Castel Pablo Juan Francisco, Cebrián Guajardo Susana, Dafni Theopisti, Díez Ibáñez David, Galán Lacarra Javier, García Pascual Juan Antonio, Ezquerro Sastre Álvaro, García Irastorza Igor, Luzón Marco Gloria, Margalejo Blasco Cristina, Mirallas Sánchez Héctor, Obis Aparicio Luis, Ortiz de Solórzano Alfonso, Pérez Lázaro Óscar, Porrón Lafuente Jorge, Jiménez Puyuelo María
Center for Astroparticles and High Energy Physics (CAPA), University of Zaragoza, Zaragoza, Aragon, Spain.
Open Res Eur. 2025 Mar 18;5:53. doi: 10.12688/openreseurope.19258.2. eCollection 2025.
We develop the concept of a Micromegas readout plane with an additional GEM preamplification stage placed a few millimetres above it to increase the maximum effective gain of the combined readout.
We implement it and test it in realistic conditions for its application to low-background dark matter searches like the TREX-DM experiment. For this, we use a Micromegas of Microbulk type, built with radiopure materials.
We report on GEM effective extra gain factors of about 90, 50 and 20 in 1, 4 and 10 bar of Ar-1%iC H . These results are obtained in a small test chamber allowing for systematic scanning of voltages and pressures. In addition, a TREX-DM full-scale set-up has also been built and tested, featuring a replica of the fully-patterned TREX-DM Microbulk readout.
The results here obtained show promise to lower the threshold of the experiment down to 50 eV , corresponding to substantially enhanced sensitivity to low-mass WIMPs.
我们提出了一种Micromegas读出平面的概念，在其上方几毫米处增加一个GEM前置放大级，以提高组合读出的最大有效增益。
我们将其实现并在实际条件下进行测试，以应用于像TREX-DM实验这样的低本底暗物质搜索。为此，我们使用了由无放射性材料制成的微块型Micromegas。
我们报告了在1巴、4巴和10巴的Ar-1%iC H 中，GEM的有效额外增益因子分别约为90、50和20。这些结果是在一个小型测试腔中获得的，该测试腔允许对电压和压力进行系统扫描。此外，还构建并测试了一个TREX-DM全尺寸装置，其具有完全图案化的TREX-DM微块读出的复制品。
此处获得的结果有望将实验阈值降低至50 eV ，这对应于对低质量弱相互作用大质量粒子的灵敏度大幅提高。
