First results of the search for neutrinoless double beta decay with the NEMO 3 detector

R. Arnold (1) , C. Augier (2) , J. Baker , A. Barabash , G. Broudin (3) , V. Brudanin , A.J. Caffrey , E. Caurier (1) , V. A. Egorov , K. Errahmane (2) , A.I. Etienvre (2) , J.L. Guyonnet (1) , F. Hubert (3) , P. Hubert (3) , C. Jollet (1) , Sophie Jullian (2) , O. Kochetov , V. V. Kovalenko , S. Konovalov , D. Lalanne (2) , F. Leccia (3) , C. Longuemare (4) , G. Lutter (3) , C. Marquet (3) , F. Mauger (4) , F. Nowacki (1) , H. Ohsumi , F. Piquemal (3) , J.L. Reyss , R. Saakyan , X. Sarazin (2) , L. Simard (2) , F. Simkovic , Yu. Shitov , A. Smolnikov , I. Stekl , J. Suhonen , C.S. Sutton , G. Szklarz (2) , J. Thomas , V. Timkin , V. Tretyak , V. Umatov , L. Vala , I. Vanushin , V. Vasilyev , V. Vorobel , Ts. Vylov

1 IReS - Institut de Recherches Subatomiques
2 LAL - Laboratoire de l'Accélérateur Linéaire
3 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan
4 LPCC - Laboratoire de physique corpusculaire de Caen

The NEMO 3 detector, which has been operating in the Frejus underground laboratory since February 2003, is devoted to the search for neutrinoless double beta decay ($\beta\beta0\nu$). Half-lives of the two neutrino double beta decays ($\beta\beta2\nu$) have been measured for $^{100}$Mo and $^{82}$Se. After 389 effective days of data collection from February 2003 until September 2004 (Phase I), no evidence for neutrinoless double beta decay was found from $\sim$ 7kg of $^{100}$Mo and $\sim$1 kg of $^{82}$Se. The corresponding lower limits for the half-lives are 4.6 $\times$ 10$^{23}$ years for $^{100}$Mo and 1.0 $\times10^{23}$ years for $^{82}$Se (90\% C.L.). Depending on the nuclear matrix elements calculation, limits for the effective Majorana neutrino mass are < 0.7-2.8 eV for $^{100}$Mo and < 1.7-4.9 eV for $^{82}$Se

Domaines: Physique des Hautes Energies - Expérience [hep-ex]

R. Arnold, C. Augier, J. Baker, A. Barabash, G. Broudin, et al.. First results of the search for neutrinoless double beta decay with the NEMO 3 detector. Physical Review Letters, 2005, 95, pp.182302. ⟨10.1103/PhysRevLett.95.182302⟩. ⟨in2p3-00024486⟩