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arXiv · 2111.00624

Improved algorithms for determination of particle directions with Timepix3

Petr Mánek·Benedikt Bergmann·Petr Burian·Declan Garvey·Lukáš Meduna·Stanislav Pospíšil·Petr Smolyanskiy·Eoghan White
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Abstract

Timepix3 pixel detectors have demonstrated great potential for tracking applications. With $256\times 256$ pixels, 55 $\mathrm{\mu}$m pitch and improved resolution in time (1.56 ns) and energy (2 keV at 60 keV), they have become powerful instruments for characterization of unknown radiation fields. A crucial pre-processing step for such analysis is the determination of particle trajectories in 3D space from individual tracks. This study presents a comprehensive comparison of regression methods that tackle this task under the assumption of track linearity. The proposed methods were first evaluated on a simulation and assessed by their accuracy and computational time. Selected methods were then validated with a real-world dataset, which was measured in a well-known radiation field. Finally, the presented methods were applied to experimental data from the Large Hadron Collider. The best-performing methods achieved a mean absolute error of 1.99{\deg} and 3.90{\deg} in incidence angle $\theta$ and azimuth $\varphi$, respectively. The fastest presented method required a mean computational time of 0.02 ps per track. For all experimental applications, we present angular maps and stopping power spectra.

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Petr Mánek, Benedikt Bergmann, Petr Burian, Declan Garvey, Lukáš Meduna, Stanislav Pospíšil, Petr Smolyanskiy, Eoghan White. 2021-10-31. Improved algorithms for determination of particle directions with Timepix3. https://doi.org/10.1088/1748-0221/17/01/c01062

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