bb decay and neutrino mass 35 isotopes in nature Nottingham
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Nottingham Nov 17 ’04 bb decay and neutrino mass 35 isotopes in nature Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 Dirac neutrino vs Majorana neutrino Dirac C P T L R L R Majorana Lorentz Boost, E, B Thanks to Adam Para for this and several other slides. L R C P T Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 m mee U mk 2 ek k i ek U e mk ek 2 k Each is ±1 if CP conserved, but there can still be cancellations Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 2 1 t1 / 2 2 m M if (phase space ) me Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 0bb: Peak at Q-value of nuclear transition Sum energy spectrum of both electrons Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 100Mo NEMO-3 at 1025 years 2.7m Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 Neutrinoless BB-decay limits From Elliot and Vogel, hep-ph/0202264 Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 Neutrinoless BB-decay Future Projects Detector description T5y1/2(y) <m>* 130Te 10 kg CdTe semiconductors 1 x 1024 0.71 130Te 40 kg of TeO2 bolometers 1.5 x 1025 0.19 Sarazin et al 2000 100Mo 10 kg of bb(0n) isotopes (7 kg Mo) with tracking 4 x 1024 0.56 Arnaboldi et al. 2001 Danevich et al 2000 Zdesenko et al 2001 KlapdorKleingrothaus et al 2001 130Te 760 kg of TeO2 bolometers 7 x 1026 0.027 136Xe 8 x 1026 0.052 76Ge 1 t enriched Xe TPC 1 t enriched Ge diodes in liquid nitrogen + water shield 7 x 1027 0.018 76Ge 1 t enriched Ge diodes in liquid nitrogen 1 x 1028 0.015 4 x 1027 2 x 1025 > 1026 0.025 0.035 0.069 Experiment Author COBRA Zuber 2001 Arnaboldi et al 2001 CUORICINO NEMO3 CUORE EXO GEM GENIUS Isotope MAJORANA DCBA CAMEO Aalseth et al 2002 76Ge 0.5 t enriched Ge segmented diodes Ishihara et al 2000 150Nd 20 kg enriched Nd layers with tracking Bellini et al 2001 116Cd CANDLES Kishimoto et al 48Ca GSO Danevich 2001 160Gd MOON Ejiri et al 2000 100Mo 1 t CdWO4 crystals in liquid scintillator several tons of CaF2 crystal in liquid scintillator 2 t Gd2SiO5:Ce cristal scintillator in liquid scintillator 34 t natural Mo sheets between plastic scintillator Caccianiga et al 2001 Moriyama et al 2001 136Xe 136Xe Xe XMASS 1 x 1026 2 x 1026 0.065 1 x 1027 0.036 1.56 t of enriched Xe in liquid scintillator 5 x 1026 0.066 10 t of liquid Xe 3 x 1026 0.086 Dave Wark Imperial College/RAL Nottingham Nov 17 ’04 From Pascoli and Petcov, hep-ph/0205022 Normal hierarchy Inverted hierarchy Need new experiments to reach ~ 10 meV Dave Wark Imperial College/RAL
