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Radiative lifetime of the $A$ ${}^{2}Π_{1 / 2}$ state in RaF with relevance to laser cooling

M. Athanasakis-Kaklamanakis ^1,2,3,*, S. G. Wilkins^4,5, P. Lassègues², L. Lalanne¹, J. R. Reilly⁶, O. Ahmad², M. Au ^7,8, S. W. Bai⁹, J. Berbalk² et al.

C. Bernerd⁷, A. Borschevsky ¹⁰, A. A. Breier ^11,12, K. Chrysalidis⁷, T. E. Cocolios ², R. P. de Groote ², C. M. Fajardo-Zambrano ², K. T. Flanagan ^6,13, S. Franchoo¹⁴, R. F. Garcia Ruiz^4,5, D. Hanstorp¹⁵, R. Heinke⁷, P. Imgram ², Á. Koszorús^1,2, A. A. Kyuberis ¹⁰, J. Lim ³, Y. C. Liu⁹, K. M. Lynch ⁶, A. McGlone ⁶, W. C. Mei⁹, G. Neyens ^2,†, L. Nies ¹, A. V. Oleynichenko ¹⁶, A. Raggio ¹⁷, S. Rothe⁷, L. V. Skripnikov ¹⁶, E. Smets², B. van den Borne ², J. Warbinek^18,19, J. Wessolek ^6,7, and X. F. Yang ⁹

¹Experimental Physics Department, CERN, CH-1211 Geneva 23, Switzerland
²KU Leuven, Instituut voor Kern- en Stralingsfysica, B-3001 Leuven, Belgium
³Centre for Cold Matter, Imperial College London, London SW7 2AZ, United Kingdom
⁴Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
⁵Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
⁶Department of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
⁷Systems Department, CERN, CH-1211 Geneva 23, Switzerland
⁸Department of Chemistry, Johannes Gutenberg-Universität Mainz, D-55128 Mainz, Germany
⁹School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100971, China
¹⁰Van Swinderen Institute of Particle Physics and Gravity, University of Groningen, NL-9747 CP Groningen, Netherlands
¹¹Institut für Optik und Atomare Physik, Technische Universität Berlin, D-10623 Berlin, Germany
¹²Laboratory for Astrophysics, Institute of Physics, University of Kassel, D-34132 Kassel, Germany
¹³Photon Science Institute, The University of Manchester, Manchester M13 9PY, United Kingdom
¹⁴Laboratoire Irène Joliot-Curie, CNRS/IN2P3 and University Paris-Saclay, 91405 Orsay, France
¹⁵Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden
¹⁶Affiliated with an institute covered by a cooperation agreement with CERN
¹⁷Department of Physics, University of Jyväskylä, FI-40014 Jyväskylä, Finland
¹⁸GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
¹⁹Department of Chemistry - TRIGA Site, Johannes Gutenberg-Universität Mainz, D-55128 Mainz, Germany

^*Contact author: m.athkak@cern.ch
^†Contact author: gerda.neyens@kuleuven.be

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Phys. Rev. A 110, L010802 – Published 22 July, 2024

DOI: https://doi.org/10.1103/PhysRevA.110.L010802

Abstract

The radiative lifetime of the $A {}^{2}Π_{1 / 2}$ $(v = 0)$ state in radium monofluoride (RaF) is measured to be 35(1) ns. The lifetime of this state and the related decay rate $Γ = 2.86 (8) \times 10^{7}$ $s^{- 1}$ are of relevance to the laser cooling of RaF via the optically closed $A {}^{2}Π_{1 / 2} \leftarrow X {}^{2}Σ_{1 / 2}$ transition, which makes the molecule a promising probe to search for new physics. RaF is found to have a comparable photon-scattering rate to homoelectronic laser-coolable molecules. Owing to its highly diagonal Franck-Condon matrix, it is expected to scatter an order of magnitude more photons than other molecules when using just three cooling lasers, before it decays to a dark state. The lifetime measurement in RaF is benchmarked by measuring the lifetime of the $8 P_{3 / 2}$ state in Fr to be 83(3) ns, in agreement with literature.

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Phys. Rev. A 110, L010802– Published 22 July, 2024

Vol. 110, Iss. 1 — July 2024

Received 14 March 2024
Accepted 31 May 2024

DOI: https://doi.org/10.1103/PhysRevA.110.L010802

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Open access publication funded by CERN.

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Radiative lifetime of the $A$ ${}^{2}Π_{1 / 2}$ state in RaF with relevance to laser cooling

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Radiative lifetime of the A Π1/22 state in RaF with relevance to laser cooling

Abstract

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References (37)

Radiative lifetime of the $A$ ${}^{2}Π_{1 / 2}$ state in RaF with relevance to laser cooling