Electrostatic focusing of cold and heavy molecules for the ACME electron EDM search
The current best upper limit for electron electric dipole moment (EDM), | d _e | < 1.1 × 10 ^−29 e cm (90% confidence), was set by the ACME Collaboration in 2018. The ACME experiment uses a spin-precession measurement in a cold beam of thorium monoxide (ThO) molecules to detect d _e . An improvem...
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| Format: | Article |
| Language: | English |
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IOP Publishing
2022-01-01
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| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/ac8014 |
| _version_ | 1797748425598435328 |
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| author | X Wu P Hu Z Han D G Ang C Meisenhelder G Gabrielse J M Doyle D DeMille |
| author_facet | X Wu P Hu Z Han D G Ang C Meisenhelder G Gabrielse J M Doyle D DeMille |
| author_sort | X Wu |
| collection | DOAJ |
| description | The current best upper limit for electron electric dipole moment (EDM), | d _e | < 1.1 × 10 ^−29 e cm (90% confidence), was set by the ACME Collaboration in 2018. The ACME experiment uses a spin-precession measurement in a cold beam of thorium monoxide (ThO) molecules to detect d _e . An improvement in statistical uncertainty would be possible with more efficient use of molecules from the cryogenic buffer gas beam source. Here, we demonstrate electrostatic focusing of the ThO beam with a hexapole lens. This results in a factor of 16 enhancement in the molecular flux detectable downstream, in a beamline similar to that built for the next generation of ACME. We also demonstrate an upgraded rotational cooling scheme that increases the ground state population by 3.5 times compared to no cooling, consistent with expectations and a factor of 1.4 larger than previously in ACME. When combined with other demonstrated improvements, we project over an order of magnitude improvement in statistical sensitivity for the next generation ACME electron EDM search. |
| first_indexed | 2024-03-12T16:04:33Z |
| format | Article |
| id | doaj.art-654f18bc2d9d44b4ba6e0b01eb9e4a4e |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:04:33Z |
| publishDate | 2022-01-01 |
| publisher | IOP Publishing |
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| series | New Journal of Physics |
| spelling | doaj.art-654f18bc2d9d44b4ba6e0b01eb9e4a4e2023-08-09T14:25:27ZengIOP PublishingNew Journal of Physics1367-26302022-01-0124707304310.1088/1367-2630/ac8014Electrostatic focusing of cold and heavy molecules for the ACME electron EDM searchX Wu0https://orcid.org/0000-0002-6646-820XP Hu1Z Han2D G Ang3https://orcid.org/0000-0002-7501-7507C Meisenhelder4https://orcid.org/0000-0002-0339-5672G Gabrielse5J M Doyle6D DeMille7Department of Physics, University of Chicago , Chicago, IL 60637, United States of America; Department of Physics, Harvard University , Cambridge, MA 02138, United States of AmericaDepartment of Physics, University of Chicago , Chicago, IL 60637, United States of AmericaDepartment of Physics, University of Chicago , Chicago, IL 60637, United States of AmericaDepartment of Physics, Harvard University , Cambridge, MA 02138, United States of AmericaDepartment of Physics, Harvard University , Cambridge, MA 02138, United States of AmericaCenter for Fundamental Physics, Northwestern University , Evanston, IL 60208, United States of AmericaDepartment of Physics, Harvard University , Cambridge, MA 02138, United States of AmericaDepartment of Physics, University of Chicago , Chicago, IL 60637, United States of AmericaThe current best upper limit for electron electric dipole moment (EDM), | d _e | < 1.1 × 10 ^−29 e cm (90% confidence), was set by the ACME Collaboration in 2018. The ACME experiment uses a spin-precession measurement in a cold beam of thorium monoxide (ThO) molecules to detect d _e . An improvement in statistical uncertainty would be possible with more efficient use of molecules from the cryogenic buffer gas beam source. Here, we demonstrate electrostatic focusing of the ThO beam with a hexapole lens. This results in a factor of 16 enhancement in the molecular flux detectable downstream, in a beamline similar to that built for the next generation of ACME. We also demonstrate an upgraded rotational cooling scheme that increases the ground state population by 3.5 times compared to no cooling, consistent with expectations and a factor of 1.4 larger than previously in ACME. When combined with other demonstrated improvements, we project over an order of magnitude improvement in statistical sensitivity for the next generation ACME electron EDM search.https://doi.org/10.1088/1367-2630/ac8014electron EDMprecision measurementcold polar moleculeelectrostatic lens |
| spellingShingle | X Wu P Hu Z Han D G Ang C Meisenhelder G Gabrielse J M Doyle D DeMille Electrostatic focusing of cold and heavy molecules for the ACME electron EDM search New Journal of Physics electron EDM precision measurement cold polar molecule electrostatic lens |
| title | Electrostatic focusing of cold and heavy molecules for the ACME electron EDM search |
| title_full | Electrostatic focusing of cold and heavy molecules for the ACME electron EDM search |
| title_fullStr | Electrostatic focusing of cold and heavy molecules for the ACME electron EDM search |
| title_full_unstemmed | Electrostatic focusing of cold and heavy molecules for the ACME electron EDM search |
| title_short | Electrostatic focusing of cold and heavy molecules for the ACME electron EDM search |
| title_sort | electrostatic focusing of cold and heavy molecules for the acme electron edm search |
| topic | electron EDM precision measurement cold polar molecule electrostatic lens |
| url | https://doi.org/10.1088/1367-2630/ac8014 |
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