Amaro Fernando Domingues, Antonietti Rita, Baracchini Elisabetta, Benussi Luigi, Bianco Stefano, Campagnola Roberto, Capoccia Cesidio, Caponero Michele, Cardoso Danilo Santos, de Carvalho Luan Gomes Mattosinhos, Cavoto Gianluca, Costa Igor Abritta, Croce Antonio, Dané Emiliano, Dho Giorgio, Di Giambattista Flaminia, Di Marco Emanuele, D'Astolfo Melba, D'Imperio Giulia, Fiorina Davide, Iacoangeli Francesco, Islam Zahoor Ul, Lima Jùnior Herman Pessoa, Kemp Ernesto, Maccarrone Giovanni, Mano Rui Daniel Passos, Marcelo Gregorio Robert Renz, Marques David José Gaspar, Mazzitelli Giovanni, McLean Alasdair Gregor, Messina Andrea, Meloni Pietro, Monteiro Cristina Maria Bernardes, Nobrega Rafael Antunes, Pains Igor Fonseca, Paoletti Emiliano, Passamonti Luciano, Petrucci Fabrizio, Piacentini Stefano, Piccolo Davide, Pierluigi Daniele, Pinci Davide, Prajapati Atul, Renga Francesco, Roque Rita Joana da Cruz, Rosatelli Filippo, Russo Alessandro, Dos Santos Joaquim Marques Ferreira, Saviano Giovanna, Silva Pedro Alberto Oliveira Costa, Spooner Neil John Curwen, Tesauro Roberto, Tomassini Sandro, Torelli Samuele
LIBPhys, Department of Physics, University of Coimbra, 3004-516 Coimbra, Portugal.
Dipartimento di Matematica e Fisica, Università Roma TRE, 00146 Rome, Italy.
Eur Phys J C Part Fields. 2024;84(10):1122. doi: 10.1140/epjc/s10052-024-13471-5. Epub 2024 Oct 29.
The CYGNO experiment aims to build a large ( m ) directional detector for rare event searches, such as nuclear recoils (NRs) induced by dark matter (DM), such as weakly interactive massive particles (WIMPs). The detector concept comprises a time projection chamber (TPC), filled with a He:CF 60/40 scintillating gas mixture at room temperature and atmospheric pressure, equipped with an amplification stage made of a stack of three gas electron multipliers (GEMs) which are coupled to an optical readout. The latter consists in scientific CMOS (sCMOS) cameras and photomultipliers tubes (PMTs). The maximisation of the light yield of the amplification stage plays a major role in the determination of the energy threshold of the experiment. In this paper, we simulate the effect of the addition of a strong electric field below the last GEM plane on the GEM field structure and we experimentally test it by means of a 10 10 cm readout area prototype. The experimental measurements analyse stacks of different GEMs and helium concentrations in the gas mixture combined with this extra electric field, studying their performances in terms of light yield, energy resolution and intrinsic diffusion. It is found that the use of this additional electric field permits large light yield increases without degrading intrinsic characteristics of the amplification stage with respect to the regular use of GEMs.
CYGNO实验旨在建造一个大型（ m ）定向探测器，用于搜寻罕见事件，例如由暗物质（DM）引起的核反冲（NRs），如弱相互作用大质量粒子（WIMPs）。探测器概念包括一个时间投影室（TPC），在室温和大气压下填充He:CF 60/40闪烁气体混合物，配备由三个气体电子倍增器（GEM）堆叠组成的放大阶段，该放大阶段与光学读出装置相连。后者由科学互补金属氧化物半导体（sCMOS）相机和光电倍增管（PMT）组成。放大阶段光产额的最大化在确定实验能量阈值方面起着重要作用。在本文中，我们模拟了在最后一个GEM平面下方添加强电场对GEM场结构的影响，并通过一个10×10 cm 读出面积的原型进行了实验测试。实验测量分析了不同GEM堆叠以及气体混合物中氦浓度与这种额外电场相结合的情况，研究了它们在光产额、能量分辨率和本征扩散方面的性能。结果发现，使用这种额外电场能够在不降低放大阶段相对于常规使用GEM时的本征特性的情况下大幅提高光产额。
