R2D2 spherical TPC: first energy resolution results

R. Bouet; J. Busto; V. Cecchini; C. Cerna; A. Dastgheibi-Fard; F. Druillole; C. Jollet; P. Hellmuth; I. Katsioulas; P. Knights; I. Giomataris; M. Gros; P. Lautridou; A. Meregaglia; X. F. Navick; T. Neep; K. Nikolopoulos; F. Perrot; F. Piquemal; M. Roche; B. Thomas; R. Ward; M. Zampaolo

doi:10.1088/1748-0221/16/03/p03012

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arXiv · 2007.02570

R2D2 spherical TPC: first energy resolution results

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Abstract

Spherical time projection chambers (TPC), also known as spherical proportional counters, are employed in the search for rare phenomena, such as light Dark Matter candidates. The spherical TPC exhibits a number of essential features, making it a promising candidate for the search of neutrinoless double beta decay ($\beta\beta0\nu$). A tonne-scale spherical TPC experiment could cover a region of parameter space relevant for the inverted mass hierarchy with a few years of data taking. In this direction, the major R\&D goal of the R2D2 effort is the demonstration of the required energy resolution. First results from an argon-filled prototype detector are reported, demonstrating an energy resolution of 1.1\% FWHM for 5.3~MeV $\alpha$ tracks in the 0.2 to 1.1~bar pressure range. This is a major milestone in terms of energy resolution, paving the way for further studies with xenon gas, and the possible use of this technology for $\beta\beta0\nu$ searches.

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R. Bouet, J. Busto, V. Cecchini, C. Cerna, A. Dastgheibi-Fard, F. Druillole, C. Jollet, P. Hellmuth, I. Katsioulas, P. Knights, I. Giomataris, M. Gros, P. Lautridou, A. Meregaglia, X. F. Navick, T. Neep, K. Nikolopoulos, F. Perrot, F. Piquemal, M. Roche, B. Thomas, R. Ward, M. Zampaolo. 2020-07-06. R2D2 spherical TPC: first energy resolution results. https://doi.org/10.1088/1748-0221/16/03/p03012

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