UV processing of icy pebbles in the outer parts of VSI-turbulent disks
(2025) In Astronomy and Astrophysics 693.- Abstract
Icy dust particles emerge in star-forming clouds and are subsequently incorporated in protoplanetary disks, where they coagulate into larger pebbles up to millimeter in size. In the disk midplane, ices are shielded from UV radiation, but moderate levels of disk turbulence can lift small particles to the disk surface, where they can be altered, or destroyed. Nevertheless, studies of comets and meteorites generally find that ices at least partly retain their interstellar medium (ISM) composition before being accreted onto these minor bodies. We modeled this process through hydrodynamical simulations with vertical shear instability (VSI) driven turbulence in the outer protoplanetary disk. We used the PLUTO code in a 2.5 D global accretion... (More)
Icy dust particles emerge in star-forming clouds and are subsequently incorporated in protoplanetary disks, where they coagulate into larger pebbles up to millimeter in size. In the disk midplane, ices are shielded from UV radiation, but moderate levels of disk turbulence can lift small particles to the disk surface, where they can be altered, or destroyed. Nevertheless, studies of comets and meteorites generally find that ices at least partly retain their interstellar medium (ISM) composition before being accreted onto these minor bodies. We modeled this process through hydrodynamical simulations with vertical shear instability (VSI) driven turbulence in the outer protoplanetary disk. We used the PLUTO code in a 2.5 D global accretion setup and included Lagrangian dust particles of 0.1 and 1 mm sizes. In a post-processing step, we used the RADMC3D code to generate the local UV radiation field to assess the level of ice processing of pebbles. We find that a small fraction (∼17%) of 100 μm size particles are frequently lifted up to Z/R = 0.2, which can result in the loss of their pristine composition as their residence time in this layer allow effective CO and water photodissociation. The larger 1 mm size particles remain UV-shielded in the disk midplane throughout the dynamical evolution of the disk. Our results indicate that the assembly of icy bodies via the accretion of drifting millimeter-sized icy pebbles can explain the presence of pristine ice from the ISM, even in VSI-turbulent disks. Nevertheless, particles ≤100 μm experience efficient UV processing and may mix with unaltered icy pebbles, resulting in a less ISM-like composition in the midplane.
(Less)
- author
- Flores-Rivera, Lizxandra ; Lambrechts, Michiel LU ; Gavino, Sacha ; Lorek, Sebastian LU ; Flock, Mario ; Johansen, Anders LU and Mignone, Andrea
- publishing date
- 2025-01-01
- type
- Contribution to journal
- publication status
- published
- keywords
- Protoplanetary disks
- in
- Astronomy and Astrophysics
- volume
- 693
- article number
- A281
- publisher
- EDP Sciences
- external identifiers
-
- scopus:85216323048
- ISSN
- 0004-6361
- DOI
- 10.1051/0004-6361/202452933
- language
- English
- LU publication?
- no
- additional info
- Publisher Copyright: © 2025 The Authors.
- id
- a315bfb8-74de-494b-8369-89966ea77f1a
- date added to LUP
- 2025-05-12 11:51:42
- date last changed
- 2025-05-13 11:47:42
@article{a315bfb8-74de-494b-8369-89966ea77f1a,
abstract = {{<p>Icy dust particles emerge in star-forming clouds and are subsequently incorporated in protoplanetary disks, where they coagulate into larger pebbles up to millimeter in size. In the disk midplane, ices are shielded from UV radiation, but moderate levels of disk turbulence can lift small particles to the disk surface, where they can be altered, or destroyed. Nevertheless, studies of comets and meteorites generally find that ices at least partly retain their interstellar medium (ISM) composition before being accreted onto these minor bodies. We modeled this process through hydrodynamical simulations with vertical shear instability (VSI) driven turbulence in the outer protoplanetary disk. We used the PLUTO code in a 2.5 D global accretion setup and included Lagrangian dust particles of 0.1 and 1 mm sizes. In a post-processing step, we used the RADMC3D code to generate the local UV radiation field to assess the level of ice processing of pebbles. We find that a small fraction (∼17%) of 100 μm size particles are frequently lifted up to Z/R = 0.2, which can result in the loss of their pristine composition as their residence time in this layer allow effective CO and water photodissociation. The larger 1 mm size particles remain UV-shielded in the disk midplane throughout the dynamical evolution of the disk. Our results indicate that the assembly of icy bodies via the accretion of drifting millimeter-sized icy pebbles can explain the presence of pristine ice from the ISM, even in VSI-turbulent disks. Nevertheless, particles ≤100 μm experience efficient UV processing and may mix with unaltered icy pebbles, resulting in a less ISM-like composition in the midplane.</p>}},
author = {{Flores-Rivera, Lizxandra and Lambrechts, Michiel and Gavino, Sacha and Lorek, Sebastian and Flock, Mario and Johansen, Anders and Mignone, Andrea}},
issn = {{0004-6361}},
keywords = {{Protoplanetary disks}},
language = {{eng}},
month = {{01}},
publisher = {{EDP Sciences}},
series = {{Astronomy and Astrophysics}},
title = {{UV processing of icy pebbles in the outer parts of VSI-turbulent disks}},
url = {{http://dx.doi.org/10.1051/0004-6361/202452933}},
doi = {{10.1051/0004-6361/202452933}},
volume = {{693}},
year = {{2025}},
}