Year: 2026
Type: article
Abstract: The Compressed Baryonic Matter (CBM) Experiment at FAIR aims to investigate strongly interacting matter in a regime of high net-baryon density and moderate temperature using a fixed-target setup. Its Micro Vertex Detector (MVD) employs CMOS Monolithic Active Pixel Sensor (MAPS), called MIMOSIS, to achieve high-precision tracking and vertex reconstruction close to the interaction point. MAPS offer high spatial resolution, a minimal material budget, and tolerance against radiation, which makes them well-suited candidates for vertexing and tracking in the harsh CBM environment. MIMOSIS features 1024 × 504 pixels with a frame time of 5 μ s and a spatial precision of about 5–6 μ m. The sensors are required to withstand a total ionizing dose (TID) of about 5 MRad and Non-Ionizing Energy Loss (NIEL) equivalent fluences of approximately 7 × 1 0 13 n eq /cm 2 per year of CBM operation. Various prototypes have been developed through a joint R&D effort by IPHC Strasbourg, Goethe University Frankfurt and GSI Darmstadt. This contribution presents the MVD detector concept and results from radiation-tolerance measurements performed on MIMOSIS sensors. We demonstrate that AC-coupled p-stop pixel variant sustains efficiency above 99% and spatial precision of 5–6 μ m up to the combined target dose of CBM (10 14 n eq /cm 2 + 5 MRad), with the 50 μ m-thick epitaxial variant offering a wider operational threshold margin. As the 50- μ m epitaxial is not a production-standard wafer option, the 25 μ m-thick epitaxial p-stop variant is being considered for the pre-production of the MVD, which equally meets the CBM requirement.
Authors: Ajit Kumar, Ali-Murteza Altingun, Julio Andary, Benedict Arnoldi-Meadows, Jerome Baudot, Gregory Bertolone, Auguste Besson, Norbert Bialas, Christopher Braun, Roma Bugiel, Gilles Claus, Claude Colledani, Hasan Darwish, Michael Deveaux, Andrei Dorokhov, Guy Dozière, Ziad El Bitar, Ingo Fröhlich, Mathieu Goffe, Benedikt Gutsche, Abdelkader Himmi, Christine Hu-Guo, Kimmo Jaaskelainen, Oliver Keller, Michal Koziel, Franz Matejcek, Jan Michel, Frederic Morel, Christian Müntz, Hung Pham, Christian Joachim Schmidt, Stefan Schreiber, Matthieu Specht, Joachim Stroth, Eva-dhidho Taka, Isabelle Valin, Roland Weirich, Marc Winter, Yüe Zhao
Institutions: Goethe University Frankfurt, European Spallation Source, Centre National de la Recherche Scientifique, Institut Pluridisciplinaire Hubert Curien, Université de Strasbourg, GSI Helmholtz Centre for Heavy Ion Research, Facility for Antiproton and Ion Research, Université Paris-Saclay, Institut National de Physique Nucléaire et de Physique des Particules, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,620
Funder: Deutsches Elektronen-Synchrotron
OpenAlex ID: W7204917546