Micromegas with GEM preamplification for enhanced energy threshold in low-background gaseous time projection chambers

Castel Pablo, Juan Francisco (Universidad de Zaragoza) ; Cebrián Guajardo, Susana (Universidad de Zaragoza) ; Dafni, Theopisti (Universidad de Zaragoza) ; Díez Ibáñez, David (Universidad de Zaragoza) ; Galán Lacarra, Javier ; García Pascual, Juan Antonio (Universidad de Zaragoza) ; Ezquerro Sastre, Álvaro (Universidad de Zaragoza) ; García Irastorza, Igor (Universidad de Zaragoza) ; Luzón Marco, Gloria (Universidad de Zaragoza) ; Margalejo Blasco, Cristina (Universidad de Zaragoza) ; Mirallas Sánchez, Héctor (Universidad de Zaragoza) ; Obis Aparicio, Luis ; Ortiz de Solórzano, Alfonso (Universidad de Zaragoza) ; Pérez Lázaro, Óscar (Universidad de Zaragoza) ; Porrón Lafuente, Jorge (Universidad de Zaragoza) ; Jiménez Puyuelo, María (Universidad de Zaragoza)

Resumen: Background 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. Methods 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. Results We report on GEM effective extra gain factors of about 90, 50 and 20 in 1, 4 and 10 bar of Ar-1%iC4H10. 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. Conclusions The results here obtained show promise to lower the threshold of the experiment down to 50 eV ee , corresponding to substantially enhanced sensitivity to low-mass WIMPs.

Idioma: Inglés

DOI: 10.12688/openreseurope.19258.2

Año: 2025

Publicado en: Open Research Europe 5 (2025), 53
ISSN: 2732-5121

Financiación: info:eu-repo/grantAgreement/EC/H2020/101026819/EU/Low background techniques on particle detectors for Rare Event Searches/LOBRES
Financiación: info:eu-repo/grantAgreement/EC/H2020/788781/EU/Towards the detection of the axion with the International Axion Observatory/IAXOplus
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2019-108122GB-C31
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2022-137268NB-C51

Tipo y forma: Article (Published version)

Área (Departamento): Proy. investigación HCA (Dpto. Física Teórica)
Área (Departamento): Área Física Atóm.Molec.y Nucl. (Dpto. Física Teórica)