Detailed studies of $^{100}$Mo two-neutrino double beta decay in NEMO-3

R. Arnold (1) , C. Augier (2) , A.S. Barabash , A. Basharina-Freshville , S. Blondel (2) , S. Blot , M. Bongrand (2) , D. Boursette (2) , V. Brudanin , J. Busto (3) , A.J. Caffrey , S. Calvez (2) , M. Cascella , C. Cerna (4) , J.P. Cesar , A. Chapon (5) , E. Chauveau (4) , A. Chopra , L. Dawson , D. Duchesneau (6) , D. Durand (5) , R. Dvornický , V. Egorov , G. Eurin (2) , J.J. Evans , L. Fajt , D. Filosofov , R. Flack , X. Garrido (2) , C. Girard-Carillo (2) , H. Gómez (2) , B. Guillon (5) , P. Guzowski , R. Hodák , A. Huber (4) , P. Hubert (4) , C. Hugon (4) , S. Jullian (2) , O. Kochetov , S.I. Konovalov , V. Kovalenko , D. Lalanne (2) , K. Lang , Y. Lemière (5) , T. Le Noblet (6) , Z. Liptak , X.R. Liu , P. Loaiza (2) , G. Lutter (4) , M. Macko (4) , C. Macolino (2) , F. Mamedov , C. Marquet (4) , F. Mauger (5) , A. Minotti (6) , B. Morgan , J. Mott , I. Nemchenok , M. Nomachi , F. Nova , F. Nowacki (1) , H. Ohsumi , G. Oliviéro (5) , R.B. Pahlka , C. Patrick , F. Perrot (4) , A. Pin (4) , F. Piquemal (4, 7) , P. Povinec , P. Pridal , Y.A. Ramachers , A. Remoto (6) , J.L. Reyss (8) , C.L. Riddle , E. Rukhadze , R. Saakyan , A. Salamatin , R. Salazar , X. Sarazin (2) , J. Sedgbeer , Yu. Shitov , L. Simard (2) , F. Simkovic , A. Smetana , K. Smolek , A. Smolnikov , S. Söldner-Rembold , B. Soulé (4) , I. Stekl , J. Suhonen , C.S. Sutton , G. Szklarz (2) , H. Tedjditi (3) , J. Thomas , V. Timkin , S. Torre , Vl.I. Tretyak , V.I. Tretyak , V.I. Umatov , I. Vanushin , C. Vilela , V. Vorobel , D. Waters , F. Xie , A. Zukauskas

1 IPHC - Institut Pluridisciplinaire Hubert Curien
2 LAL - Laboratoire de l'Accélérateur Linéaire
3 CPPM - Centre de Physique des Particules de Marseille
4 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan
5 LPCC - Laboratoire de physique corpusculaire de Caen
6 LAPP - Laboratoire d'Annecy de Physique des Particules
7 LSM - UMR 6417 - Laboratoire Souterrain de Modane
8 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]

The full data set of the NEMO-3 experiment has been used to measure the half-life of the two-neutrino double beta decay of$^{100}$ Mo to the ground state of$^{100}$ Ru, $T_{1/2} = \left[ 6.81 \pm 0.01\,\left( \text{ stat }\right) ^{+0.38-0.40}\,\left( \text{ syst }\right) \right] \times 10^{18}$  year. The two-electron energy sum, single electron energy spectra and distribution of the angle between the electrons are presented with an unprecedented statistics of $5\times 10^5$ events and a signal-to-background ratio of $\sim $ 80. Clear evidence for the Single State Dominance model is found for this nuclear transition. Limits on Majoron emitting neutrinoless double beta decay modes with spectral indices of $\mathrm{n}=2,3,7$ , as well as constraints on Lorentz invariance violation and on the bosonic neutrino contribution to the two-neutrino double beta decay mode are obtained.

Mots clés: double-beta decay: (0neutrino); electron: energy spectrum; nucleus: transition; invariance: Lorentz; violation: Lorentz; decay modes; ground state; statistics; spectral; Majoron; S029MT; S076H2N

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

R. Arnold, C. Augier, A.S. Barabash, A. Basharina-Freshville, S. Blondel, et al.. Detailed studies of $^{100}$Mo two-neutrino double beta decay in NEMO-3. European Physical Journal C: Particles and Fields, 2019, 79 (5), pp.440. ⟨10.1140/epjc/s10052-019-6948-4⟩. ⟨hal-02097242⟩