Paper

Radon-induced backgrounds in the NEXT-100 experiment

Esteve, R, Romeo, B, Álvarez, V, Toledo, J F, Valle, P R G, Cossío, F P, Pazos, A, Ayyad, Y, Martín-Albo, J, Jones, B J P, M Pérez Maneiro, Herrero-Gómez, P, Silva, A L M, Torelli, S, Hernando Morata, J A, Auria-Luna, F, Teixeira, J M R, Madigan, R, Carrete, C Hervés, Querol, M, Simón, A, Azevedo, C D R, Castillo, A, Molina-Canteras, J, Novella, P, Isabel, A F B, Renner, J, Coupe, R, García-Barrena, J, Saharia, P, Soleti, S R, Torrent, J, Almazán, H, Ayet, S, Cid, X, P A O C Silva, M del Barrio-Torregrosa, Monrabal, F, Yubero-Navarro, A, Gómez-Cadenas, J J, NEXT Collaboration, Henriques, C A O, Rogers, L, Herrero, V, Marques, A P, J M F dos Santos, Miller, R L, Tonnelé, C, Parmaksiz, I, Lebrun, P, Vanga, M, P Vázquez Cabaleiro, Teruel-Pardo, S, J F C A Veloso, Barcelon, J E, Mistry, K, Martínez, A, Ruiz-Chóliz, E, Sorel, M, Villamil, J D, Dietz, P, Seemann, M, Dey, E, Trettin, A, Freixa, Z, Monteiro, C M B, Felkai, R, Mora, F J, Ballester, F, Elorza, M, Arnquist, I J, Nygren, D R, Benlloch-Rodríguez, J M, Santos, F P, Shomroni, I, Marauri, A, Rivilla, I, Para, A, Ferrario, P, Brodoline, A, Conde, C A N, Osborne, I, Fernandes, L M P, Cid, M, Pelegrin,

2026

Overview

The NEXT-100 detector at the LSC aims at the first competitive search for the decay using a high-pressure 136 electroluminescent time projection chamber. The first low-background run of NEXT-100 at 3.95 bar has been devoted to the measurement of the radon-induced backgrounds impacting this search. The contributions from both the internal and external airborne radon have been evaluated. The internal 222 activity is found to be (0.95\\(\\)0.04(stat)\\(\\)0.09(sys)) Bq/m\\(^3\\), while no traces of 220 have been observed. Most of the 222 progeny plate-out on the surface of the cathode of the detector, leading to a rate of Rn-induced 214 of (0.97\\(\\)0.05(stat)\\(\\)0.10(sys)) Hz for visible energies above 400 keV. The corresponding background index in the region of interest is evaluated as (7.3\\(\\)1.5(stat)\\(\\)0.8(sys))\\(10^-4\\) counts/(keV\\(\\)kg\\(\\)yr) after selection of the fully contained events. This background index is reduced to \\(\\)4\\(10^-5\\) counts/(keV\\(\\)kg\\(\\)yr) by applying a topological selection requiring only one double-electron-like track in the events. This value is one order of magnitude below the total radiogenic background expectation in NEXT-100. By analyzing the correlation of the airborne radon activity and the measured rate of events in NEXT-100, it is concluded that the detector operates in a virtually radon-free environment thanks to the radon abatement system of the LSC.

• Publisher: Cornell University Library, arXiv.org
• Subject: Radiation counters / Radon / Sensors