A micro-TCA based data acquisition system for the Triple-GEM detectors for the upgrade of the CMS forward muon spectrometer

Abstract

We will present the electronic and DAQ system being developed for TripleGEM detectors which will be installed in the CMS muon spectrometer. The microTCA system uses an Advanced Mezzanine Card equipped with an FPGA and the Versatile Link with the GBT chipset to link the front and backend. On the detector an FPGA mezzanine board, the OptoHybrid, has to collect the data from the detector readout chips to transmit them optically to the microTCA boards using the GBT protocol. We will describe the hardware architecture, report on the status of the developments, and present results obtained with the system.In this contribution we will report on the progress of the design of the electronic readout and data acquisition (DAQ) system being developed for Triple-GEM detectors which will be installed in the forward region (1.5 ¡ eta ¡ 2.2) of the CMS muon spectrometer during the 2nd long shutdown of the LHC, planed for the period 2018-2019. The architecture of the Triple-GEM readout system is based on the use of the microTCA standard hosting FPGA-based Advanced Mezzanine Card (AMC) and of the Versatile Link with the GBT chipset to link the front-end electronics to the micro-TCA boards. For the on-detector electronics a new front-end ASIC, called VFAT3, is being developed for the CMS Triple-GEM system. Its architecture is based on the TOTEM VFAT2 chip which is currently used to test the CMS Triple-GEM prototypes and the new data acquisition system. On detector, a Xilinx Virtex-6 FPGA mezzanine board, called the OptoHybrid, has to collect the data from 24 front-end chips and to transmit the data optically to the off-detector micro-TCA electronics as well as to transmit the trigger data at 40 MHz to the CMS Cathode Strip Chamber (CSC) trigger. Two versions of this OptoHybrid have already been designed. They are used to readout the CMS Triple-GEM prototypes equipped with VFAT2 chips and both have been tested with beam at CERN. The microTCA electronics provides the interfaces from the detector (and front-end electronics) to the CMS DAQ, TTC (Timing, Trigger and Control) and Trigger systems. Each micro-TCA crate can house 12 AMC boards. Currently the GLIB board designed by CERN is used for the system developments. For the final system more powerful boards based on the Virtex-7 or Kintex-7 Xilinx FPGA are envisaged. During the LHC yearly extended technical stop of winter [2016][2017]8 Triple-GEM detectors will be installed inside CMS. They will be read-out with the existing VFAT2 chip and with the data acquisition system described above. To prepare this installation, called slice-test, a dedicated test bench has been set-up at CERN to integrate the GEM with the CSC electronics. This work also includes the development of the DAQ software based on xDAQ and of the detector control system.In this contribution we will describe the hardware architecture and expected performance, report on the status of the developments of the various electronic components and present preliminary results obtained with the microTCA-based readout sys...

Development of the CMS detector for the CERN LHC Run 3

“…The opto-hybrid board transmits the data via optical links to the off-chamber backend readout and also sends data to the CSC trigger board for processing at L1. The optical links are routed from the opto-hybrid boards on the chambers to patch panels on the periphery crates and then to off-detector electronics in a 𝜇TCA crate [142]. The backend boards are CTP7 𝜇TCA boards, which are described in ref.…”

Commissioning and performance of the GE1/1 slice test detectors

“…Fig.1 shows the configuration of the chambers installed in CMS: Slot1 contains four GEMINI, i.e. a couple of Triple-GEM detectors, powered through a ceramic divider and * Corresponding author read out with VFAT2 [3] chip and optohybrid v2b [4]. In Slot2 instead, the unique GEMINI is powered through a multichannel power supply and, since January 2018, is read out with the new system based on VFAT3b [5] chip and optohybrid v3 [5].…”

Operational Experience With the GEM Detector Assembly Lines for the CMS Forward Muon Upgrade

“…3) Latency Scan: It shows the amount of recorded events per different latency values, over the total number of events. The latency value is defined as the time difference between the time of arrival of a L1Accept (L1A), i.e., an event accepted by the Level 1 trigger, and the time at which the related event is stored [6]. Figs.…”