Virtual seminar at the accelerator: Sabina Markelj, Jožef Stefan Institute

Dr. Sabina Markelj from Jožef Stefan Institute, Ljubljana, Slovenia, will give us a virtual seminar where she will describe the future thermonuclear devices such as DEMO displacement damage by 14 MeV fusion neutrons will be created in the plasma-facing materials while they are exposed to high fluxes of ions and neutrals of hydrogen isotopes (HIs) at elevated temperatures. In the context of heavy-ion or neutron irradiation, displacement damage refers to displacement of lattice atoms from their equilibrium position in the crystal lattice and subsequent creation of lattice defects such as vacancies, self-interstitial atoms, vacancy clusters, voids and dislocation lines/loops. These lattice defects act as trapping sites for HIs with high de-trapping energy as compared to the energy of HI diffusion between solute interstitial sites.

 

She will give a short overview on the knowledge gained so far for displacement damaged tungsten (W) and interaction with HIs. As a surrogate for 14 MeV neutron irradiation they have used MeV energy W ions to create displacement damage in W. In order to be able to describe the interaction between HI and defects as well as the creation and evolution of defects and their dependence on temperature and HI flux one needs to isolate and understand the individual processes. For this purpose, they performed a set of experiments where individual aspects were addressed. She will describe the processes that are important at the hydrogen isotope interaction with defects in the crystal lattice. By the help of rate equation models the experiments enabled us to pin down the created traps and de-trapping energies and their concentrations. However, there is still ambiguity in determination what type of defects trap hydrogen. She will describe how ion channelling might be able to help in these studies, work planed within a Eurofusion Enabling project DeHydroC.

 

The seminar will be a virtual meeting in MS Teams platform. Please find enclosed the link to be used to connect to virtual meeting to be performed on Wednesday 22th at 15:30 pm:

https://teams.microsoft.com/l/meetup-join/19:420972c51ba747868e5abca2d1fb412d@thread.tacv2/1631869905055?context=%7B%22Tid%22:%22fc6602ef-8e88-4f1d-a206-e14a3bc19af2%22,%22Oid%22:%22c61b715d-f581-4c11-be3f-f746a5cb8b3b%22%7D

 

If you have an email not belonging to UAM, you should connect bringing up Google Chrome browser. Thus, just copy and paste the above link into the browser. On the other hand, those members owning an UAM email account just use your own institutional TEAMS. Again it is necessary to use the same link.