Radiopurity assessment of the tracking readout for the NEXT double beta decay experiment
Abstract
The Neutrino Experiment with a Xenon Time-Projection Chamber (NEXT) is intended to investigate the neutrinoless double beta decay of 136Xe, which requires a severe suppression of potential backgrounds; therefore, an extensive screening and selection process is underway to control the radiopurity levels of the materials to be used in the experimental set-up of NEXT. The detector design combines the measurement of the topological signature of the event for background discrimination with the energy resolution optimization. Separate energy and tracking readout planes are based on different sensors: photomultiplier tubes for calorimetry and silicon multi-pixel photon counters for tracking. The design of a radiopure tracking plane, in direct contact with the gas detector medium, was specially challenging since the needed components like printed circuit boards, connectors, sensors or capacitors have typically, according to available information in databases and in the literature, activities too large for experiments requiring ultra-low background conditions. Here, the radiopurity assessment of tracking readout components based on gamma-ray spectroscopy using ultra-low background germanium detectors at the Laboratorio Subterraneo de Canfranc (Spain) is described. According to the obtained results, radiopure enough printed circuit boards made of kapton and copper, silicon photomultipliers and other required components, fulfilling the requirement of an overall background level in the region of interest of at most 8 10-4 counts keV-1 kg-1 y-1, have been identified.
Keywords
Cite
@article{arxiv.1411.1433,
title = {Radiopurity assessment of the tracking readout for the NEXT double beta decay experiment},
author = {S. Cebrián and J. Pérez and I. Bandac and L. Labarga and V. Álvarez and A. I. Barrado and A. Bettini and F. I. G. M. Borges and M. Camargo and S. Cárcel and A. Cervera and C. A. N. Conde and E. Conde and T. Dafni and J. Díaz and R. Esteve and L. M. P. Fernandes and M. Fernández and P. Ferrario and A. L. Ferreira and E. D. C. Freitas and V. M. Gehman and A. Goldschmidt and J. J. Gómez-Cadenas and D. González-Díaz and R. M. Gutiérrez and J. Hauptman and J. A. Hernando Morata and D. C. Herrera and I. G. Irastorza and A. Laing and I. Liubarsky and N. López-March and D. Lorca and M. Losada and G. Luzón and A. Marí and J. Martín-Albo and A. Martínez and G. Martínez-Lema and T. Miller and F. Monrabal and M. Monserrate and C. M. B. Monteiro and F. J. Mora and L. M. Moutinho and J. Muñoz Vidal and M. Nebot-Guinot and D. Nygren and C. A. B. Oliveira and A. Ortiz de Solórzano and J. L. Pérez Aparicio and M. Querol and J. Renner and L. Ripoll and J. Rodríguez and F. P. Santos and J. M. F. dos Santos and L. Serra and D. Shuman and A. Simón and C. Sofka and M. Sorel and J. F. Toledo and J. Torrent and Z. Tsamalaidze and J. F. C. A. Veloso and J. A. Villar and R. C. Webb and J. T. White and N. Yahlali},
journal= {arXiv preprint arXiv:1411.1433},
year = {2015}
}