size of the cavity changes dramatically towards values of $\beta$=1. Based on our findings, we introduce a parametrised $\beta$ model that accounts for the shorter cooling timescale inside the cavity while adequately reproducing the results of the radiative model, and we highlight that accurate treatment of the thermodynamics inside the cavity has a significant impact in modelling circumbinary systems.

12 pages, 11 figures, 1 table; accepted for publication in A&A

References in corpus (23)

• PLUTO: a Numerical Code for Computational Astrophysics
• The Transiting Circumbinary Planets Kepler-34 and Kepler-35
• Hydrodynamic Torques in Circumbinary Accretion Disks
• Circumbinary Accretion from Finite and Infinite Disks
• Gas-driven inspiral of binaries in thin accretion disks
• Orbital Evolution of Equal-mass Eccentric Binaries due to a Gas Disk: Eccentric Inspirals and Circular Outspirals
• TOI-1338: TESS' First Transiting Circumbinary Planet
• Discovery of a Third Transiting Planet in the Kepler-47 Circumbinary System
• The evolution of large cavities and disc eccentricity in circumbinary discs
• A Survey of Disc Thickness and Viscosity in Circumbinary Accretion: Binary Evolution, Variability, and Disc Morphology
• Preventing Anomalous Torques in Circumbinary Accretion Simulations
• The effects of disk self-gravity and radiative cooling on the formation of gaps and spirals by young planets
• Long-Lived Eccentric Modes in Circumbinary Disks
• Kepler-1661 b: A Neptune-sized Kepler Transiting Circumbinary Planet around a Grazing Eclipsing Binary
• Gaps and Rings in Protoplanetary Disks with Realistic Thermodynamics: The Critical Role of In-Plane Radiation Transport
• Parking planets in circumbinary discs
• Hydrodynamical turbulence in eccentric circumbinary discs and its impact on the in situ formation of circumbinary planets
• The Role of Disc Self-Gravity in Circumbinary Planet Systems: I. Disc Structure and Evolution
• How Binaries Accrete: Hydrodynamic Simulations with Passive Tracer Particles
• Binary orbital evolution driven by a circumbinary disc
• Circumbinary discs with radiative cooling and embedded planets
• Survival of planet-induced vortices in 2D disks
• Vertical settling of pebbles in turbulent circumbinary discs and the in situ formation of circumbinary planets

Cited by in corpus (2)

• On the Role of Gas Cooling in the Dynamics of Circumbinary Disks
• Three-dimensional evolution of radiative circumbinary discs: the size and shape of the inner cavity