Matter under Extreme Conditions

732. WE-Heraeus-Seminar

20 Oct - 23 Oct 2020


Online Conference (Zoom)

Scientific organizers:

Prof. Dr. Ronald Redmer, U Rostock • Dr. Gerd Steinle-Neumann, Bayerisches Geoinstitut, U Bayreuth • Dr. Zuzana Konôpková, European XFEL GmbH, Schenefeld

With the detection of the first extrasolar planet in orbit around a main sequence star in 1995 began a new era of planetary and astrophysics. To this day, almost 4000 exoplanets have been detected, and of approximately 700 we know both the radius and mass and therefore an average density which permits a classification of exoplanets. Among the various different types of exoplanets discovered, (i) super-Earths and (ii) mini-Neptunes have generated a specific interest in planetology. These classes represent planets with (i) an average density similar to that of the terrestrial planets in our solar system and a mass of up to 10 ME, and (ii) the density of the ice giants with a mass of a few ME,  respectively. At the center of a super-Earth with 5 ME, pressure reaches values of 2 TPa and temperatures are expected in the range of 8,000 K. In order to characterize the internal structure of exoplanets and to decrease uncertainty on their composition, knowledge of physical properties of planetary matter at these conditions is required:

  • Thermodynamic properties provide information on the internal structure of the planet via equations-of-state, and density distribution within the planet in turn permits the prediction of observables such as moment of inertia or the fluid Love number.
  • Electric and thermal conductivity determine whether a planet may operate a dynamo and thereby generate a magnetic field. The (indirect) observation of magnetic fields of exoplanets has just begun in astronomy.

Advances in high pressure generation using both static and dynamic techniques as well as the in-situ characterization of samples give access to the relevant conditions for the first time, provide parameters for planetary modelling, and permit a cross-check for material properties computed using ab-initio methods.

Goals of the seminar
In this WE-Heraeus seminar we plan to bring together scientists from the different fields involved in order to initiate an exchange of ideas, offer translations between them and align research interests beyond the group already involved in such research. We have identified scientists from both modelling and observational planetology, high-pressure generation and analytical physics and chemistry as well as computational physics that show interest in extrasolar planet research and can facilitate such a discussion. The seminar will be organized in four topical sessions:

  • Interior structure and dynamics of exoplanets: rocky and icy bodies
  • Ab-initio modelling for planetary materials in the TPa range
  • Experiments towards the TPa regime
  • Diagnostics of ionized planetary matters

The WE-Heraeus seminar gives a general introduction into each of these topics with an overview lecture and two topical talks. This setup makes it ideally suited for students, Ph.D. students and postdoctoral researchers who are interested in the field. Young researchers are given the opportunity to contribute to the seminar in the poster sessions and a small number of contributed talks.

The conference language will be English.