Iceline Variations Driven by Protoplanetary Disc Gaps

Abstract

The composition of forming planets is strongly affected by the protoplanetary disc's thermal structure. This thermal structure is predominantly set by dust radiative transfer and viscous (accretional) heating and can be impacted by gaps - regions of low dust and gas density that can occur when planets form. The effect of variations in dust surface density on disc temperature has been poorly understood until now. In this work, we use the radiative transfer code MCMax to model the 2D dust thermal structure with individual gaps corresponding to planets with masses of 0.1 M${}_J$ - 5 M${}_J$ and orbital radii of 3, 5, and 10 AU. Low dust opacity in the gap allows radiation to penetrate deeper into the disc and warm the midplane by up to 16 K, but only for gaps located in the region of the disc where stellar irradiation is the dominant source of heat (here, a$\gtrsim$4 AU). In viscously-heated regions (a$\lesssim$4 AU), the midplane of the gap is relatively cooler by up to 100 K. Outside of the gap, broad radial oscillations in heating and cooling are present due to changes in disc flaring. These thermal features affect local segregation of volatile elements (H${}_2$O, CH${}_4$, CO2, CO) between the dust and gas. We find that icelines experience dramatic shifts relative to gapless models: up to 6.5 AU towards the star and 4.3 AU towards the midplane. While quantitative predictions of iceline deviations will require more sophisticated models which include transport and sublimation/condensation kinetics, our results provide evidence that planet-induced iceline variations represent a potential feedback from the planet onto the composition of material it is accreting.

11 pages, 5 figures. Accepted to MNRAS, published 20 April 2023

References in corpus (16)

• Coagulation, fragmentation and radial motion of solid particles in protoplanetary disks
• Analytical protostellar disk models 1: the effect of internal dissipation and surface irradiation on the structure of disks and the location of the snow line around Sun-like stars
• Radiative transfer in very optically thick circumstellar disks
• Mass Estimates of a Giant Planet in a Protoplanetary Disk from the Gap Structures
• Crystalline silicates and dust processing in the protoplanetary disks of the Taurus young cluster
• An opening criterion for dust gaps in protoplanetary discs
• On the gap-opening criterion of migrating planets in protoplanetary disks
• Protoplanetary Disks as (Possibly) Viscous Disks
• Molecules with ALMA at Planet-forming Scales (MAPS). VII. Sub-stellar O/H and C/H and super-stellar C/O in planet feeding gas
• From stellar nebula to planetesimals
• The effect of a planet on the dust distribution in a 3D protoplanetary disk
• Midplane temperature and outer edge of the protoplanetary disk around HD 163296
• Thermal Waves in Irradiated Protoplanetary Disks
• If you like C/O variations, you should have put a ring on it
• Effects of disc midplane evolution on CO snowline location
• Dust trapping in protoplanetary disks

Cited by in corpus (2)

• Chemical footprints of giant planet formation. Role of planet accretion in shaping the C/O ratio of protoplanetary disks
• Tracking the Chemical Evolution of Hydrocarbons Through Carbon Grain Supply in Protoplanetary Disks