The Phase-2 Upgrade of the CMS Data Acquisition

21 May 2021, 09:30
30m
Long talk Online Computing Fri AM Plenaries

Speaker

Dr Emilio Meschi (CERN)

Description

The High Luminosity LHC (HL-LHC), will start operating in 2027 after the third Long Shutdown (LS3), and is designed to provide an ultimate instantaneous luminosity of $7.5\times10^{34}$ cm$^{-2}$ s$^{-1}$, at the price of extreme pileup of up to 200 interactions per crossing. The number of overlapping interactions in HL-LHC collisions, their density, and the resulting intense radiation environment, warrant an almost complete upgrade of the CMS detector.
The upgraded CMS detector will be read out by approximately fifty thousand high-speed front-end optical links at an unprecedented data rate of up to 80~Tb/s, for an average expected total event size of approximately $7-10$ MB.
Following the present established design, the CMS trigger and data acquisition system will continue to feature two trigger levels, with only one synchronous hardware-based Level-1 Trigger (L1), consisting of custom electronic boards and operating on dedicated data streams, and a second level, the High Level Trigger (HLT), using software algorithms running asynchronously on standard processors and making use of the full detector data to select events for offline storage and analysis.
The upgraded CMS data acquisition system will collect data fragments for Level-1 accepted events from the detector back-end modules at a rate up to 750 kHz, aggregate fragments corresponding to individual Level-1 accepts into events, and distribute them to the HLT processors where they will be filtered further. Events accepted by the HLT will be stored permanently at a rate of up to 7.5 kHz.
This paper describes the baseline design of the DAQ and HLT systems for the Phase-2 operation of CMS.

Primary authors

Co-authors

Gilbert Badaro (American University of Beirut (LB)) Ulf Behrens (Rice University (US)) James Gordon Branson (Univ. of California San Diego (US)) Philipp Brummer Sergio Cittolin (Univ. of California San Diego (US)) Diego Da Silva Gomes (Universidade do Estado do Rio de Janeiro (BR)) Georgiana Lavinia Darlea (Massachusetts Inst. of Technology (US)) Christian Deldicque (CERN) Marc Dobson (CERN) Dominique Gigi (CERN) Nekija Dzemaili (CERN) Maciej Szymon Gladki (University of Warsaw (PL)) Frank Glege (CERN) Guillelmo Gomez Ceballos Retuerto (Massachusetts Inst. of Technology (US)) Thomas Owen James (CERN) Wei Li (Rice University) Remi Mommsen (Fermi National Accelerator Lab. (US)) Srecko Morovic (Univ. of California San Diego (US)) Dr Luciano Orsini (CERN) Ioannis Papakrivopoulos (National Technical Univ. of Athens (GR)) Christoph Paus (Massachusetts Inst. of Technology (US)) Andrea Petrucci (Univ. of California San Diego (US)) Marco Pieri (Univ. of California San Diego (US)) Ms Ema Puljak (University of Zagreb (HR)) Dinyar Rabady (CERN) Kolyo Raychinov (CERN) Attila Racz (CERN) Hannes Sakulin (CERN) Christoph Schwick (CERN) Dr Dainius Simelevicius (Vilnius University (LT)) Mr Panagiotis Soursos (CERN) Andre Govinda Stahl Leiton (Rice University (US)) Uthayanath Suthakar (CERN) Cristina Vazquez Velez (CERN) Petr Zejdl (CERN)

Presentation materials

Proceedings

Paper