The Vienna research group is affiliated with the Vienna University of Technology and situated at a very unique location: the Atominstitut (Institute for Atomic and Subatomic Physics), which houses a TRIGA Mark II nuclear reactor. The institute features research groups from the realms of nuclear and X-ray physics, neutron physics, as well as quantum optics, making it an ideal setting for the thorium research, which is inherently located at the border line between atomic and nuclear physics. The institute also features a full-fledged radiochemistry department, where radioactive samples for the whole consortium will be processed.

The Vienna group has already a few years of experience in the growing and characterization of CaF2 crystals doped with thorium. For this purpose, an arsenal of gadgets have been assembled: a furnace for crystal growing, devices to cut and polish the crystals, a UV spectrometer for transparency measurements, as well as two chambers with VUV excitation sources (such as an Excimer laser) and detection instruments (PMTs). The crystal growing process will be continuously improved to reduce the level of radio- and photoluminescence of the crystals; the initial search for the isomer transition will then be performed at the MLS synchrotron in Berlin. Once the transition wavelength has been determined with sufficient accuracy, precision spectroscopy with lasers will be performed.

The coordination of the consortium, both on the administrative and on the science side, will be executed by the Vienna group. Currently, there are eleven people working on the thorium project.


Thorsten Schumm


Thorsten Schumm TU Wien

Stephan Schneider

Project management financial & legal

Stephan Schneider TU Wien

Nadine Hilmar


Nadine Hilmar TU Wien

Sonja Laschet

Project management accounting

Tomas Sikorsky

Postdoc, Crystals, NQR, optical detection

Tomas Sikorsky TU Wien

Kjeld Beeks

PhD, Crystals, NQR, optical detection

Kjeld Beeks TU Wien

Veronika Rosecker

PhD, Radiochemistry

Veronika Rosecker TU Wien




Enikoe Seres

Staff Scientist, VUV frequency comb

Jozsef Seres

Staff Scientist, VUV frequency comb

Martin Pimon

PhD, crystal simulations (Theory)

Fabian Schaden

PhD, Crystals, NQR, optical detection

Georgy Kazakov

PostDoc, Theory