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 μm 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 μm, 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.
Detection efficiency and spatial resolution of Monolithic Active Pixel Sensors bent to different radii / Andronic, Anton; Becht, Pascal; Blidaru, Mihail Bogdan; Bruno, Giuseppe Eugenio; Carnesecchi, Francesca; Chizzali, Emma; Colella, Domenico; Colocci, Manuel; Contin, Giacomo; Fabbietti, Laura; Gernhäuser, Roman; Hillemanns, Hartmut; Jacazio, Nicolo; Kalweit, Alexander Philipp; Kluge, Alex; Kotliarov, Artem; Křížek, Filip; Lautner, Lukas; Mager, Magnus; Martinengo, Paolo; Masciocchi, Silvia; Menzel, Marius Wilm; Mulliri, Alice; Reidt, Felix; Ricci, Riccardo; Russo, Roberto; Schledewitz, David; Scioli, Gilda; Senyukov, Serhiy; Siddhanta, Sabyasachi; Sonneveld, Jory; Stachel, Johanna; Šuljić, Miljenko; Tiltmann, Nicolas; Ramos, Arianna Grisel Torres; Ulukutlu, Berkin; Usai, Gianluca; Beelen, Jacob Bastiaan Van; Wu, Yitao; Yüncü, Alperen. - In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT. - ISSN 0168-9002. - 1083:(2026). [10.1016/j.nima.2025.171131]
Detection efficiency and spatial resolution of Monolithic Active Pixel Sensors bent to different radii
Bruno, Giuseppe Eugenio;Colella, Domenico;Ramos, Arianna Grisel Torres;
2026
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 μm 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 μm, 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
