Planetesimal formation starts at the snow line

Drążkowska, J.; Alibert, Yann (2017). Planetesimal formation starts at the snow line. Astronomy and astrophysics, 608(A92), A92. EDP Sciences 10.1051/0004-6361/201731491

[img] Text
aa31491-17.pdf - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (727kB) | Request a copy

Context. The formation stage of planetesimals represents a major gap in our understanding of the planet formation process. Late-stage planet accretion models typically make arbitrary assumptions about planetesimal and pebble distribution, while dust evolution models predict that planetesimal formation is only possible at some orbital distances. Aims. We wish to test the importance of the water snow line in triggering the formation of the first planetesimals during the gas-rich phase of a protoplanetary disk, when cores of giant planets have to form. Methods. We connected prescriptions for gas disk evolution, dust growth and fragmentation, water ice evaporation and recondensation, the transport of both solids and water vapor, and planetesimal formation via streaming instability into a single one-dimensional model for protoplanetary disk evolution. Results. We find that processes taking place around the snow line facilitate planetesimal formation in two ways. First, because the sticking properties between wet and dry aggregates change, a “traffic jam” inside of the snow line slows the fall of solids onto the star. Second, ice evaporation and outward diffusion of water followed by its recondensation increases the abundance of icy pebbles that trigger planetesimal formation via streaming instability just outside of the snow line. Conclusions. Planetesimal formation is hindered by growth barriers and radial drift and thus requires particular conditions to take place. The snow line is a favorable location where planetesimal formation is possible for a wide range of conditions, but not in every protoplanetary disk model, however. This process is particularly promoted in large cool disks with low intrinsic turbulence and an increased initial dust-to-gas ratio.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Physics Institute > Space Research and Planetary Sciences
08 Faculty of Science > Physics Institute > Space Research and Planetary Sciences > Theoretical Astrophysics and Planetary Science (TAPS)
08 Faculty of Science > Physics Institute
08 Faculty of Science > Physics Institute > NCCR PlanetS

UniBE Contributor:

Alibert, Yann

Subjects:

500 Science > 520 Astronomy
600 Technology > 620 Engineering

ISSN:

0004-6361

Publisher:

EDP Sciences

Language:

English

Submitter:

Yann Alibert

Date Deposited:

17 Apr 2018 17:37

Last Modified:

22 Apr 2018 02:19

Publisher DOI:

10.1051/0004-6361/201731491

Uncontrolled Keywords:

accretion, accretion disks, circumstellar matter, protoplanetary disks, planets and satellites: formation, methods: numerical

BORIS DOI:

10.7892/boris.109873

URI:

https://boris.unibe.ch/id/eprint/109873

Actions (login required)

Edit item Edit item
Provide Feedback