Welcome to the Website of nuClock!

nuClock is a European project headed for an ambitious goal: the development of a scientific clock that reaches a much higher precision compared to the best clocks that are operated today in some of the world’s finest laboratories. While such clocks use the electrons of an atom as the “pendulum”, we will use the nucleus of a very special atom – Thorium-229 – for setting the rhythm. Once we get our clock working, it can be employed aboard navigation satellites, it can help to synchronize networks, and it might lead astronomers to a better understanding of the universe.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 664732. It will run from 2015 to 2019. Stay with us: it’s sure going to be exciting!



New paper on collective effects in Thorium-doped crystals

Brenden, Wen-Te, and Adriana of MPIK in Heidelberg have released a new paper investigating collective effects that could occur in Thorium doped crystals when excited by narrow-band coherent pulses. Here's the link to the paper. A variety of schemes are discussed with the goal of creating unique signatures of excitation which can be used to determine the detuning of the exciting laser pulses from 229Th nuclear transition energy. Other details such as multi pulsed excitation, pulse shape, phase shifting…

Theoretical and experimental work leads to a redetermination of the Th-229 isomer charge radius

Marianna Safronova and colleagues from the Univ. of Delaware and from the Kurchatov Institute in St. Petersburg have performed new atomic structure calculations for Th+and Th2+that are used to relate measured spectroscopic isotope shifts to differences of the nuclear charge radii. Such calculations are notoriously difficult for these thorium ions because of strong configuration mixing of the electrons. Combined with experimental data on isotope shifts in Th+from 227Th to 232Th, measured at KfK Karlsruhe…

Hertha-Sponer-Prize for Adriana Pálffy-Buß

Adriana Pálffy-Buß is awarded the prestigeous Herta-Sponer-Prize from the German Physical Society (DPG) for her pathfinding reasearch on quantum effects in the interaction of atomic nuclei with X-ray pulses. Here's the link to the press release. Congratulations Adriana!

Tomas Sikorsky joins TU Wien Thorium Team

Starting with October 22., Tomas Sikorsky is enforcing the TU Wien Thorium team. Tomas has worked on NMR during his masters and on ion collisions with ultra cold gasses during his PhD in the team of Roee Ozeri at Weizmann. In Vienna, he will establish detection of the Thorium isomer via nuclear quadrupole resonance spectroscopy (NQRS). Welcome Tomas!

Lars von der Wense wins DPG thesis prize

Every year, the German Physics Society (DPG) offers a PhD thesis prize for each of its sections. This year, Lars von der Wense of LMU Munich was awarded the thesis prize in the section "Matter and Cosmos". Congratulations to Lars, his supervisor Peter G. Thirolf, and the whole team at LMU for this prestigious recognition!

EFTF in Torino: EFTF Award 2018 goes to Ekkehard Peik

This year's European Frequency and Time Forum (EFTF) is already the 32nd edition of this conference series and will take place in Torino, Italy, during the upcoming week. This conference is one of the global gathering of researchers involved with the measurement and distribution of time and frequencies; the conference webpage can be found here. Each year, a European Time and Frequency Award is given to an outstanding researcher to recognize his or her work. This year's EFTF Laureate is Ekkehard Peik…

New experimental values for the Th-229m isomer energy and lifetime

The Th-229 nuclear isomer has been around for more than 40 years already, but two of its main properties, namely its energy and lifetime, are known only with very large error margins. While there is no experimental value for the bare isomer lifetime at all, there is at least some consensus on the isomer energy (somewhere between 6.3 and 10 eV). In their recent study (now available on the arXiv preprint server here), the Russian group at MEPhI suggests an energy of 7.1 eV and a lifetime of about half…

New publication on the joint TU Wien & PTB work to directly excite the isomer

The TU Wien group and the Metrology Light Source (MLS) in Berlin (a part of PTB) have joined forces to directly excite the Thorium isomer in the VUV. In a measurement campaign about a year ago, Th-229 doped crystals were illuminated by tunable undulator radiation at the MLS facility. A wavelength region between 124 and 240 nm was probed (5.2 to 10 eV) at illumination & detection times between 30 and 600 seconds. The result of this study has now been made available on the arXiv preprint server…