Article
Astronomy & Astrophysics
Ryuki Hyodo, Tristan Guillot, Shigeru Ida, Satoshi Okuzumi, Andrew N. Youdin
Summary: This study investigates the local pile-up of silicate dust and pebbles around the snow line, providing insights into the disk conditions for solid accumulation inside and outside the snow line with different parameters.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
N. Oberg, I. Kamp, S. Cazaux, P. Woitke, W. F. Thi
Summary: This study aims to explore the process of ice formation in circumplanetary disks (CPDs) and constrain the properties of the disk that are consistent with the formation of icy moon systems. The results show that ice can form efficiently in CPDs, and three-body reactions play an important role in water formation. The dust in the CPD midplane needs to be depleted by a factor of 10-50 compared to the circumstellar disk to produce solids with the desired ice to rock ratio of the Galilean satellites. The snowline of the CPD is not affected by radial grain drift, indicating a primordial compositional gradient in the Galilean satellites.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
P. Pinilla, N. T. Kurtovic, M. Benisty, C. F. Manara, A. Natta, E. Sanchis, M. Tazzari, S. M. Stammler, L. Ricci, L. Testi
Summary: The frequency of Earth-sized planets in habitable zones appears to be higher around M-dwarfs, making these systems exciting laboratories to investigate planet formation. Observations of protoplanetary disks around very low-mass stars and brown dwarfs remain challenging and little is known about their properties. The characteristics of the disk around CIDA 1 challenge current dust evolution models, particularly processes like fragmentation, growth, and diffusion of particles inside pressure bumps.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Yueh-Ning Lee, Sebastien Charnoz, Patrick Hennebelle
Summary: Efforts to understand the connection between collapsing prestellar cores and developed disks have been limited in the research communities studying star formation and protoplanetary disk evolution. Simple models of pure hydrodynamics and angular momentum conservation are still widely used, despite the recognition of the importance of magnetic fields in stellar formation. This study revisited the assemblage phase of protoplanetary disks, incorporating current knowledge of prestellar core collapse and employing 3D magnetohydrodynamic simulations with ambipolar diffusion and full radiative transfer.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
J. Mueller-Horn, G. Pichierri, B. Bitsch
Summary: This study investigates the possibility of the gap-opening planets in the disk around HD 163296 serving as progenitors of the exoplanet population detected around A-type stars. The results show that the final configuration of the planets is largely determined by the viscosity parameter of the disk and less dependent on the disk lifetime and initial planetary parameters.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Paola Pinilla, Antonio Garufi, Matias Garate
Summary: The frequency of giant planets may decrease for intermediate-mass stars, and the mechanism behind this phenomenon remains unclear. Through theoretical analysis, it is found that the radial drift velocity of dust particles sharply increases after 1-2 million years around intermediate-mass stars, potentially hindering planet formation. This high radial drift could explain the lack of disk detections around older intermediate-mass stars. Future high-resolution images can help us understand why planets around intermediate-mass stars are rare.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Masanobu Kunitomo, Shigeru Ida, Taku Takeuchi, Olja Panic, James M. Miley, Takeru K. Suzuki
Summary: The study reveals that the far-ultraviolet, extreme-ultraviolet, and X-ray luminosities of intermediate-mass stars undergo orders of magnitude changes within a few million years, leading to significant evolution in the photoevaporation rate. Therefore, it is concluded that stellar evolution plays a crucial role in the evolution of protoplanetary disks around intermediate-mass stars.
ASTROPHYSICAL JOURNAL
(2021)
Article
Physics, Particles & Fields
Tong-Yu He, Ziqiang Cai, Rong-Jia Yang
Summary: We investigate the accretion process in the thin disk around a supermassive black hole within the context of Einstein-aether-scalar theory. Our results demonstrate that the physical properties of the disk, including energy flux, radiation temperature, spectra cut-off frequency, spectra luminosity, and conversion efficiency, all decrease with increasing parameter value. Furthermore, we find that certain parameter values allowed by the theory are incompatible with the observed physical properties of the disk.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
Chunhua Zhu, Helei Liu, Zhaojun Wang, Guoliang Lu
Summary: This study investigated the formation of DB WDs and the effects of input parameters on the structures of these WDs. It discussed the impacts of various factors on the element abundances of WD surfaces and compared theoretical models with observations to understand the evolutionary sequence of heavy element abundance on DBZ WD surfaces. Results showed that input parameters had minimal effects on DB WD structures, while mass-accretion rate and effective temperature were key determinants of heavy element abundances on WD surfaces.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Tommy Chi Ho Lau, Joanna Drazkowska, Sebastian M. Stammler, Tilman Birnstiel, Cornelis P. Dullemond
Summary: Research has found that pressure bumps in protoplanetary disks provide favorable locations for the emergence and rapid growth of planetary cores through pebble accretion, due to increased dust density, grain size, and reduced pebble accretion onset mass.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
O. Sokoliuk, S. Praharaj, A. Baransky, P. K. Sahoo
Summary: This paper investigates various spherically symmetric wormhole solutions under the influence of tidal forces, and applies multiple methods for detection. Theoretical predictions are made on test particle orbital motion and ray-tracing images are obtained to analyze the results. The approximate radius of the wormhole shadow is also calculated using microlensing techniques.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Yayaati Chachan, Eve J. Lee
Summary: Current measurements of planet population show three seemingly contradictory signatures: close-in super-Earths are more prevalent around M dwarfs than FGK dwarfs; inner super-Earths are correlated with outer giants; and outer giants are less common around M dwarfs than FGK dwarfs. A simple framework combining pebble accretion theory with measurements of dust masses in protoplanetary disks can reconcile all three observations. Cooler stars are more efficient at converting pebbles into planetary cores at short orbital periods, while hotter stars are more likely to harbor more massive dust disks, leading to higher giant planet occurrence rates.
ASTROPHYSICAL JOURNAL LETTERS
(2023)
Article
Astronomy & Astrophysics
Philipp Weber, Sebastian Perez, Alice Zurlo, James Miley, Antonio Hales, Lucas Cieza, David Principe, Miguel Carcamo, Antonio Garufi, Agnes Kospal, Michihiro Takami, Joel Kastner, Zhaohuan Zhu, Jonathan Williams
Summary: The formation of giant planets has been traditionally divided into two pathways: core accretion and gravitational instability. Recent observations have made gravitational instability less favored, but a new study presents evidence of this process occurring on planetary scales. By analyzing polarized light observations and 1.3 mm data of the young outbursting object V960 Mon, researchers discovered clumps of continuum emission aligned along a spiral arm, suggesting the presence of fragmented material formed through gravitational collapse. This finding provides insight into planet formation and its connection with the outbursting state of V960 Mon.
ASTROPHYSICAL JOURNAL LETTERS
(2023)
Article
Astronomy & Astrophysics
F. H. Vincent, S. E. Gralla, A. Lupsasca, M. Wielgus
Summary: This study aims to explore various accretion flows onto supermassive black hole M 87* by developing an analytical model and numerically integrating the radiative transfer equation in Kerr spacetime. The results show that the n = 2 photon ring at 345 GHz displays clear signatures in both the image and visibility domains, indicating promising future space-VLBI measurements.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
N. T. Kurtovic, P. Pinilla, F. Long, M. Benisty, C. F. Manara, A. Natta, I Pascucci, L. Ricci, A. Scholz, L. Testi
Summary: The discovery of giant planets orbiting very low mass stars (VLMS) and observed substructures in disks around VLMS challenge existing planet formation models. Observations show the presence of cavities, rings, and gaps in disks around VLMS, providing insights into radial drift. Additionally, the comparison of gas and dust emission in these disks reveals valuable information about radial extent and structural formation.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
I. N. Ziglina, A. B. Makalkin
SOLAR SYSTEM RESEARCH
(2016)
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Astronomy & Astrophysics
A. B. Makalkin, M. E. Artyushkova
SOLAR SYSTEM RESEARCH
(2017)
Article
Astronomy & Astrophysics
Vladimir V. Busarev, Andrei B. Makalkin, Faith Vilas, Sergey I. Barabanov, Marina P. Scherbina
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Astronomy & Astrophysics
A. B. Makalkin, V. A. Dorofeeva
SOLAR SYSTEM RESEARCH
(2009)
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Astronomy & Astrophysics
A. B. Makalkin, I. N. Ziglina
SOLAR SYSTEM RESEARCH
(2018)
Article
Geochemistry & Geophysics
A. B. Makalkin, I. N. Ziglina, M. E. Artyushkova
IZVESTIYA-PHYSICS OF THE SOLID EARTH
(2019)
Article
Astronomy & Astrophysics
A. B. Makalkin, V. A. Dorofeeva
SOLAR SYSTEM RESEARCH
(2006)
Article
Astronomy & Astrophysics
AB Makalkin
SOLAR SYSTEM RESEARCH
(2004)
Article
Astronomy & Astrophysics
AB Makalkin, IN Ziglina
SOLAR SYSTEM RESEARCH
(2004)
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Geochemistry & Geophysics
VA Dorofeeva, AB Makalkin
GEOCHEMISTRY INTERNATIONAL
(2003)
Article
Astronomy & Astrophysics
VV Busarev, VA Dorofeeva, AB Makalkin
EARTH MOON AND PLANETS
(2003)
Article
Astronomy & Astrophysics
AB Makalkin, EL Ruskol
SOLAR SYSTEM RESEARCH
(2003)