Detection efficiency and spatial resolution of Monolithic Active Pixel Sensors bent to different radii

Anton Andronic; Pascal Becht; Mihail Bogdan Blidaru; Giuseppe Eugenio Bruno; Francesca Carnesecchi; Emma Chizzali; Domenico Colella; Manuel Colocci; Giacomo Contin; Laura Fabbietti; Roman Gernhäuser; Hartmut Hillemanns; Nicolo Jacazio; Alexander Philipp Kalweit; Alex Kluge; Artem Kotliarov; Filip Křížek; Lukas Lautner; Magnus Mager; Paolo Martinengo; Silvia Masciocchi; Marius Wilm Menzel; Alice Mulliri; Felix Reidt; Riccardo Ricci; Roberto Russo; David Schledewitz; Gilda Scioli; Serhiy Senyukov; Sabyasachi Siddhanta; Jory Sonneveld; Johanna Stachel; Miljenko Šuljić; Nicolas Tiltmann; Arianna Grisel Torres Ramos; Berkin Ulukutlu; Gianluca Usai; Jacob Bastiaan Van Beelen; Yitao Wu; Alperen Yüncü

arXiv · 2502.04941

Detection efficiency and spatial resolution of Monolithic Active Pixel Sensors bent to different radii

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Abstract

Bent monolithic active pixel sensors are the basis for the planned fully cylindrical ultra low material budget tracking detector ITS3 of the ALICE experiment. This paper presents results from testbeam campaigns using high-energy particles to verify the performance of 50 um thick bent ALPIDE chips in terms of efficiency and spatial resolution. The sensors were bent to radii of 18, 24 and 30 mm, slightly smaller than the foreseen bending radii of the future ALICE ITS3 layers. An efficiency larger than $99.9\%$ and a spatial resolution of approximately 5 um, in line with the nominal operation of flat ALPIDE sensors, is obtained at nominal operating conditions. These values are found to be independent of the bending radius and thus constitute an additional milestone in the demonstration of the feasibility of the planned ITS3 detector. In addition, a special geometry in which the beam particles graze the chip and traverse it laterally over distances of up to 3 mm is investigated.

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Anton Andronic, Pascal Becht, Mihail Bogdan Blidaru, Giuseppe Eugenio Bruno, Francesca Carnesecchi, Emma Chizzali, Domenico Colella, Manuel Colocci, Giacomo Contin, Laura Fabbietti, Roman Gernhäuser, Hartmut Hillemanns, Nicolo Jacazio, Alexander Philipp Kalweit, Alex Kluge, Artem Kotliarov, Filip Křížek, Lukas Lautner, Magnus Mager, Paolo Martinengo, Silvia Masciocchi, Marius Wilm Menzel, Alice Mulliri, Felix Reidt, Riccardo Ricci, Roberto Russo, David Schledewitz, Gilda Scioli, Serhiy Senyukov, Sabyasachi Siddhanta, Jory Sonneveld, Johanna Stachel, Miljenko Šuljić, Nicolas Tiltmann, Arianna Grisel Torres Ramos, Berkin Ulukutlu, Gianluca Usai, Jacob Bastiaan Van Beelen, Yitao Wu, Alperen Yüncü. 2025-02-07. Detection efficiency and spatial resolution of Monolithic Active Pixel Sensors bent to different radii. https://arxiv.org/abs/2502.04941

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