Discovery potential of xenon-based neutrinoless double beta decay experiments in light of small angular scale CMB observations

• Published in: Journal of Cosmology and Astroparticle Physics
• Main Authors: Gómez Cadenas, Juan José, Martín-Albo, Justo, Peña-Garay, Carlos, Muñoz Vidal, Javier
• Other Authors: Ministerio de Economía y Competitividad (España), Generalitat Valenciana, European Commission
• Format: Article in Journal/Newspaper
• Language: English
• Published: Institute of Physics Publishing 2013
• Subjects: neutrino masses from cosmology; double beta decay; South Pole; South pole
• Online Access: http://hdl.handle.net/10261/124686; https://doi.org/10.1088/1475-7516/2013/03/043; https://doi.org/10.13039/501100003329; https://doi.org/10.13039/501100003359; https://doi.org/10.13039/501100000780

The South Pole Telescope (SPT) has probed an expanded angular range of the CMB temperature power spectrum. Their recent analysis of the latest cosmological data prefers nonzero neutrino masses, with Sigma m(nu) = (0.32 +/- 0.11) eV. This result, if con firmed by the upcoming Planck data, has deep implications on the discovery of the nature of neutrinos. In particular, the values of the effective neutrino mass m(beta beta) involved in neutrinoless double beta decay (beta beta 0 nu) are severely constrained for both the direct and inverse hierarchy, making a discovery much more likely. In this paper, we focus in xenon-based beta beta 0 nu experiments, on the double grounds of their good performance and the suitability of the technology to large-mass scaling. We show that the current generation, with effective masses in the range of 100 kg and conceivable exposures in the range of 500 kg.year, could already have a sizeable opportunity to observe beta beta 0 nu events, and their combined discovery potential is quite large. The next generation, with an exposure in the range of 10 ton.year, would have a much more enhanced sensitivity, in particular due to the very low specific background that all the xenon technologies (liquid xenon, high-pressure xenon and xenon dissolved in liquid scintillator) can achieve. In addition, a high-pressure xenon gas TPC also features superb energy resolution. We show that such detector can fully explore the range of allowed effective Majorana masses, thus making a discovery very likely. We warmly acknowledge C. González-García and P. Hernández for discussions, help and insight. This work was supported by the Ministerio de Economía y Competitividad of Spain under grants CONSOLIDER-Ingenio 2010 CSD2008-0037 (CUP), FPA2009-13697-C04-04 and FPA2011-29678, and by the Generalitat Valenciana grant PROMETEO/2009/116 and the ITN INVISIBLES (Marie Curie Actions, PITN-GA-2011-289442). Peer reviewed