eEDM:Measurement of the electron electric dipole moment
Lead Research Organisation:
Imperial College London
Department Name: Physics
Abstract
The Standard Model of elementary particle physics predicts that the electric dipole moment of the electron (eEDM) is far too small to measure. However, modern extensions to the standard model - e.g. supersymmetric theories or other theories with additional particles or fields - predict values in the range accessible to experiment. Hence, the eEDM measurement is a search for physics beyond the standard model. Since a permanent electron EDM violates time-reversal symmetry, it is also deeply connected to the important issue of CP violation and the apparent asymmetry between matter and antimatter in the universe. We are now in the middle of making the most sensitive eEDM measurement to date, a measurement that tests theories of new physics. Our method uses laser manipulation of cold polar molecules, which will eventually be trapped at ultra-low temperature. This approach has the promise of improving on the precision of the eEDM search by 2-3 orders of magnitude compared with the current best measurement. In this rolling-grant proposal, we are seeking support for an ongoing programme of development that will allow us to realise this promise. This offers the exciting prospect of either detecting a non-zero eEDM or excluding a large fraction of the models for new physics.
Organisations
Publications
Hinds E
(2009)
Cold Molecules - Theory, Experiment, Applications
Hudson J
(2007)
Pulsed beams as field probes for precision measurement
in Physical Review A
Kara D
(2012)
Measurement of the electron's electric dipole moment using YbF molecules: methods and data analysis
in New Journal of Physics
Sauer BE
(2008)
A robust floating nanoammeter.
in The Review of scientific instruments
Skoff S
(2011)
Diffusion, thermalization, and optical pumping of YbF molecules in a cold buffer-gas cell
in Physical Review A
Skoff S
(2009)
Doppler-free laser spectroscopy of buffer-gas-cooled molecular radicals
in New Journal of Physics
Tarbutt M
(2008)
Nonlinear dynamics in an alternating gradient guide for neutral particles
in New Journal of Physics
Tarbutt M.R.
(2009)
Preparation and manipulation of molecules for fundamental physics tests
in Cold Molecules: Theory, Experiment, Applications
Tarbutt MR
(2009)
Prospects for measuring the electric dipole moment of the electron using electrically trapped polar molecules.
in Faraday discussions
Wall T
(2009)
Transport of polar molecules by an alternating-gradient guide
in Physical Review A
Description | (a) We have completed an edm measurement at the 5 10^{-28}e.cm level. This is the best measurement of the electron edm in the world. (b) We have developed a molecule decelerator for YbF. (c) We have developed the world's most intense slow molecule source, but have not yet integrated it into the experiment because our funding was stopped. (d) This source would improve the statistical sensitivity to 5 10^{-29}e.cm (e) Since we have not integrated the new source into the experiment we have not attempted an edm measurement at the 5 10^{-29} level (f) We have evaluated the potential of trapped molecules for edm measurements and find that slow beams are better. |
Exploitation Route | This is fundamental research concerning the laws of physics at very high energy. No patentable or commercially exploitable intellectual property resulted from it. |
Sectors | Energy |
Description | Our result was reported on the BBC news, on National Public Radio (USA), in the Times, Guardian, and Telegraph and in the national newspapers of many other countries. Interviews were broadcast on BBC Radio News, on the radio 4 programme Material World, and on BBC 3-counties radio. Our measurement even prompted a joke on Radio 4 comedy programme The News Quiz. People are fascinated that the simple question "is the electron round" connects with such deep issues as the relation between matter and antimatter and the physics of the early universe. This type of impact inspires young students to take up science and excites the public in general. Public interest is a prerequisite for engaging politicians in science. |
First Year Of Impact | 2011 |
Sector | Energy |
Description | An improved measurement of the electron electric dipole moment using YbF molecules |
Amount | £913,892 (GBP) |
Funding ID | EP/J011401/1 |
Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
Sector | Public |
Country | United Kingdom |
Start | 03/2012 |
End | 01/2017 |
Description | ERC Advanced Grants |
Amount | £1,853,561 (GBP) |
Funding ID | 320789 |
Organisation | European Research Council (ERC) |
Sector | Public |
Country | Belgium |
Start | 02/2013 |
End | 01/2018 |
Description | PPRP 2018 |
Amount | £1,263,790 (GBP) |
Funding ID | ST/S000011/1 |
Organisation | Science and Technologies Facilities Council (STFC) |
Sector | Public |
Country | United Kingdom |
Start | 10/2018 |
End | 09/2022 |
Description | Particle Physics Consolidated Grant - Measurement of the eEDM |
Amount | £724,632 (GBP) |
Funding ID | ST/N000242/1 |
Organisation | Science and Technologies Facilities Council (STFC) |
Sector | Public |
Country | United Kingdom |
Start | 10/2015 |
End | 09/2019 |
Description | Research Grant - Measurement of the electron edm: eEDM (CG) |
Amount | £83,183 (GBP) |
Funding ID | ST/K001604/1 |
Organisation | Science and Technologies Facilities Council (STFC) |
Sector | Public |
Country | United Kingdom |
Start | 10/2012 |
End | 09/2016 |
Description | Revealing the undiscovered forces that break matter-antimatter symmetry by measuring the shape of electrons (Templeton) |
Amount | £888,745 (GBP) |
Funding ID | 61104 |
Organisation | The John Templeton Foundation |
Sector | Academic/University |
Country | United States |
Start | 10/2018 |
End | 06/2021 |
Description | The study of elementary particles and their interactions (Consolidated Grant 2019 - 2022) |
Amount | £14,105,169 (GBP) |
Funding ID | ST/S000739/1 |
Organisation | Science and Technologies Facilities Council (STFC) |
Sector | Public |
Country | United Kingdom |
Start | 10/2019 |
End | 09/2022 |