Ultracold YbF molecules to measure the electron's electric dipole moment.

Informations projet

UCEEDM

N° de convention de subvention: 895187

DOI

10.3030/895187

Projet clôturé

Date de signature de la CE 16 Avril 2020

Date de début 1 Juin 2020

Date de fin 31 Mai 2022

Financé au titre de

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Coût total

€ 212 933,76

Contribution de l’UE

€ 212 933,76

Coordonné par

IMPERIAL COLLEGE OF SCIENCE TECHNOLOGY AND MEDICINE
United Kingdom

Periodic Reporting for period 1 - UCEEDM (Ultracold YbF molecules to measure the electron's electric dipole moment.)

Période du rapport: 2020-06-01 au 2022-05-31

Résumé du contexte et des objectifs généraux du projet

The purpose of this fellowship was to build an instrument for measuring the electron's electric dipole moment (eEDM) with a precision better than 10^30 e cm, with a longer term prospect of reaching below 10^31 e cm. This measurement will test new theories beyond the Standard Model (BSM) of particle physics and search for the undiscovered forces responsible for the observed asymmetry between matter and anti-matter in the Universe. Many BSM theories introducing new CP violating interactions to account for this asymmetry predict an eEDM many order of magnitude larger than in the standard model.

Travail effectué depuis le début du projet jusqu’à la fin de la période considérée dans le rapport et principaux résultats atteints jusqu’à présent

A new instrument was built for measuring the electron's electric dipole moment (eEDM). The instrument is based on a beam of ultracold YbF molecules. A key result was the development of a slow beam of YbF molecules. Another key result was direct laser cooling of YbF molecules to below 100 microkelvin. This produces a bright, highly collimated beam that is well suited for measuring the eEDM. The laser cooling was characterised in detail with respect to all the key control parameters. Highly efficient molecule detectors were built and characterised. A scheme to optically pump the molecules into the quantum state needed for the eEDM measurement was developed and tested. A magnetically-shielded eEDM interaction region was developed and the magnetic noise in this region was characterised in detail.

Progrès au-delà de l’état des connaissances et impact potentiel prévu (y compris l’impact socio-économique et les conséquences sociétales plus larges du projet jusqu’à présent)

The YbF molecule has been cooled in two dimensions for the first time. The temperature and number of cold molecules achieved are state of the art.
The machine built has the required characteristics (beam brightness, interaction time, detection noise, magnetic noise) to reach a state of the art sensitivity on the eEDM measurement in a near future.

Mechanical drawing of the new eEDM machine.

The ultracold eEDM experiment, with its electric field plates in the glass tube chamber.