ORCID Profile
0000-0002-3768-7542
Current Organisation
New Mexico State University
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Publisher: EDP Sciences
Date: 16-01-2015
Publisher: American Astronomical Society
Date: 16-03-2015
Publisher: American Astronomical Society
Date: 14-07-2020
Publisher: Cambridge University Press (CUP)
Date: 2016
DOI: 10.1017/PASA.2016.45
Abstract: The Protoplanetary Discussions conference—held in Edinburgh, UK, from 2016 March 7th–11th—included several open sessions led by participants. This paper reports on the discussions collectively concerned with the multi-physics modelling of protoplanetary discs, including the self-consistent calculation of gas and dust dynamics, radiative transfer, and chemistry. After a short introduction to each of these disciplines in isolation, we identify a series of burning questions and grand challenges associated with their continuing development and integration. We then discuss potential pathways towards solving these challenges, grouped by strategical, technical, and collaborative developments. This paper is not intended to be a review, but rather to motivate and direct future research and collaboration across typically distinct fields based on community-driven input , to encourage further progress in our understanding of circumstellar and protoplanetary discs.
Publisher: American Astronomical Society
Date: 06-2022
Abstract: The elemental ratios of carbon, nitrogen, and oxygen in the atmospheres of hot Jupiters may hold clues to their formation locations in the protostellar disk. In this work, we adopt gas-phase chemical abundances of C, N, and O from several locations in a disk chemical kinetics model as sources for the envelope of the hot Jupiter HD 209458b and evolve the atmospheric composition of the planet using a 1D chemical kinetics model, treating both vertical mixing and photochemistry. We consider two atmospheric pressure-temperature profiles, one with and one without a thermal inversion. From each of the resulting 32 atmospheric composition profiles, we find that the molecules CH 4 , NH 3 , HCN, and C 2 H 2 are more prominent in the atmospheres computed using a realistic noninverted P – T profile in comparison to a prior equilibrium chemistry based work, which used an analytical P – T profile. We also compute the synthetic transmission and emission spectra for these atmospheres and find that many spectral features vary with the location in the disk where the planetary envelope was accreted. By comparing with the species detected using the latest high-resolution ground-based observations, our model suggests that HD 209458b could have accreted most of its gas between the CO 2 and CH 4 ice lines with a supersolar C/O ratio from its protostellar disk, which in turn directly inherited its chemical abundances from the protostellar cloud. Finally, we simulate observing the planet with the James Webb Space Telescope (JWST) and show that differences in spectral signatures of key species can be recognized. Our study demonstrates the enormous importance of JWST in providing new insights into hot-Jupiter formation environments.
Publisher: American Astronomical Society
Date: 31-07-2023
Publisher: Oxford University Press (OUP)
Date: 19-03-2019
DOI: 10.1093/MNRAS/STZ802
Publisher: American Astronomical Society
Date: 29-10-2015
Publisher: Oxford University Press (OUP)
Date: 30-11-2018
Publisher: American Astronomical Society
Date: 10-11-2017
Publisher: American Astronomical Society
Date: 27-11-2017
Publisher: American Astronomical Society
Date: 07-2023
Abstract: We investigate planetary migration in the dead zone of a protoplanetary disk where there is a set of spiral waves propagating inward due to the turbulence in the active zone and the Rossby wave instability, which occurs at the transition between the dead and active zones. We perform global 3D unstratified magnetohydrodynamical simulations of a gaseous disk with the FARGO3D code, using weak gradients in the static resistivity profiles that trigger the formation of a vortex at the outer edge of the dead zone. We find that once the Rossby vortex develops, spiral waves in the dead zone emerge and interact with embedded, migrating planets by wave interference, which notably changes their migration. The inward migration becomes faster depending on the mass of the planet, due mostly to the constructive (destructive) interference between the outer (inner) spiral arm of the planet and the destruction of the dynamics of the horseshoe region by means of the set of background spiral waves propagating inward. The constructive wave interference produces a more negative Lindblad differential torque, which inevitably leads to an inward migration. Lastly, for massive planets embedded in the dead zone, we find that the spiral waves can create an asymmetric, wider, and deeper gap than in the case of α -disks and can prevent the formation of vortices at the outer edge of the gap. The latter could generate a faster or slower migration compared to the standard type-II migration.
Location: United States of America
Location: United States of America
No related grants have been discovered for Wladimir Lyra.