Drift time calibration of the ultra-low material budget GEM-based TPC for MIXE

X. Zhao; M. W. Heiss; F. Garcia; B. J. Zeh; I. Briki; K. J. Flöthner; G. Janka; L. Scharenberg; B. Banto-Oberhauser; H. Müller; S. Biswas; T. Prokscha; A. Amato

arXiv · 2501.10249

Drift time calibration of the ultra-low material budget GEM-based TPC for MIXE

X. Zhao·M. W. Heiss·F. Garcia·B. J. Zeh·I. Briki·K. J. Flöthner·G. Janka·L. Scharenberg·B. Banto-Oberhauser·H. Müller·S. Biswas·T. Prokscha·A. Amato

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Abstract

Muon-Induced X-ray Emission (MIXE) is a non-destructive analytical technique that leverages negative muons to probe elemental and isotopic compositions by detecting characteristic muonic X-rays emitted during atomic cascades and gamma rays from nuclear capture processes. By controlling the muon beam momentum, MIXE enables depth-resolved analysis, spanning microns to centimeters, making it ideal for studying compositional variations in fragile, valuable, or operando samples. To enhance its capabilities, we integrated a twin Time Projection Chamber (TPC) tracker with Gas Electron Multiplier (GEM) amplification stages, allowing precise measurement of muon trajectories. A custom-built fiber detector with scintillating fibers and a Silicon Photomultiplier (SiPM) provides permille-level accuracy in drift velocity calibration, essential for accurate spatial reconstruction. This advanced setup correlates muon stopping points with X-ray emissions, paving the way towards element-sensitive imaging and establishing MIXE as a unique tool for high-resolution, depth-specific elemental analysis across diverse scientific applications.

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X. Zhao, M. W. Heiss, F. Garcia, B. J. Zeh, I. Briki, K. J. Flöthner, G. Janka, L. Scharenberg, B. Banto-Oberhauser, H. Müller, S. Biswas, T. Prokscha, A. Amato. 2025-01-17. Drift time calibration of the ultra-low material budget GEM-based TPC for MIXE. https://arxiv.org/abs/2501.10249

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