Possible Thesis Topics
Today, nine states possess in total about 13'400 nuclear weapons. Additionally, they own 1250 t of weapon-grade uranium and 140 t of plutonium, which could be used to build thousands of additional weapons. In order to disarm existing weapons successfully and to prevent the construction of new weapons, it is crucial that robust, scientific methods exist to verify disarmament.
The Nuclear Verification and Disarmament group develops such methods, focusing on the reconstruction of fissile material production and on the authentication of nuclear warheads. We also work on preventing the proliferation of nuclear materials; specifically, we investigate how nuclear waste repositories can be monitored using antineutrino measurements to detect a diversion of nuclear waste.
Nuclear ArchaeologyCopyright: © Washington State Department of Ecology, Antonio Figueroa
We develop so-called n uclear archaeology methods to reconstruct the fissile material production histories of nuclear facilities . Specifically, we investigate how measurements of isotopic ratios in nuclear waste or in shut-down reactors could be used to infer , e.g., the runtime of a nuclear reactor and other operational parameters . Moreover , we research how to reconstruct fissile material production by considering the whole nuclear fuel cycle ; we simulat e the cycle from the mining of uranium to its disposal in a repository. Here, the material flows between facilities could help the re construction process and reduce uncertainties.
Please note that we will offer theses on nuclear archaeology from September 2022 onwards.
Antineutrino Measurements for Safeguards
Neutrinos below 5 MeV are of particular interest in neutrino physics, e.g. , for the study of solar neutrinos and geoneutrinos. This also applies to a new concept for monitoring radioactive waste repositories, which contain plutonium in the form of spent nuclear fuel . W e plan on measur ing antineutrinos produced by the radioactive isotopes present in the waste to monitor it and detect diversion . For this purpose, a Time Projection Chamber is being developed that uses an organic liquid to detect low-energy neutrinos.
We are working on simulations of the signature of antineutrino interactions in the detector as well as potential background. Further, we study the monitoring scenarios for nuclear waste repositories with these detectors. Together with the TPC group of physics institute IIIB we will also construct a first prototype detector.
Nuclear Warhead AuthenticationCopyright: © Christopher Fichtlscherer, Moritz Kütt
An essential process in nuclear disarmament verification is the authentication of nuclear weapons. This process ensures that an object is indeed a nuclear weapon. Authentication is usually based on measuring the radiation emit ted from nuclear weapons. Can a malicious actor replicate these emissions using other materials and thus cheat in the verification process? This question is still unanswered. Addressing this research gap is of fundamental importance to any nuclear disarmament and arms control efforts.
Our work is based on Monte Carlo simulations (e.g., Geant4 and OpenMC) and mathematical methods from various fields to review existing methods and develop new fraud-proof strategies to verify nuclear disarmament.
General remarks on writing your thesis at the NVD group
A major part of our work consists in model ling the problem in question using appropriate simulation tools and analyzing the results with various statistical methods. Thus, your thesis will focus on p rogramming , which will mostly be done in Python and, for certain projects, in C++ . You will either write your own code or expand already existing software. However, you do not need prior knowledge on nuclear reactors, nuclear weapons or specific simulation software. You will learn about these topics over the course of your thesis.