Real-time antiproton annihilation vertexing with submicrometer resolution
Michael Berghold, Davide Orsucci, Francesco Guatieri, Sara Alfaro, Marcis Auzins, Benedikt Bergmann, Petr Burian, Roberto Sennen Brusa, Antoine Camper, Ruggero Caravita, Fabrizio Castelli, Giovanni Cerchiari, Roman Jerzy Ciuryło, Ahmad Chehaimi, Giovanni Consolati, Michael Doser, Kamil Eliaszuk, Riley Craig Ferguson, Matthias Germann, Anna Giszczak, Lisa Glöggler, Łukasz Graczykowski, Malgorzata Grosbart, Natali Gusakova, Fredrik Gustafsson, Stefan Haider, Saiva Huck, Christoph Hugenschmidt, Malgorzata Anna Janik, Tymoteusz Henryk Januszek, Grzegorz Kasprowicz, Kamila Kempny, Ghanshyambhai Khatri, Łukasz Kłosowski, Georgy Kornakov, Valts Krumins, Lidia Lappo, Adam Linek, Sebastiano Mariazzi, Pawel Moskal, Dorota Nowicka, Piyush Pandey, Daniel PĘcak, Luca Penasa, Vojtech Petracek, Mariusz Piwiński, Stanislav Pospisil, Luca Povolo, Francesco Prelz, Sadiqali Rangwala, Tassilo Rauschendorfer, Bharat Rawat, Benjamin Rienäcker, Volodymyr Rodin, Ole Rohne, Heidi Sandaker, Sushil Sharma, Petr Smolyanskiy, Tomasz Sowiński, Dariusz Tefelski, Theodoros Vafeiadis, Marco Volponi, Carsten Peter Welsch, Michal Zawada, Jakub Zielinski, Nicola Zurlo, AEgIS Collaboration

abstract
Primary goal of the AEgIS experiment is to precisely measure the free fall of antihydrogen within Earth's gravitational field. To this end, cold(equivalent to 50 K) antihydrogen will traverse a two-grid moiré deflectometer before annihilating onto a position-sensitive detector, which shall determine the vertical position of the annihilation vertex relative to the grids with micrometric accuracy. Here, we introduce a vertexing detector based on a modified mobile camera sensor and experimentally demonstrate that it can measure the position of antiproton annihilations within 0.62(+0.40)(-0.22) micrometer, a 35-fold improvement over the previous state of the art for real-time antiproton vertexing. These methods are directly applicable to antihydrogen. Moreover, the sensitivity to light of the sensor enables in situ calibration of the moiré deflectometer, substantially reducing systematic errors. This sensor emerges as a breakthrough technology toward the AEgIS scientific goals and will constitute the basis for the development of a large-area detector for conducting antihydrogen gravity measurements.