Performance of the MORA Apparatus for Testing Time-Reversal Invariance in Nuclear Beta Decay

N. Goyal; A. Singh; S. Daumas-Tschopp; L. M. Motilla Martinez; G. Ban; V. Bosquet; J. F. Cam; P. Chauveau; S. Chinthakayala; G. Fremont; R. P. De Groote; F. de Oliveira Santos; T. Eronen; A. Falkowski; X. Flechard; Z. Ge; M. Gonzalez-Alonso; H. Guerin; L. Hayen; A. Jaries; M. Jbayli; A. Jokinen; A. Kankainen; B. Kootte; R. Kronholm; N. Lecesne; Y. Merrer; V. Morel; M. Mougeot; G. Neyens; J. Perronnel; M. Reponen; A. Raggio; S. Rinta-Antila; A. Rodriguez-Sanchez; N. Severijns; J. C. Thomas; C. Vandamme; S. Vanlangendonk; V. Virtanen; E. Lienard; I. D. Moore; P. Delahaye

arXiv · 2504.16957

Performance of the MORA Apparatus for Testing Time-Reversal Invariance in Nuclear Beta Decay

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Abstract

The MORA experimental setup is designed to measure the triple-correlation D parameter in nuclear beta decay. The D coefficient is sensitive to possible violations of time-reversal invariance. The experimental configuration consists of a transparent Paul trap surrounded by a detection setup with alternating beta and recoil-ion detectors. The octagonal symmetry of the detection setup optimizes the sensitivity of positron-recoil-ion coincidence rates to the D correlation, while reducing systematic effects. MORA utilizes an innovative in-trap laser polarization technique. The design and performance of the ion trap, associated beamline elements, lasers and beta and recoil-ion detectors, are presented. Recent progress towards the polarization proof-of-principle is described.

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N. Goyal, A. Singh, S. Daumas-Tschopp, L. M. Motilla Martinez, G. Ban, V. Bosquet, J. F. Cam, P. Chauveau, S. Chinthakayala, G. Fremont, R. P. De Groote, F. de Oliveira Santos, T. Eronen, A. Falkowski, X. Flechard, Z. Ge, M. Gonzalez-Alonso, H. Guerin, L. Hayen, A. Jaries, M. Jbayli, A. Jokinen, A. Kankainen, B. Kootte, R. Kronholm, N. Lecesne, Y. Merrer, V. Morel, M. Mougeot, G. Neyens, J. Perronnel, M. Reponen, A. Raggio, S. Rinta-Antila, A. Rodriguez-Sanchez, N. Severijns, J. C. Thomas, C. Vandamme, S. Vanlangendonk, V. Virtanen, E. Lienard, I. D. Moore, P. Delahaye. 2025-04-22. Performance of the MORA Apparatus for Testing Time-Reversal Invariance in Nuclear Beta Decay. https://arxiv.org/abs/2504.16957

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