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arXiv · 2606.01971

Demonstrating CBM Capabilities by $\Lambda$ Baryon Reconstruction in Ni+Ni Collisions with the mCBM Experiment at SIS18 of GSI/FAIR

Abstract

The Compressed Baryonic Matter (CBM) experiment at the upcoming Facility for Antiproton and Ion Research (FAIR) is a high-rate fixed-target experiment designed to investigate nuclear matter at extreme baryon densities in relativistic nucleus-nucleus collisions. To enable high-statistics measurements of rare probes, CBM is designed to operate at event rates up to 10 MHz. This necessitates the development of fast and radiation-tolerant detectors, self-triggered front-end electronics, a free-streaming data acquisition architecture, and real-time event reconstruction capabilities. Prototype versions and pre-series productions of the CBM detector systems have been deployed in the mini-CBM demonstrator setup mCBM - an experimental precursor comprising sub-components of all major CBM systems, installed at the SIS18 facility of GSI/FAIR within the FAIR Phase-0 program. In 2024, Ni+Ni collisions at a kinetic beam energy of 1.93 AGeV and an average interaction rate of about 250 kHz were successfully recorded. This dataset enables a detailed evaluation of the operational performance of the detector systems as well as the complete CBM data chain, while the reconstruction of rare $\Lambda$ baryons serves as a natural benchmark. This paper presents the first results on $\Lambda$ signal reconstruction with the mCBM experiment, demonstrating the readiness of the detector technologies and the data chain for the upcoming full-scale CBM experiment.

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CBM Collaboration, A. Agarwal, Z. Ahammed, N. Ahmad, L. J. Ahrens, M. Al-Turany, N. Alam, J. An, J. Andary, A. Andronic, H. Appelshäuser, B. Arnoldi-Meadows, B. Artur, M. D. Azmi, M. Balzer, A. Bandyopadhyay, V. A. Bâsceanu, J. Becker, A. Belousov, A. Bercuci, R. Berendes, D. Bertini, O. Bertini, M. Beyer, O. Bezshyyko, P. P. Bhaduri, A. Bhasin, M. S. Bhat, S. A. Bhat, T. A. Bhat, W. A. Bhat, B. Bhattacharjee, A. Bhattacharyya, N. K. Bhowmik, S. Biswas, T. Blank, N. Bluhme, C. Blume, D. Bonaventura, J. Brzychczyk, U. Bykova, M. Cãlin, J. Calvo-Lorenzo, A. Chakrabarti, P. Chaloupka, A. Chattopadhyay, So. Chattopadhyay, Su. Chattopadhyay, H. Cherif, S. Chernyshenko, I. Ciepał, E. Clerkin, L. M. Collazo Sánchez, M. Csanád, P. Dahm, A. Daribayeva, D. Das, R. Das, S. Das, J. de Cuveland, D. -A. Deară, H. Deppe, I. Deppner, A. A. Deshmukh, M. Deveaux, V. Dobishuk, A. K. Dubey, A. Dubla, M. Dürr, R. Dvořák, I. Elizarov, D. Emschermann, J. Eschke, L. J. Faber, C. Feier-Riesen, H. Feng, S. Q. Feng, F. Fidorra, C. Fischer, P. Fischer, H. Flemming, H. Floersheimer, J. Förtsch, P. Foka, U. Frankenfeld, V. Friese, I. Fröhlich, F. Frombach, J. Frühauf, T. Galatyuk, G. Gangopadhyay, P. Gasik, C. Ghosh, S. K. Ghosh, D. Gil, S. Gläßel, F. S. Goldenbaum, L. Golinka-Bezshyyko, S. Gorbunov, N. Greve. 2026-06-01. Demonstrating CBM Capabilities by $\Lambda$ Baryon Reconstruction in Ni+Ni Collisions with the mCBM Experiment at SIS18 of GSI/FAIR. https://arxiv.org/abs/2606.01971

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