Doctoral Awards 2026

A surprise at the LHC:

First signs of toponium

Top quarks are the heaviest known elementary particles and decay in less than 10⁻²⁴ seconds. Whether they briefly bind with their antiparticle into a state called “toponium” beforehand was long considered nearly impossible to measure at the LHC.
During his PhD at the CMS experiment at CERN, Laurids Jeppe found exactly this signal: a statistically unambiguous excess of top quark pairs produced with minimal energy.  The result has since been confirmed by the ATLAS experiment as well. 
Whether unknown particles also contribute remains open. A future electron-positron collider could settle the question.
Before this, Jeppe presented the very first physics results of CMS at the record energy of 13.6 TeV of the LHC Run 3, only two months after the start of the data acquisition in the summer of 2022.

Viscosity measurement of molecular tritium at cryogenic temperatures for research and industry

Viscosity determines the flow behavior and pumpability of gases and is particularly relevant for the development of tritium pumps in fusion facilities, as well as in astroparticle physics as for the neutrino mass experiment KATRIN.
Thanks to the newly developed Cryogenic Viscosity Measurement Apparatus (Cryo-ViMA), Johanna Wydra was able, for the first time, to measure the viscosity of tritium with high precision between 100 K and 300 K, thereby fundamentally correcting previous models by mandatorily incorporating quantum mechanical and radiolytic effects. In doing so, she established a unique cryogenic measurement infrastructure at the Tritium Laboratory Karlsruhe (TLK) at KIT that is of great significance for fusion technology.
She successfully carried out this challenging research project as part of her doctoral work, supported by a family-friendly work environment while caring for her two young children.