D. Rodas-Rodríguez | Searcharxiv

arXiv2026

Production of GEM-like structures for cryogenic applications, using laser-cutting techniques

A novel concept for electroluminescence (EL) structures was recently proposed. In it, a wavelength-shifting material is deposited inside the holes of GEM-like structures which, after suitable optical treatment of its electrodes, improves the light collection and detection efficiency in noble gas TPCs. This new development directly addresses problems related with the scalability of future dual-phase TPCs for rare-event searches, matching (and potentially exceeding) the performance of conventional EL techniques. We report the newest developments on the production of such structures using laser-based techniques, namely the manufacture of a first batch of the so-called FAT-GEMs. This process allows low-cost and reproducible manufacturing of a high volume of such structures. In addition to the detailed description of the production, we present a performance assessment in pure argon, at a gas density close to the one expected in LAr conditions. An energy resolution of 23.5$\pm$1~\% (FWHM) at 5.9~keV was obtained, indicating a consistent improvement over previous batch. The optical treatment of the electrode surfaces has been greatly simplified and modestly improved, while charging-up effects arising from the use of laminates eliminated.

physics.ins-det↗

arXiv2024

On the determination of the interaction time of GeV neutrinos in large argon gas TPCs

Next-generation megawatt-scale neutrino beams open the way to studying neutrino-nucleus scattering using gaseous targets for the first time. This represents an opportunity to improve the knowledge of neutrino cross sections in the energy region between hundreds of MeV and a few GeV, of interest for the upcoming generation of long-baseline neutrino oscillation experiments. The challenge is to accurately track and (especially) time the particles produced in neutrino interactions in large and seamless volumes down to few-MeV energies. We propose to accomplish this through an optically-read time projection chamber (TPC) filled with high-pressure argon and equipped with both tracking and timing functions. In this work, we present a detailed study of the time-tagging capabilities of such a device, based on end-to-end optical simulations that include the effect of photon propagation, photosensor response, dark count rate and pulse reconstruction. We show that the neutrino interaction time can be reconstructed from the primary scintillation signal with a precision in the range of 1-2.5 ns ($σ$) for point-like deposits with energies down to 5 MeV. A similar response is observed for minimum-ionizing particle tracks extending over lengths of a few meters. A discussion on previous limitations towards such a detection technology, and how they can be realistically overcome in the near future thanks to recent developments in the field, is presented. The performance demonstrated in our analysis seems to be well within reach of next-generation neutrino-oscillation experiments, through the instrumentation of the proposed TPC with conventional reflective materials and a silicon photomultiplier array behind a transparent cathode.

physics.ins-det↗