Article
Astronomy & Astrophysics
Nick Choksi, Eugene Chiang
Summary: This study investigates gaps in protoplanetary discs suspected to be opened by planets. By analyzing observational data and simulations, it is found that the accretion rates of planets within these gaps and in the PDS 70 disc are consistent with the system age, indicating they may be undergoing their final mass doublings. The study also predicts gas surface densities for gaps without data and suggests that the accretion rates of the PDS 70 planets are much higher than previously estimated.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
M. Fritscher, J. Teiser
Summary: The stability of planetesimals is crucial for their growth and evolution, and it depends on the stability, adhesion, and fragmentation of macroscopic agglomerates. In this study, we investigate the stability of highly porous CO2 agglomerates, which are abundant in the outer parts of protoplanetary discs. Our experiments show that the tensile strength of the agglomerates follows a power law dependence on the volume filling. The surface energy of the agglomerates is calculated to be γ = 0.060 +/- 0.022 J m(-2).
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Jessica Speedie, Ralph E. Pudritz, A. J. Cridland, Farzana Meru, Richard A. Booth
Summary: ALMA observations of protoplanetary discs have revealed dust ring/gap structures that can be explained by the presence of planets. Simulations show that in high viscosity discs, inward migration prevails and forms compact planetary systems, while in low viscosity discs, low mass planets can migrate outward before eventually migrating inward.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Lin Qiao, Gavin A. L. Coleman, Thomas J. Haworth
Summary: We demonstrate that planet formation via pebble accretion is sensitive to external photoevaporation of the outer disc. Pebble accretion relies on the supply of pebble flux from the outer disc, but if external photoevaporation truncates the disc too fast, it can limit the availability of pebble mass for planet growth. However, cloud shielding can protect the disc and preserve the pebble reservoir, resulting in significant differences in planetary properties.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Yinhao Wu, Clement Baruteau, Sergei Nayakshin
Summary: ALMA has observed over 200 annular structures in protoplanetary discs, indicating the possible presence of planets. Determining the mass of these hypothetical planets is challenging due to the degeneracy caused by disc physical properties. In this study, we argue against the assumption of a steady-state model by showing how the dynamics of the planet and dust can break the degeneracies. By conducting hydrodynamical simulations and dust radiative transfer calculations, we found that allowing the planet to migrate in the simulation leads to runaway migration and depletion of the disc dust.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Arturo Cevallos Soto, Jonathan C. Tan, Xiao Hu, Chia-Jung Hsu, Catherine Walsh
Summary: Inside-out planet formation theory suggests that certain types of planets are formed in situ near the inner boundary of protoplanetary discs. This study presents a model that predicts the physical and chemical evolution of these discs, showing that water-rich planets can form close to the star while the outer regions become dust-depleted. These findings provide important insights into the formation and composition of planets.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Yinhao Wu, Yi-Xian Chen, Haochang Jiang, Ruobing Dong, Enrique Macias, Min-Kai Lin, Giovanni P. Rosotti, Vardan Elbakyan
Summary: A novel approach to distinguishing wind-driven and turbulence-driven accretion has been proposed by studying the gap and ring morphology of planet-forming discs in ALMA continuum. Results from hydrodynamical simulations show that gap-opening planets in wind-driven accreting discs generate characteristic dust substructures that differ from those in purely viscous discs. The classification of planet-induced features sets up a potential method to constrain the strength of magnetized disc wind and viscosity based on observed morphology.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Matthew Alessi, Ralph E. Pudritz
Summary: Recent surveys have found that protoplanetary discs have lower levels of turbulence than expected, and magnetized disc winds may play a dominant role in angular momentum transport. This has important implications for the process of planet formation. By computing the physical and chemical evolution of discs and the formation and migration of planets, researchers have found that populations produced from discs with different levels of turbulence and winds strength fit better with observations, compared to populations with constant values. These models suggest a substantial population of super Earths at specific orbital radii, as well as distinct populations of hot Jupiter and warm Jupiter planets.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Maxwell X. Cai, Jonathan C. Tan, Simon Portegies Zwart
Summary: This study investigates the formation process of planetesimals in the theory of Inside-Out Planet Formation (IOPF) through collisional evolution simulations. The research finds that the planetesimal ring undergoes oligarchic evolution, resulting in 2 or 3 surviving oligarchs on nearly coplanar and circular orbits. However, a relatively massive secondary planet always remains, which is inconsistent with the observed properties of innermost planet pairs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
G. Andama, N. Ndugu, S. K. Anguma, E. Jurua
Summary: This study investigates the impact of globally perturbed discs on dust evolution and core growth through simulations, focusing on the formation of planetary cores at pressure minima and maxima. The results show that pressure maxima generated by planets or other physical phenomena can hinder planet formation in the inner parts of the disc, while multiple wave-like pressure bumps can promote rapid planet formation in broad areas of the disc.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
N. Ndugu, O. P. Abedigamba, G. Andama
Summary: This study investigates how protoplanetary discs in stellar clusters are affected by background heating, disc truncation, and photoevaporation, and how disc truncation impacts planet formation. The findings show that disc truncation reduces disc mass and decreases the occurrence rates of gas giant planets, with hot Jupiters being more frequent than cold Jupiters.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Haochang Jiang, Chris W. Ormel
Summary: ALMA observations have shown that dust rings in protoplanetary discs are important for planet formation, where planetesimals can grow efficiently via pebble accretion. Type-I planet migration is crucial for the evolution of rings and planets.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Francesco Bollati, Giuseppe Lodato, Daniel J. Price, Christophe Pinte
Summary: This paper presents a new technique for detecting protoplanets by observing the kinematics of surrounding gas. It shows that gravitational perturbations from a planet can produce unique 'kinks' in channel maps of different gas species, which can be reproduced using semi-analytic models. The study confirms the consistency of observed kinks with planet-induced wake and provides methods for quantifying planet mass from kink amplitude, as well as extending the theory to include damping effects for localized kinks.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Gavin A. L. Coleman
Summary: Planet formation models often skip the crucial step of planetesimal/proto-embryo formation. This study includes prescriptions for planetesimal and proto-embryo formation from trapped pebbles in pressure bumps, examining their sizes and distributions throughout the disc. Results show that planetesimal sizes increase with orbital distance and proto-embryo masses increase with orbital radius. By combining different accretion scenarios, more massive proto-embryos can form at larger distances, allowing for a better understanding of planetary system formation.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Jesper Nielsen, Matthew Raymond Gent, Maria Bergemann, Philipp Eitner, Anders Johansen
Summary: As the stellar compositions evolve in the Milky Way, the populations of planets formed will also change. By using a large stellar sample representing different chemical compositions and simulating planet formation around these stars, we found that the masses of synthetic planets increase with increasing stellar metallicity. Giant planets and super-Earths are most common around stars with low alpha-abundance, while they are rare around stars with high alpha-abundance or in the halo. Water-rich planets are less common around low-metallicity stars due to the inhibition of efficient growth beyond the water ice line. Our work demonstrates the influence of Galactic chemical evolution and stellar parameters on the resulting planet population.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Giovanni P. Rosotti, Richard Teague, Cornelis Dullemond, Richard A. Booth, Cathie J. Clarke
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
Jeff Jennings, Richard A. Booth, Marco Tazzari, Giovanni P. Rosotti, Cathie J. Clarke
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
Richard A. Booth, Cathie J. Clarke
Summary: In the process of dust removal in protoplanetary disc winds, the delivery of dust from the disc to the wind is a critical first step, which is mainly determined by the vertical gas flow induced by mass loss in the disc rather than turbulent diffusion. A simple relation is provided between the maximum size of particle that can be delivered to the wind and the local mass-loss rate, predicting typical sizes for extreme-ultraviolet- or X-ray-driven winds.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Brodie J. Norfolk, Sarah T. Maddison, Christophe Pinte, Nienke van der Marel, Richard A. Booth, Logan Francis, Jean-Francois Gonzalez, Francois Menard, Chris M. Wright, Gerrit van der Plas, Himanshi Garg
Summary: The origin of inner dust cavities in transition discs remains unclear, with differences expected based on the clearing mechanism. Observations with ATCA and ALMA show that the brightness distributions of 8.8mm and sub-mm dust grains in transition discs peak at the same radius, suggesting a common cavity size possibly induced by a dust trap.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Chiara E. Scardoni, Richard A. Booth, Cathie J. Clarke
Summary: This paper investigates whether overdensity formation via streaming instability is consistent with recent observations in the Lupus star-forming region using simulations and comparisons with data. The study finds that clump formation leads to a decrease in the optically thick fraction ff and that the spectral index alpha may increase or decrease after the action of streaming instability. This behavior is observed to drive simulations towards the region where the data are located, especially when the instability is operative over a region of the disc that contributes significantly to the total mm flux.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Andrew D. Sellek, Cathie J. Clarke, Richard A. Booth
Summary: Thermal disc winds are important for the evolution and dispersal of protoplanetary discs. By generalizing previous models to include launch from an elevated base and non-isothermal conditions, and validating them with hydrodynamic simulations, this study found that wind launch depends on the Mach number and spatial domain filling. Elevation of the wind base has the strongest impact on launch velocity and flow morphology, while temperature gradients have minor effects.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Jessica Speedie, Ralph E. Pudritz, A. J. Cridland, Farzana Meru, Richard A. Booth
Summary: ALMA observations of protoplanetary discs have revealed dust ring/gap structures that can be explained by the presence of planets. Simulations show that in high viscosity discs, inward migration prevails and forms compact planetary systems, while in low viscosity discs, low mass planets can migrate outward before eventually migrating inward.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Jessica Speedie, Richard A. Booth, Ruobing Dong
Summary: ALMA continuum observations have revealed substructures in protoplanetary disks that may indicate the presence of embedded planets, but detecting planet-driven spiral arms has been challenging. This study tests the capabilities of ALMA to detect these spiral signals and shows that with the current design specification, ALMA is capable of detecting thermal mass planets that drive spirals. The study also highlights the importance of dust temperature in determining the detectability of spirals and suggests that gaps and rings can affect the recognition of colocated spirals.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Chiara E. Scardoni, Cathie J. Clarke, Giovanni P. Rosotti, Richard A. Booth, Richard D. Alexander, Enrico Ragusa
Summary: Recent studies have shown that in the planet-dominated regime, the torques acting on planets are correlated with the depth of the gap carved by the planet in the disc. Live-planet simulations demonstrate that the excitation of planet eccentricity can break the direct dependence between migration rate and torques, an effect not captured by fixed-planet simulations. Furthermore, a torque reversal at a certain critical value of the gap depth parameter K may shape the planetary system architecture and impede the formation of hot Jupiters through Type II migration.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Daniel P. Cummins, James E. Owen, Richard A. Booth
Summary: This study investigates the growth of a planetary embryo in a massive dust trap and finds that the thermal feedback from the accretion of pebbles leads to the formation of a vortex. The vortex allows for a rapid accretion rate, resulting in a planet with a significant amount of solids. The authors speculate that this extreme formation scenario may explain the origin of giant planets enriched in heavy elements.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Jeff Jennings, Marco Tazzari, Cathie J. Clarke, Richard A. Booth, Giovanni P. Rosotti
Summary: Annular gaps and rings are common in protoplanetary discs in the Taurus molecular cloud. New substructures were identified using the non-parametric model Frankenstein, revealing trends and features such as a higher occurrence rate of substructure in compact discs, underresolved substructure in the innermost disc of extended sources, and a common shoulder morphology in ring structures.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Richard A. Booth, James E. Owen, Matthaus Schulik
Summary: Ultrashort period planets provide insights into exoplanets' interior through observing the material evaporated from their rocky interiors. Disintegrating planets with dusty tails, believed to originate from dust condensation in thermally driven winds, have highly variable nature. New radiation-hydrodynamic simulations show that dust forms readily in the winds and the coupling of temperature and dust's opacity can drive time-variable flows. These dusty tails are a signature of catastrophically evaporating planets close to the end of their lives.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Madelyn Broome, Mihkel Kama, Richard Booth, Oliver Shorttle
Summary: The composition of forming planets is determined by the thermal structure of the protoplanetary disc, which is influenced by dust radiative transfer, accretional heating, and the occurrence of gaps. This study uses a radiative transfer code to model the thermal structure of 2D dust with gaps corresponding to different planetary masses and orbital radii. The results show that gaps can significantly affect the temperature distribution within the disc, leading to variations in dust-gas segregation and the position of icelines.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Matthaus Schulik, Richard A. Booth
Summary: We present a new 1D multiphysics simulation code for hydrodynamic escape problems and planetary accretion models. The code treats multiple species as separate hydrodynamic fields, couples them via friction laws, and allows for multiband flux-limited radiation transport. The code demonstrates correct physical behavior and offers new applications for exploring advanced planetary evolution schemes.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
James M. Miley, Olja Panic, Richard A. Booth, John D. Ilee, Shigeru Ida, Masanobu Kunitomo
Summary: This study investigates the impact of pre-main sequence stellar luminosity evolution on the thermal and chemical properties of disc mid-planes. It reveals that temperature profiles diverge significantly for different stellar masses beyond 2 Myr, affecting the location of the CO snowline. The research indicates a well-defined stellar mass and age range for the formation of high C/O gas giants.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)