The CMS Data Acquisition System for the Phase-2 Upgrade

Jean-Marc André; Ulf Behrens; Andrea Bocci; James Branson; Sergio Cittolin; Diego Da Silva Gomes; Georgiana-Lavinia Darlea; Christian Deldicque; Zeynep Demiragli; Marc Dobson; Nicolas Doualot; Samim Erhan; Jonathan Richard Fulcher; Dominique Gigi; Maciej Gladki; Frank Glege; Guillelmo Gomez-Ceballos; Magnus Hansen; Jeroen Hegeman; André Holzner; Michael Lettrich; Audrius Mecionis; Frans Meijers; Emilio Meschi; Remigius K. Mommsen; Srecko Morovic; Vivian O'Dell; Samuel Johan Orn; Luciano Orsini; Ioannis Papakrivopoulos; Christoph Paus; Andrea Petrucci; Marco Pieri; Dinyar Rabady; Attila Rácz; Valdas Rapsevicius; Thomas Reis; Hannes Sakulin; Christoph Schwick; Dainius Šimelevičius; Mantas Stankevicius; Jan Troska; Cristina Vazquez Velez; Christian Wernet; Petr Zejdl

arXiv · 1806.08975

The CMS Data Acquisition System for the Phase-2 Upgrade

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Abstract

During the third long shutdown of the CERN Large Hadron Collider, the CMS Detector will undergo a major upgrade to prepare for Phase-2 of the CMS physics program, starting around 2026. The upgraded CMS detector will be read out at an unprecedented data rate of up to 50 Tb/s with an event rate of 750 kHz, selected by the level-1 hardware trigger, and an average event size of 7.4 MB. Complete events will be analyzed by the High-Level Trigger (HLT) using software algorithms running on standard processing nodes, potentially augmented with hardware accelerators. Selected events will be stored permanently at a rate of up to 7.5 kHz for offline processing and analysis. This paper presents the baseline design of the DAQ and HLT systems for Phase-2, taking into account the projected evolution of high speed network fabrics for event building and distribution, and the anticipated performance of general purpose CPU. In addition, some opportunities offered by reading out and processing parts of the detector data at the full LHC bunch crossing rate (40 MHz) are discussed.

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Jean-Marc André, Ulf Behrens, Andrea Bocci, James Branson, Sergio Cittolin, Diego Da Silva Gomes, Georgiana-Lavinia Darlea, Christian Deldicque, Zeynep Demiragli, Marc Dobson, Nicolas Doualot, Samim Erhan, Jonathan Richard Fulcher, Dominique Gigi, Maciej Gladki, Frank Glege, Guillelmo Gomez-Ceballos, Magnus Hansen, Jeroen Hegeman, André Holzner, Michael Lettrich, Audrius Mecionis, Frans Meijers, Emilio Meschi, Remigius K. Mommsen, Srecko Morovic, Vivian O'Dell, Samuel Johan Orn, Luciano Orsini, Ioannis Papakrivopoulos, Christoph Paus, Andrea Petrucci, Marco Pieri, Dinyar Rabady, Attila Rácz, Valdas Rapsevicius, Thomas Reis, Hannes Sakulin, Christoph Schwick, Dainius Šimelevičius, Mantas Stankevicius, Jan Troska, Cristina Vazquez Velez, Christian Wernet, Petr Zejdl. 2018-06-23. The CMS Data Acquisition System for the Phase-2 Upgrade. https://arxiv.org/abs/1806.08975

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