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PA Colloquium Speaker Schedule Sign Up
Current PA Colloquium Schedule
Speaker = Prof. David Leibrandt of UCLA
Host = Xing Wu wux@frib.msu.edu
When = 2025-11-20 Thursday
Where = BPS 1415
Please feel free to sign up below, but note that some slots may need to be re-assigned to accommodate those with a specific need to meet the speaker. If this happens, the Admin or Speaker Host will reach out to you via email.
Wednesday November 19
| Start Time | End Time | Name | Building | Room |
|---|---|---|---|---|
| 11:30 | 13:00 | traveling from Ann Arbor | ||
| 13:00 | 13:30 | Xing Wu | FRIB | 2001 |
| 13:30 | 14:00 | Xing Wu | FRIB | 2001 |
| 14:00 | 14:30 | Jaideep Taggart Singh | FRIB | 2016 |
| 14:30 | 15:00 | Jaideep Taggart Singh | FRIB | 2016 |
| 15:00 | 15:30 | Nuclear Science Seminar Refreshments | FRIB | 1300 |
| 15:30 | 16:30 | Nuclear Science Seminar | FRIB | 1300 |
Thursday November 20
| Start Time | End Time | Name | Building | Room |
|---|---|---|---|---|
| 09:00 | 09:30 | Quest Lab | FRIB | 1344 |
| 09:30 | 10:00 | Quest Lab | FRIB | 1344 |
| 10:00 | 10:30 | Marcos Dantos | Chemistry | 58 |
| 10:30 | 11:00 | Marcos Dantos | Chemistry | 58 |
| 11:00 | 11:30 | Spinlab | FRIB | TBD |
| 11:30 | 12:00 | Spinlab | FRIB | TBD |
| 12:00 | 12:30 | Spinlab | FRIB | 1350 |
| 12:30 | 13:30 | Lunch with Graduate Students | BPS | 1400 |
| 13:30 | 14:00 | Chirag Vyas | FRIB | IHV |
| 14:00 | 14:30 | Chirag Vyas | FRIB | IHV |
| 14:30 | 15:00 | Johannes Pollanen | BPS | 4216 |
| 15:00 | 15:30 | PA colloquium prep | BPS | 1415 |
| 15:30 | 16:30 | PA colloquium | BPS | 1415 |
Friday November 21
| Start Time | End Time | Name | Building | Room |
|---|---|---|---|---|
| 09:00 | 09:30 | Witek Nazarewicz | FRIB | 2059 |
| 09:30 | 10:00 | Kei Minamisono | FRIB | 3103 |
| 10:00 | 10:30 | |||
| 10:30 | 11:00 | |||
| 11:00 | 11:30 | Jonas Becker | FRIB | Lobby |
| 11:30 | 12:00 | Jonas Becker | BPS | |
| 12:00 | 13:00 | PA Undergrad Lunch | BPS | 1400 |
| 13:00 | 13:30 | Franziska Maier | FRIB | 3101 |
| 13:30 | 14:00 | |||
| 14:00 | 14:30 | Shane Wilkins | FRIB | 2014 |
| 14:30 | 15:00 | Jaideep Taggart Singh | FRIB | 2016 |
| 15:00 | 15:30 | Ruby Ghosh | BPS | |
| 15:30 | 16:00 | Ruby Ghosh | BPS | |
| 16:00 | 16:30 | |||
| 16:30 | 17:00 |
Context
Title = Tests of fundamental physics with thorium nuclear clocks
Abstract
Clocks based on hyperfine and electronic transitions in laser-cooled atoms, with fractional inaccuracy and instability now reaching below 1e-18, have revolutionized positioning, navigation, and timekeeping (PNT) and serve as one of the experimental foundations on which the Standard Model of particle physics was built. A new type of clock based on the internal transitions of atomic nuclei, dubbed nuclear clocks, was proposed by Peik and Tamm in 2003. Among nuclei, the thorium-229 nucleus is unique in having a transition at low enough energy to be accessible with present-day laser technology, and laser spectroscopy of the 148 nm thorium-229 nuclear isomer transition was first demonstrated by three groups nearly simultaneously in 2024. Due to the higher energy scales and additional fundamental interactions present in the nucleus, nuclear transitions are much more sensitive to small deviations from the predictions of the Standard Model than atomic transitions. Beyond applications in PNT, thorium nuclear clocks may offer insights about the nature of dark matter or other hints about what lies beyond the Standard Model.
In this colloquium, I will begin with a brief overview of the thorium-229 nuclear isomer transition and the two experimental approaches currently being pursued to build thorium nuclear clocks: one based on thorium doped into solid-state hosts and the other based on trapped and laser-cooled thorium ions. Next, I will present the design and current status of a trapped-ion thorium clock experiment under construction in my lab at UCLA. Finally, I will conclude with a discussion of the fundamental physics reach of this and other thorium nuclear clocks.
Relevant background with commentary from Speaker
- TBD…
