PreProduction Validation of the ATLAS Level1 Calorimeter Trigger
- Slides: 19
Pre-Production Validation of the ATLAS Level-1 Calorimeter Trigger System ATLAS Level-1 Calorimeter Trigger Collaboration: R. Achenbach 1, C. Ay 2, B. M. Barnett 3, B. Bauss 2, A. Belkin 2, C. Bohm 4, I. P. Brawn 3, A. O. Davis 3, J. Edwards 3, E. Eisenhandler 5, F. Föhlisch 1, C. N. P. Gee 3, C. Geweniger 1, A. R. Gillman 3, P. Hanke 1, S. Hellman 4, A. Hidvégi 4, S. J. Hillier 6, E. -E. Kluge 1, M. Landon 5, K. Mahboubi 1, G. Mahout 6, K. Meier 1, A. Mirea 3, T. H. Moye 6, V. J. O. Perera 3, W. Qian 3, S. Rieke 2, F. Rühr 1, D. P. C. Sankey 3, U. Schäfer 2, K. Schmitt 1, H. -C. Schultz-Coulon 1, S. Silverstein 4, R. J. Staley 6, S. Tapprogge 2, J. P. Thomas 6, T. Trefzger 2, D. Typaldos 6, P. M. Watkins 6, A. Watson 6, G. A. Weber 2, P. Weber 1 1 Kirchhoff-Institut für Physik, University of Heidelberg, Germany für Physik, University of Mainz, Germany 3 CCLRC Rutherford Appleton Laboratory, Oxon, UK 4 Fysikum, University of Stockholm, Sweden 5 Physics Department, Queen Mary, University of London, UK 6 School of Physics and Astronomy, University of Birmingham, UK 2 Institut Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Pre-Production Validation of the ATLAS Level-1 Calorimeter Trigger System o Trigger Architecture o Module Design and Challenges o Testing Methodologies: o o o Software data verification Real-time link stability measurements Test-beam performance Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Level-1 triggering in ATLAS o o Muon Detectors Calorimeter Trigger Muon Trigger All data buffered at bunch-crossing rate of 40 MHz for 2. 5 ms Three-stage triggering system o o Calorimeters Level-1: custom built hardware, fixed latency – target rate 75 k. Hz Level-2: software, Ro. I based selection – target rate 1000 Hz Event Filter: software, full detector – target rate 200 Hz Level-1 has three sub-systems: o o o Calorimeter Trigger Muon Trigger Central Trigger (CTP) e/γ tau jet ET ΣET Central Trigger Processor μ Level-1 Trigger to Front-end Buffers Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier Regions of Interest (Ro. I) To Level-2
Calorimeter Trigger Requirements < 1μs ~2000 Tile Calorimeter Trigger Towers 300 Gbyte/s ~100 bits (0. 5 Gbyte/s) Calorimeter Trigger ~5000 Liquid Argon Calorimeter Trigger Towers Real time (40 MHz) Intermediate data 50 ns Readout System Region of Interest data Level-2 Triggered read out (75 k. Hz) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier Central Trigger
Calorimeter Trigger Architecture Digitized Energies Features: Realtime Path: Fixed Latency Pipelined Calorimeter Signals Many stage processing Dual purpose modules Heavily FPGA based Merging 8 modules Jet/Energy Processor 32 modules Merging 4 modules Preprocessor 124 modules Real-time Data Path Massive parallelism Cluster Processor 56 modules Readout Driver (ROD) 14 modules Readout Data Region of Interest ROD 6 modules Region of Interest Data Five Types of Custom 9 U Modules PPM CPM JEM Merged Results To CTP CMM ROD Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Generic Module Design o Challenges: o o Many FPGAs High connectivity o o o Merging Stage Processing Stage Input Stage 1 -2 FPGA 1 -8 FPGA 1 -20 FPGA Internal External (via backplane) High speed signals Readout output up to 800 Mbit/s Spy Memory Readout Signal Speeds up to: 400 Mbit/s differential 160 Mbit/s single ended Processing… Playback Memory High Density Back-plane Connector (~1150 pins) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
A real example: the Cluster Processing Module Merging Processing o Backplane Connector i/o o Input Stage: o o 8 FPGAs Merging Stage: o o 20 FPGAs Processing Stage: o o Input: ~58 Gbit/s Output: ~28 Gbit/s 2 FPGAs Modules Needed: 56 Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier Input
Module Testing Goals and Tools o High speed link stability and performance o o Use data integrity to establish good timing windows High statistics mode measurements in real-time o o o Algorithm correctness o o Runs in parallel with hardware Predicts output data at any stage Requires generation of synchronised trigger patterns Physics-like Boundary conditions Data formatting o o Detailed Module Simulation Use specially designed test-vectors, eg: o o Parity error counting Dedicated firmware loads Read-out must conform to external expectations System Integration o Does the complete chain work as a trigger? Test-beam operation Analogue inputs vs Calorimeter data Digital processing integrity Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Simulation architecture and usage o o Generic C++ framework VHDL inspired o o o Online Database: Modules present Cabling Configuration Test Vectors Trigger Pattern Processes, Ports, Links Hierarchical, Scalable Output ‘Driven’ Configure hardware (data in playback memories) Run simulation Run hardware Simulation Results Read hardware (spy memories, readout) Compare Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Artificial trigger generation o o o To predict readout data need to control trigger generation Continuous: eg 50 k. Hz ‘Bursty’: eg Bursts of 5 triggers Also need to test hardware with high rate and ‘difficult’ trigger patterns Done via a custom module plus trigger pattern generation (under user control) o Triggers synchronised to playback memories o Simulation also knows about trigger pattern o Many types of pattern possible Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
CPM input LVDS timing windows 20 o o No error in 10 minutes in whole module = bit error rate < 1 in 1013 Error Free Window ~20 ns 1200 Error Count Input FPGA Identifier Input FPGAs receive 40 Mbit/s signals Input strobing requires timing Timing window: 20 ns over whole module Once optimised, check with firmware o 16 Timing structure derived from PCB layout 12 8 800 4 400 0 5 10 15 20 25 0 5 10 Strobe Phase (ns) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier 15 20 Strobe Phase (ns) 25
Processor FPGA timing windows Jet/Energy Processor FPGAs: 385 inputs at 80 MHz 210 on-board, 165 from backplane o Error Free Window ~8 ns Error Count 1600 1200 800 600 800 400 200 0 0 5 Error Free Window ~2. 5 ns 1000 Error Count 2000 Cluster Processor FPGAs: 108 inputs at 160 MHz 60 on-board, 48 from backplane o 10 15 20 Strobe Phase (ns) 25 0 0 5 10 15 20 Strobe Phase (ns) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier 25
ATLAS Combined Test-beam 2004 Hit Merger Jet Processor Cluster Processor Energy Merger Pre-processor 12 Cables: 8 CPM 4 JEM 5 Readout Links Calorimeter Signals: 32 in 8 x 2 x 2 array A full slice through the trigger system o Readout o Triggered successfully for part of the time by L 1 Calo Readout o Ro. I Readout Level-1 Calorimeter Trigger present September to mid-October Readout o ~1% of final capacity Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
The Reality Readout Drivers Cluster/Jet/Energy Processors Pre-processor Receivers Interface to Test-beam Trigger, Timing. . Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Checks on Test Beam data o Internal Consistency checks o o o Assume full granularity input data is correct Are all other data (energies, hits etc) consistent? Performed in ~500, 000 events o o o Only minor problems, identified as firmware features No evidence of data integrity problems Comparisons with Calorimeters o Good correlation was seen o o With some problems – overlapping pulses? Triggers generated on genuine physics events Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Cluster processor hit results 1000 events with no cluster hits just one threshold passed o Four thresholds o 20, 50, 100, 200 Ge. V 100 o Event Count 10 just two thresholds passed three or more thresholds passed o o Hit results are as expected Ro. Is also checked Positions, hits all formed correctly Cluster Energy (Ge. V) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Jet/energy algorithm results Event Count o Event Count 104 103 events with no jet hits Only one threshold used o events with jet hit o o 102 Jet Energy (Ge. V) 170 Ge. V No errors seen in hits No errors seen in energy sums Jet Energy (Ge. V) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Liquid Argon comparison: o o o ~factor 2 scaling (ET) Lose energy in some events: overlapping events? bunch-crossing identification problem? Tile comparison: o o Very encouraging Saturation at ~225 Ge. V understood Hadronic Energy (Ge. V) o Electromagnetic Energy (Ge. V) Correlation with calorimeters 0 50 100 150 200 250 300 350 Trigger Energy (Ge. V) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
Did the Trigger Work? o Run with Cluster Threshold of 20 Ge. V as CTP trigger Clear cut-off in Electromagnetic Energy as Measured by Liquid Argon Detector Trigger Energy (Ge. V) o Jet and Energy Triggers also used in other runs E. M. trigger threshold Calorimeter Energy (Ge. V) Validation of ATLAS Level-1 Calorimeter Trigger, Stephen Hillier
- Coffee cup calorimeter vs bomb calorimeter
- Coffee cup calorimeter vs bomb calorimeter
- Coffee cup calorimeter vs bomb calorimeter
- Speech emergence
- Preproduction costs
- Constant volume calorimeter
- How does a calorimeter work
- Burning a match is what type of energy
- Dhrxn
- Bomb calorimeter equation
- Slug calorimeter
- Hadron calorimeter
- Calorimeter
- Food selma
- Bomb calorimeter uses
- Coffee cup calorimeter equation
- Bomb calorimeter
- Calorimeter
- Calorimeter constant
- Accelerating rate calorimeter