PhD ceremony: Ms. M. Ranjan, 14.30 uur, Academiegebouw, Broerstraat 5, Groningen
Dissertation: Design and characterization of a Cryogenic Stopping Cell for radioactive ions
Promotor(s): prof. N. Kalantar-Nayestanaki
Faculty: Mathematics and Natural Sciences
In-flight radioactive ion beam facilities deliver radioactive ions at very high energies. Studies requiring low-energy ions, e.g. using laser techniques and atom and ion traps, thus need the transformation of these high-energy ions into a low-energy ion beam. For this purpose, a so-called “Cryogenic Stopping Cell” was developed at KVI, University of Groningen. In this device, energetic radioactive ions are stopped in a noble gas (helium in the present work) and transported towards the exit side using a static electric field. At the exit side, a state-of-the-art radiofrequency carpet guides the ions to a small exit-hole from which they are extracted as a low-energy beam. Cryogenic operation ensures the required stopping gas purity.
The Cryogenic Stopping Cell is designed for use at the Fragment Separator at the GSI Helmholtz Centre for Heavy Ion Research and the Super-Fragment Separator to be installed at the Facility for Antiproton and Ion Research (FAIR) under construction at GSI (Darmstadt, Germany).
The Cryogenic Stopping Cell is the first of its kind. It was successfully validated by experiments using radioactive sources and high-energy radioactive ions from the Fragment Separator facility. The stopping cell was operated at a density almost two times higher than ever reached before. The technology used will allow to use even higher densities. The results represent a milestone in the stopping-cell development around the world.
Inspired by the importance of the European Wadden Sea for migratory birds, last week China successfully nominated parts of its own Wadden Sea - in the Yellow Sea - for the Unesco World Heritage Status. This means that the list of protected areas is...
The University of Groningen (UG) and Wageningen University & Research (WUR) have decided to work together more closely in the area of nature-inclusive and circular agriculture, and the rural development associated with this, in the Northern Netherlands...
Thirteen researchers from the University of Groningen (UG) and the UMCG have been awarded Veni grants within the framework of NWO’s Innovational Research Incentives Scheme.
A terrific result building on last year's successes, where 12 Groningen researchers...