The CBM Micro-Vertex Detector: Toward production readiness with MIMOSIS MAPS
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 (ORCID: https://orcid.org/0000-0002-4346-7335)
- Benedict Arnoldi-Meadows (ORCID: https://orcid.org/0000-0001-9608-6256)
- Roma Bugiel (ORCID: https://orcid.org/0000-0001-8838-8027)
- M. Specht (ORCID: https://orcid.org/0000-0001-6777-042X)
- Franz Matejcek (ORCID: https://orcid.org/0009-0007-3568-1626)
- Oliver Keller (ORCID: https://orcid.org/0000-0002-6592-2984)
- M. Deveaux (ORCID: https://orcid.org/0000-0002-5419-8388)
- C. Müntz (ORCID: https://orcid.org/0000-0001-6978-3136)
- J. Baudot (ORCID: https://orcid.org/0000-0001-5585-0991)
- Ziad El Bitar (ORCID: https://orcid.org/0000-0001-6989-2703)
- Roland Weirich
- Guy Dozière
- G. Bertolone (ORCID: https://orcid.org/0000-0001-9544-7486)
- Yüe Zhao (ORCID: https://orcid.org/0000-0002-9174-0519)
- I. Fröhlich (ORCID: https://orcid.org/0009-0000-6491-853X)
- Julio Andary
- Ali-Murteza Altingun (ORCID: https://orcid.org/0000-0002-9461-4948)
- J. Stroth (ORCID: https://orcid.org/0000-0003-4343-9147)
- G. Claus (ORCID: https://orcid.org/0000-0002-6297-4367)
- B. Gutsche
- N. Bialas
- Michal Koziel
- M. Winter (ORCID: https://orcid.org/0000-0003-4046-9762)
- Jan Michel (ORCID: https://orcid.org/0009-0003-2327-5939)
- C. Colledani
- Isabelle Valin
- Eva-dhidho Taka
- Hasan Darwish
- Hung Pham
- Stefan Schreiber
- Christian Joachim Schmidt
- Abdelkader Himmi
- Andrei Dorokhov
- Kimmo Jaaskelainen
- Frederic Morel
- Christopher Braun
- Mathieu Goffe
- Auguste Besson
- Christine Hu-Guo
Institutions
- Goethe University Frankfurt (DE)
- Centre National de la Recherche Scientifique (FR)
- GSI Helmholtz Centre for Heavy Ion Research (DE)
- Université Paris-Saclay (FR)
- European Spallation Source (SE)
- Scientific Methods (United States) (US)
- Facility for Antiproton and Ion Research (DE)
- Université de Strasbourg (FR)
Publication Details
- Journal
- Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment
- Published
- 2026-09-01
- DOI
- https://doi.org/10.1016/j.nima.2026.171996
- Primary Topic
- Particle Detector Development and Performance
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Deutsches Elektronen-Synchrotron