Project Details
Projekt
The radiation-hydrodynamics of photoevaporative winds with chemistry
Applicant
Professorin Barbara Ercolano, Ph.D.
Subject Area
Astrophysics and Astronomy
Term
since 2017
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 325594231
The formation of planetary systems out of the circumstellar material surrounding young solar type and lower mass young stars is a complex process, which is intimately linked with the evolution and dispersal of the planet-forming disc itself.High energy radiation from the young and active central star has an important role in driving the evolution of the disc. In particular X-rays which can penetrate a large column of gas, are responsible for ionisinig the gas, thus allowing a coupling with magnetic fields threading the disc. Furthermore they heat the atmosphere of discs, such that vigorous photoevaporative winds are established.During Phase I of the Research Unit our group has produced the most advanced and comprehensive ($>$ 400 models) library of two-dimensional radiation hydrodynamic photoevaporation models of discs spanning observed parameter space in stellar and disc masses, X-ray luminosity, size of central cavity and elemental abundances in the gaseous phase. These models provide important ingredients to planet and disc population synthesis models and we plan to exploit them in Phase II. We aim at revealing the true nature of so-called transition disks, i.e. dics with central cavities, by the mean of disk population models.Given the importance of providing the correct prescription of photoevaporation to the community, we will also engage in a detailed set of tests aimed at validating our method, by running a number of two dimensional radiation hydrodynamic simulations with chemistry solved on the fly. The new methods and codes developed in project B2 during Phase I (Grassi et al. 2020) puts us in a prime position to attend to this task, , also investigating the nature of discrepancies between different models reported in the literature (e.g. Wang \& Goodman, 2017; Nakatani et al. 2018ab).Finally, the interplay of photoevaporation with (giant) planet formation will be explored for the first time with three-dimensional radiation hydrodynamic calculations of photoevaporating discs containing giant planet(s). We will be able to study the effect of photoevaporation on the accretion flows on planets forming/migrating in the 1-80 au region of solar type stars, where X-ray photoevaporation is mostly active. We will pay attention on how this process may affect migration, as well as derive insights on the transport of solids and gas across a planetary gap in the presence of photoevaporation. In collaboration with project B2, observational signatures of this process will be sought by the analysis of possible wind diagnostics.
DFG Programme
Research Units
International Connection
United Kingdom
Co-Investigators
Dr. Tommaso Grassi; Professor Dr. Wilhelm Kley (†)
Cooperation Partner
Dr. James Owen
