Solar neutrinoelectron scattering as background limitation for double-beta decay

• Published in: Journal of physics. G, Nuclear and particle physics Nuclear and particle physics, 2011-10, Vol.38 (10)
• Main Authors: de Barros, N F, Zuber, K
• Format: Article
• Language: English
• ISSN: 0954-3899; 1361-6471
• DOI: 10.1088/0954-3899/38/10/105201

The background on double beta decay searches due to elastic electron scattering of solar neutrinos of all double beta emitters with Q-value larger than 2 MeV is calculated, taking into account survival probability and flux uncertainties of solar neutrinos. This work determines the background level to be 1 − 2 × 10 −7 counts keV −1 kg −1 yr −1, depending on the precise Q-value of the double beta emitter. It is also shown that the background level increases dramatically if going to lower Q-values. Furthermore, studies are done for various detector systems under consideration for next generation experiments. It was found that experiments based on loaded liquid scintillator have to expect a higher background. Within the given nuclear matrix element uncertainties any approach exploring the normal hierarchy has to face this irreducible background, which is a limitation on the minimal achievable background for purely calorimetric approaches. Large scale liquid scintillator experiments might encounter this problem already while exploring the inverted hierarchy. Potential caveats by using more sophisticated experimental setups are also discussed. Solar neutrino-electron scattering as background limitation for double beta decay 2