ﻻ يوجد ملخص باللغة العربية
Circumstellar discs may become warped or broken into distinct planes if there is a stellar or planetary companion with an orbit that is misaligned with respect to the disc. There is mounting observational evidence for protoplanetary discs with misaligned inner discs and warps that may be caused by such interactions with a previously undetected companion, giving us a tantalising indication of possible planets forming there. Hydrodynamical and radiative transfer models indicate that the temperature varies azimuthally in warped discs due to the variable angle at which the disc surface faces the star and this impacts the disc chemistry. We perform chemical modelling based on a hydrodynamical model of a protoplanetary disc with an embedded planet orbiting at a 12$^{circ}$ inclination to the disc. Even for this small misalignment, abundances of species including CO and HCO$^+$ vary azimuthally and this results in detectable azimuthal variations in submillimetre line emission. Azimuthal variations in line emission may therefore indicate the presence of an unseen embedded companion. Nonaxisymmetric chemical abundances should be considered when interpreting molecular line maps of warped or shadowed protoplanetary discs.
The Protoplanetary Discussions conference --- held in Edinburgh, UK, from 7th --11th March 2016 --- included several open sessions led by participants. This paper reports on the discussions collectively concerned with the multiphysics modelling of pr
We carry out three-dimensional hydrodynamical simulations to study planet-disc interactions for inclined high mass planets, focusing on the discs secular evolution induced by the planet. We find that, when the planet is massive enough and the induced
Damping of the previously discovered resonant drag instability (RDI) of dust streaming in protoplanetary disc is studied using the local approach to dynamics of gas-dust perturbations in the limit of the small dust fraction. Turbulence in a disc is r
Dark rings with bright rims are the indirect signposts of planets embedded in protoplanetary discs. In a recent first, an azimuthally elongated AU-scale blob, possibly a planet, was resolved with ALMA in TW Hya. The blob is at the edge of a cliff-lik
Until now, axisymmetric, alpha-disc models have been adopted for calculations of the chemical composition of protoplanetary discs. While this approach is reasonable for many discs, it is not appropriate when self-gravity is important. In this case, s