Energy resolution and gain measurements in Argon-based gas mixtures: Exploring Ar:CF₄ for low energy measurements with TPCs

Journal Article · 09 May 2025 · Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment

DOI: https://doi.org/10.1016/j.nima.2025.170582 · OSTI ID:2566452

Randhawa, J. S.  ^[1]; Prokop, C. J. ^[2]; Gastis, P.  ^[2]; Kuvin, S. A. ^[2]; Lee, H. Y. ^[2]; Paneru, S. N.  ^[2]; Winkelbauer, J. ^[2]

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1. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Mississippi State University, Mississippi State, MS (United States)
2. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Time Projection Chambers (TPCs) are among the most advanced charged-particle detectors. Gas-filled TPCs have tracking capabilities that provide 3D-imaging of charged particles with a good energy resolution for spectroscopy. Different gas mixtures have different properties that determine the energy resolution as well as the spatial resolution. Therefore, optimization of operating conditions is required to simultaneously obtain adequate gain, energy resolution, spatial/track resolution, as well as higher drift velocities for high counting rates applications. Ar:CF₄ gas mixture has higher electron drift velocities and lower electron diffusion, which makes it an attractive candidate for TPC filling gas for low energy nuclear physics applications as compared to commonly used Ar:CH₄ and Ar:CO₂ gas mixtures, namely when tracking information is needed. However, other properties, including energy resolution and gain, remain largely unexplored in Ar:CF₄ especially at pressures and other operating conditions relevant for low-energy nuclear physics applications. Here, in this paper we report on gain and energy resolution measurements, using Gas Electron Multipliers (GEMs), in the less explored Ar:CF₄ mixture (Alfonsi et al., 2006), as well as in the more commonly used gas mixtures Ar:CH₄ and Ar:CO₂. In addition to obtaining energy resolution and gain, we provide results from Garfield++ simulations for gain fluctuations, and their impact on energy resolution is discussed.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 2566452
• Report Number(s): LA-UR--24-29217
• Journal Information: Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment, Journal Name: Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment Vol. 1078; ISSN 0168-9002
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English