A new review paper on nuclear clocks

Researchers at LMU Munich have put together a new review paper on the history of work on the Th-229 isomer, its current status, as well as potential implementations of a nuclear clock. The paper also investigates the properties of other candidates (aside from Th-229) to be used for a nuclear clock. It was assembled in connection with a talk given by Lars von der Wense at last year’s 175th anniversary of the Mendeleev All-Russia Research Institute of Metrology (VNIIM) in St. Petersburg, and can be downloaded here.

Registration for nuClock conference NOCAN started

The nuClock consortium is set to organize a conference entitled NOCAN: Novel Optical Clocks in Atoms and Nuclei. The goal of the seminar is to discuss conceptually novel approaches to optical frequency standards and clocks. Despite the remarkable precision already realized in current atomic clock worldwide, there is a wide range of concepts for next-generation devices, rooted in very different physical systems. The aim of the seminar is to provide a comprehensive overview on the current state of discussion and shape a community. Also, we want to identify and discuss new applications of precision frequency and time standards, in particular regarding constraining possible variations of fundamental constants, clock-based geodesy, and gravitational wave detection.

Registration for the conference starts now: please find the webpage here, which includes a registration form and a template for submission of your abstract. We are looking forward to welcome you at the conference!

The list of already confirmed invited speakers:

Keynote talks:
· Ekkehard Peik
· Peter Thirolf
· Marianna Safronova
· Jose Ramon Crespo Lopez-Urrutia

Talks on the nuclear clock
· Koji Yoshimura
· Marcin Piotrowski
· Petr Borisyuk
· Thorsten Schumm
· Christian Enss
· Christian Schneider
· Eric Hudson
· Adriana Palffy
· Matthias Verlinde

Talks on novel approaches, applications, theory
· Julian Berengut
· Atsushi Yamaguchi
· Nils Huntemann
· Andrew Ludlow
· Michal Zawada
· Victor Flambaum
· Tanja Mehlstäubler
· Pacôme Delva
· David Champion
· Jean-Lautrier Gaud

Another five speakers for “Hot Topic Talks” will be selected from the submitted abstracts.

Theoretical work on the hyperfine structure of Th-229m

The hyperfine interaction of the nucleus with the electron shell leads to energy shifts of electronic transitions that are easily accessible to laser spectroscopy. Now that Th-229m ions in the isomeric state became available at the LMU experiment, the PTB group performed laser spectroscopy on these ions and compared the spectra with Th-229 ions in the nuclear ground state. These measurements allowed the two teams to learn a lot about the properties of the nucleus when it’s excited to the isomeric state (see the paper here). The value of the observed nuclear magnetic dipole moment, however, disagrees massively with previous calculations: this clearly calls for a clarification on the theory side.

New calculations performed by the PTB group can reproduce the experimental values to an excellent degree and thus help to better understand the Th-229m nucleus. This work has now been published here.

Thorium research at the DPG Spring Meeting

You want to meet the nuClock people and learn about the latest state of current research? Then head for the DPG meeting in Erlangen, which takes place March 5 – 9. Peter G. Thirolf of LMU Munich will give a plenary talk on Monday morning, and an entire session (A/Q 44) on Friday will be devoted to precision spectroscopy of nuclear systems. There will be five talks of nuClock people in this session! More information can be found here.

2017 nuClock meeting in Heidelberg a great success

Last week’s 3-day meeting in Heidelberg was a great success. With 33 participants, this was by far the largest nuClock meeting to date (Vienna 2014: 20 participants, Munich 2015: 24, Brussels 2016: 19). Aside from pretty much all the nuClock members, a large crowd of external guests joined the meeting: Koji Yoshimura from Okayama (Japan), Piet van Duppen and Matthias Verlinde from Leuven (Belgium), Nikolay Minkov from Sofia (Romania), Rukang Li, Xiaoyang Wang, Mingjun Xia, and Lijuan Liu from Beijing (China), Mustapha Laatiaoui and Christoph Düllmann from GSI, as well as the local MPIK fellows José Crespo, Sergey Eliseev and Klaus Blaum. A total of 22 talks were given, all of them showing exciting results or new ideas that will be published in the near future. Many thanks to Adriana for hosting the meeting!

The next nuClock meeting will take place in Bad Honnef, Germany, on July 9 – 12, 2018. This is going to be a large conference (approx. 100 participants), entitled “WE-Heraeus-Seminar: Novel Optical Clocks in Atoms and Nuclei”.

Group photo of the nuClock team 2017. Last row, left to right: Koji Yoshimura (Okayama), Rukang Li, Mingjun Xia, Lijuan Liu, and Xiaoyang Wang (all Chinese Academy of Sciences, Beijing), Przemyslaw Gkowacki and Maksim Okhapkin (both PTB). Third row: Andreas Fleischmann (KIP Heidelberg), Sarina Geldhof and Ilkka Pohjalainen (both Jyvälylä), Piet van Duppen and Matthias Verlinde (both KU Leuven), David-Marcel Meier (PTB), José Crespo (MPIK Heidelberg), Lars von der Wense (LMU Munich), Pavlo Bilous (MPIK Heidelberg). Second row: Jürgen Stuhler (Toptica AG), Peter G. Thirolf and Benedict Seiferle (LMU Munich), Johannes Weitenberg (MPQ Garching), Georgy Kazakov (TU Wien), Iain Moore (Jyväskylä), Nikolay Minov (Sofia). First row: Simon Stellmer (TU Wien), Annkatrin Sommer (Toptica AG), Thorsten Schumm and Kjeld Beeks (TU Wien), Brenden Nickerson (MPIK Heidelberg), Ekkehard Peik (PTB), and Adriana Palffy (MPIK Heidelberg). Not pictured here: Christoph Düllmann (GSI & Mainz).