MOON for neutrino-less double beta decays

H. Ejiri; P. Doe; S. R. Elliott; J. Engel; M. Finger; M. Finger; K. Fushimi; V. Gehman; M. Greenfield; R. Hazama; P. Kavitov; V. Kekelidze; H. Nakamura; M. Nomachi; R. G.H. Robertson; T. Shima; M. Slunecka; G. Shirkov; A. Sissakian; A. Titov; S. Umehara; V. Vaturin; V. Voronov; J. F. Wilkerson; D. I. Will; S. Yoshida; V. Vrba

doi:10.1140/epjst/e2008-00799-2

2023 Impact factor 2.6

Special Topics

Eur. Phys. J. Special Topics 162, 239-250 (2008)
https://doi.org/10.1140/epjst/e2008-00799-2

Majorana neutrinos by spectroscopic studies of double beta decays

H. Ejiri¹^,2^,3, P. Doe⁴, S. R. Elliott⁵, J. Engel⁶, M. Finger Jr.⁷, M. Finger⁷, K. Fushimi⁸, V. Gehman⁵, M. Greenfield⁹, R. Hazama¹⁰, P. Kavitov¹¹, V. Kekelidze¹², H. Nakamura², M. Nomachi¹³, R. G.H. Robertson⁴, T. Shima¹, M. Slunecka⁷, G. Shirkov¹², A. Sissakian¹², A. Titov¹², S. Umehara¹³, V. Vaturin¹¹, V. Voronov¹², J. F. Wilkerson⁴, D. I. Will⁴, S. Yoshida¹⁴ and V. Vrba¹⁵

¹ RCNP, Osaka University, Ibaraki, Osaka 567-0047, Japan
² National Institute of Radiological Sciences, Chiba 263-8555, Japan
³ Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Brehova, Prague, Czech Republic
⁴ CENPA, University Washington, Seattle, WA 98195, USA
⁵ LANL, PO Box 1663, MSH 803, Las Alamos, NM 87545, USA
⁶ Physics and Astronomy, Univ. North Carolina, Chapel Hill, NC 27599, USA
⁷ Charles University, FMP, CZ-18000 Praha 8, Czech Republic
⁸ IAS, University of Tokushima, Tokushima 770-8592, Japan
⁹ Physics, International Christian University, Tokyo 181-8585, Japan
¹⁰ Hiroshima University, Higashi Hiroshima, Hiroshima 739-8527, Japan
¹¹ VNIIEF, Nizhny Novgorod Region, Mira Ave 37, 607188 Sarov, Russia
¹² Joint Institute for Nuclear Research, 141980 Dubna, Russia
¹³ OULNS, Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
¹⁴ RCNS, Tohoku University, Sendai 980-8578, Japan
¹⁵ Institute of Physics, Akademy of Science, CZ-182 21 Praha 8, Czech Republic

Corresponding author: ejiri@rcnp.osaka-u.ac.jp

Abstract

The MOON (Majorana/Mo Observatory Of Neutrinos) project aims at studies of the Majorana nature of the neutrino ( $\nu$ ) and the $\nu$ -mass spectrum by spectroscopic experiments of neutrino-less double beta decays ( $0\nu \beta \beta$ ) with the $\nu$ -mass sensitivity of $\langle m_{\nu}^m \rangle = 100$ –30 meV. The solid scintillator option of the MOON detector is a super ensemble of multi-layer modules, each being composed by PL scintillator plates and position-sensitive detector planes with good overall energy resolution of $\sigma \approx 2\%$ at the $Q_{\beta \beta } \approx 3\,{\rm MeV}$ . Thin $\beta \beta$ source films are interleaved between the detector planes. High localization of the two $\beta$ tracks enables one to select true signals and reject BG ones. The multi-layer structure of the detector makes it realistic to build a compact ton-scale detector. MOON with detector $\ne \beta \beta$ source is used for studying $0\nu \beta \beta$ decays from $^{100}{\rm Mo}$ , ⁸²Se and other $\beta \beta$ isotopes with large $Q_{\beta \beta }$ . Real-time exclusive measurements of low energy solar neutrinos can be made by observing inverse $\beta$ rays from solar-ν captures of $^{100}{\rm Mo}$ in delayed coincidence with the subsequent β decay of ¹⁰⁰Tc.