Meet over 65 universities on 27 & 28 April > REGISTER NOW
Coventry University Featured PhD Programmes
University of Reading Featured PhD Programmes

Diamond Formation in Giant Ice Planets

Department of Physics

This project is no longer listed on and may not be available.

Click here to search for PhD studentship opportunities
Dr D Gericke Applications accepted all year round

About the Project

The internal structure of a planet, that is its radial material and density distribution, is largely defined by hydrostatic equilibrium:
in gas and icy giants like Jupiter and Neptune, respectively, the gas or plasma pressure of the compressed internal layers
must hold the weight of the upper layers. Thus, the phase and the pressure of the material as a function of compression are the
main ingredient for planet modelling. While the upper layers consist of usual gases that get more and more compressed, the
mantel of the planet is ionised, mostly, due to the high compression of the materials. Thus, one needs to understand both highly
compressed neutral gases as well as ionised matter under large pressures and at moderate temperature (few thousand degrees).
The most dramatic change to the structure of gas and ice giants is related to phase transition at large pressures. Such transitions
can prohibit convection (like the creation of clouds in the earth’s atmosphere) and, thus, may constitute layer boundaries with
different compositions on each side. In ice giants, we find a rich composition of gases in the observable layers: methane,
ammonia or water. Moreover, experiments and simulations have found a large range of phases when these materials are put
under the extreme pressures of the deeper layers of the planets. One of the most prominent predictions was the phase separation
of hydrogen and carbon from hydrocarbons. Based on this predictions, Ross ask in 1981 if there are ``diamonds in the sky?’’. It
took more than 30 years until this question could be answered positively by new laboratory experiments. However, the full range
of pressures and temperatures inside a planet is too large to be tested experimentally. Here, simulations and theory estimates are

The project will be based on the latest experimental finding on diamond formation in carbon and carbohydrates the under large
pressures in icy planets. It will determine the possible consequences of diamond formation and diamond rain for the inner structure
of icy planets which inludes a number of exoplanets with high carbon content. Question to be answered are the possible size
of the diamonds, the region of their occurrence, the energy release to to the sinking diamonds in the gravitational field etc. To
answer these questions, a new evolutionary model needs to be developed. Gaps in the experimental records should be closed by
ab initio simulations (tools exist). Moreover, the project will also support new experimental campaigns by providing predictions
and determination of important parameter regions within the existing collaboration.

Funding Notes

This is an STFC funded project. Enquiries and applications from interested students are welcome, with detailed information about the studentship scheme to follow. Candidates should hold or expect to hold a 1st (or high 2.1) in Physics or related subject area. See for further details.

The Physics department is proud to be an IOP Juno Champion and a winner of an Athena Swan Silver Award, reflecting our commitment to equal opportunity and to fostering an environment in which all can excel.
Search Suggestions

Search Suggestions

Based on your current searches we recommend the following search filters.

FindAPhD. Copyright 2005-2021
All rights reserved.