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Neutrino-less Double Beta Decay of 48Ca studied by CaF2(Eu) Scintillators

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 Added by Saori Umehara
 Publication date 2008
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and research's language is English




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We searched for the neutrino-less double beta decay(0nbb) of 48Ca by using CaF2(Eu) scintillators. Analysis of their pulse shapes was effective to reduce backgrounds. No events are observed in the Q-value region for the data of 3394 kg days. It gives a lower limit (90% confidence level) of T > 2.7 x 10^22 year for the half life of 0nbb of 48Ca. Combined with our previous data for 1553 kg days, we obtained more stringent limit of T > 5.8 x 10^22 year.



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138 - Y. Iwata , N. Shimizu , Y. Utsuno 2014
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