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# The XXX International Conference on Neutrino Physics and Astrophysics (Neutrino 2022)

30 May 2022 to 4 June 2022
Virtual Seoul
Asia/Seoul timezone

## Demonstration of Tl-208 backgrounds reduction for ZICOS experiment using topological information of Cherenkov light

Not scheduled
20m
Virtual Seoul

#### Virtual Seoul

Poster Neutrinoless double beta decay

### Speaker

Yoshiyuki Fukuda (Department of Physics, Faculty of Education, Miyagi University of Education)

### Description

ZICOS is a future experiment for 0$\nu \beta \beta$ of $^{96}$Zr nuclei. In order to achieve sensitivity over $10^{27}$ years, ZICOS will use tons of $^{96}$Zr, and need to remove $^{208}$Tl backgrounds as observed by KamLAND-Zen one order of magnitude. For this purpose, we have developed new technique to distinguish the signal and background using topology of Cherenkov light. We have measured directly this topology using HUNI-ZICOS detector and the results clearly indicated topology as effective even 1MeV electron. Also the pulse shape discrimination for the extraction of PMT which receives Cherenkov lights in the liquid scintillator has been established. In order to confirm above technique, we have demonstrated using $\beta - \gamma$ event such as $^{208}$Tl $\beta$ decay using $^{60}$Co source using UNI-ZICOS detector.

Here we will report present status and results obtained by recent measurement.

Collaboration Super-Kamiokande

### Primary authors

Yoshiyuki Fukuda (Department of Physics, Faculty of Education, Miyagi University of Education) Prof. Shigetaka Moriyama (Kamioka Obsrvatory, ICRR, University of Tokyo) Prof. Katsuki HIraide (Kamioka Observatory, ICRR, University of Tokyo) Prof. Izumi Ogawa (Applied Physics, Faculty of Engineering, University of Fukui) Prof. Takahiro Gunji (Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science) Prof. Shunsuke Kurosawa (Institute for Material Research, Tohoku University)