Speaker
OBARA shuhei
(Tohoku University)
Description
KamLAND-Zen is an experiment for neutrinoless double beta decay search with xenon 136 based on large liquid scintillator detector KamLAND. In order to reduce the cosmogenic isotopes and environmental radio-activities (Uranium, Thorium Potassium), KamLAND-Zen set 16.5m$^{3}$ xenon loaded scintillator in 25 $\mu$m thickness and 3.16 m diameter nylon balloon.
First phase of the experiment (KamLAND-Zen 400, 400 kg xenon gas) released a lower limit for the neutrinoless double beta decay half-life. But sensitivity is restricted by the contamination of balloon (mini-balloon) which is introduced by construction. Then KamLAND-Zen collaboration planed to upgrade the detector especially for the new mini-balloon which can contain 800 kg xenon gas with 31.4m$^{3}$ liquid scintillator in 3.84 m diameter (KamLAND-Zen 800).
We present the current status of KamLAND-Zen 800, new mini-balloon construction and methods to avoid the background contaminations.
Primary author
OBARA shuhei
(Tohoku University)
Co-author
Yoshihito Gando
(Tohoku Univ.)
