P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 1 New CMS Level-1 Trigger Design for the Upcoming Data Taking Pamela Klabbers for the CMS Collaboration Physics Department, University of Wisconsin, Madison, WI, USA IRPD13 Wednesday, 9 October 2013

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 2 Large Hadron Collider (LHC) Run 2 LHC is currently improving the magnet interconnections so that we may safely go to proton energies of 6.5 TeV Minimum 13 TeV p-p center of mass energies Second LHC run possibly another discovery run Additional increase in luminosity 4-8 times previous run 25* or 50 ns bunch spacing LHC will exceed the original design luminosity (~20 ev/crossing) A challenge to separate the interesting event from low-energy background (Pile-Up)  ~ original design luminosity Heavy Ions expect lumi increase of 4-8 times previous

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 3 CMS Triggering Challenges Original specification for CMS detector electronics was to operate at a trigger rate of up to 100 kHz Some CMS detector systems would need replacement or major upgrades to exceed this rate (e.g. tracker replacement) Increases in energy, luminosity, and pile-up require significantly higher thresholds to operate with the current L1 trigger Need to maintain our sensitivity for electroweak physics and TeV scale searches Maintain same acceptances as running Solution is to upgrade the trigger to Improve resolution Improve efficiency Reduce trigger rates Commission in parallel to existing trigger Reduce the risks associated with commissioning a new system Validate performance, seamless switch-over when ready

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 4 L1 Trigger Upgrade Goals Improve e/  object isolation using calorimeter energy distributions with Pile-Up (PU) subtraction Improve jet finding with PU subtraction Improve hadronic  ID with a smaller fiducial area Improve muon p T resolution Isolate muons  using calorimeter energy distributions with PU subtraction Improve global Level-1 trigger menu Allow greater number of triggers Allow more sophisticated algorithms Simplify the hardware to reduce costs and maintenance requirements Use similar electronics as in other CMS upgrades

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 5 Hardware Upgrades Use Modern High-Capacity FPGAs with high speed links 10x increase in comparison to those currently operating in CMS Take advantage of modern  TCA technology Standardized hardware platform (specs at: Hot swappable, inexpensive modules, very configurable Point to point high-speed-serial instead of parallel VME Significantly more backplane bandwidth Not including spare I/O Native support for several protocols GbE, Serial ATA, Serial Attached SCSI, PCIe, and Serial Rapid IO Redundant Power Supplies,  TCA Carrier Hubs (MCHs), and cooling units CMS will use the 2 nd MCH slot for DAQ and timing and trigger signal distribution (custom AMC13*) Smaller form factor cards New Custom Interface to Data Acquisition (DAQ) and Trigger Timing and Control (TTC) system AMC13* (Advanced Mezzanine Card) *For more details go to

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 6 Original CMS Level-1 Trigger Calorimeter, muon, and beam monitoring (not shown) systems participate in CMS L1 0.9<|  |<2.4 4  4+4  4  e, J, E T, H T, E T miss L1A 40 MHz pipeline Calorimeter Trigger ECAL Trigger Primitive s ECAL Trigger Primitive s HCAL/HF Trigger Primitive s HCAL/HF Trigger Primitive s Regional Calorimeter Trigger Regional Calorimeter Trigger Global Calorimeter Trigger Global Calorimeter Trigger Muon Trigger RPC hits CSC hits DT hits Segment finder Track finder Track finder Pattern Comparator Pattern Comparator Segment finder Track finder Track finder Global Muon Trigger Global Trigger TTC system TTS system Detector Frontend Status Link system 32 partitions CMS experiment 0<|  |<5 |  |<3 |  |<1.2|  |<1.6

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 7 Muon Geometry 2015

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 8 Muon Trigger Upgrade Currently 3 different track finders (DT, RPC, CSC) Send 16 muon candidates to Global Muon Trigger Lateral exchange of information CSC Muon Port Card (MPC) has a bottleneck - max 3 track seg. to track finder Upgrade New CSC MPC FPGA (on mezz) – send all 18 possible track segments More CSCs and RPCs on Endcap (1.25 < |  | < 1.8) Upgrade to |  |>2.1 CSC electronics Split chamber hits before track finders Combine in one track finder,  TF Better overlap, more tolerant of dead channels Fewer fake muons No lateral exchange of information Include calo trigger info for  -isolation More, higher-resolution muons at Global Trigger for improved isolation, invariant mass, etc.

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 9 Muon Hardware Large modular LUT processor MTF7 Being built for Muon Endcap upgrade but designed to be compatible with other muon TFs To be used in overlap region Maximizes input from muon detectors Large capacity for RAM (~1GB) for track-finding Prototype with Virtex 6 Virtex 7 design in progress Optical Module Core Module

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 10 CMS Calorimeter Geometry EB, EE, HB, HE map to 18 RCT crates Provide e/  and jet,  E T triggers

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 11 Calorimeter Trigger Commissioning in Parallel ECAL – Upgrade link mezzanine from Cu to Optical (oSLB) HCAL – Passively split Front-End input to Back-End (BE), keep existing BE and upgrade to new optical BE in parallel HF – Upgrade all BE electronics for 2015 will have higher granularity for trigger RCT – Upgrade half of Recv. Mezz. to optical (oRM) for ECAL and HF Architecture choice – Time multiplexed or conventional pipelined Time multiplexed chosen All calorimeter data flows through one FPGA at full granularity Potentially more flexible Demonstrated with prototype cards Hardware can implement either trigger architecture choice

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 12 Calorimeter Hardware Layer-1 CTP6 (left), oSLB & oRM (center), and Layer-2 MP7 (right) CTP6 – Dual Virtex 6 (XC6VHX250T) FPGAs, 48 optical inputs, 12 outputs Virtex 6 limits link speed to 6.4 Gb/s (validated), new CTP7 with Virtex 7 allows 10 Gb/s For CTP7: Zynq processor running Xilinx PetaLinux for service tasks oSLB and oRM Mezzanine work on existing hardware – Kintex 7 FPGA Links validated to 4.8 Gb/s MP7 – Single Virtex 7 FPGA, up to 72 input & output links dep. on Virtex 7 part Links validated at 10 Gb/s Extensive Firmware and Software development Latest version of MP7 with XC7VX690T uses all 72 input and output links MMCPower Supplies BE FPGA FE FPGA Avago Rx Avago Tx Dual SDRAM For DAQ & TCP/IP JTAG USB Interface Rx Tx Rx Tx FPGA 1V0 2xQDR (Bottom) 2V5 3V3 1V5 1V8  SD USB  C (Bottom) oRM oSLB

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 13 Global Trigger Remove current 128 algorithm limit Most of the 128 algos were used in 2012 Receive more objects Increase over current 12 jets, 8 electrons, 8 muons, and global quantities Higher resolution with increased logic More sophisticated correlations, e.g. invariant mass calculations Trigger Control System merges with Trigger Timing and Control System Utilize MP7 calorimeter processor card FW and SW development already under way with Virtex 6 based card L1 Calorimeter Trigger L1 Muon Trigger Technical Triggers GLOBAL TRIGGER PROCESSOR Trigger Control System TTC System Detector Front-Ends Present Global Trigger

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 14 Trigger Control and Distribution System TCDS provides clock and triggers to CMS detectors and sends and receives control signals Slows or stops triggers if detector buffers are full or there are errors New system allows for more slices of detector to run in parallel, helping the (re)commissioning of CMS Installation during mid 2014 as part of the DAQ upgrade

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 15 Expected Performance: Muons Barrel Endcap 2012 High Pileup Data (~66 ev/crossing) Tail clip: after p T lookup, candidates sent back to FPGA and muons in 5, 10, or 15% tails of distributions demoted to lower p T. Result: Much lower rate for a slight efficiency loss.

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 16 Expected Performance: e/  5x Rate reduction, similar efficiency

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 17 Expected Performance: Taus and Jets Current  algo based on jet trigger with large fiducial area, is useless with high PU Upgrade based on e/  algo with a significantly smaller fiducial area. Jet goes from 12x12 towers square to 8x8 circular and now includes PU subtraction, resulting significant rate reduction for multi-jet triggers Single Tau Quad Jet

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 18 Trigger Menu Sample Menu for Lumi =1.1e34 Significantly reduced lepton thresholds Improved  efficiency with slightly shallower turn-on Improved multi-jet triggers

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 19 Higgs and SUSY Performance Multijet Single e/   & single e/  Higgs SUSY

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 20 SummarySummary This upgrade is currently under way With our new hardware CMS will be able to keep our thresholds and rates low without sacrificing physics! How will this proceed? Until end of 2014* - cards and splitting New Back End for HF Mezzanine cards for ECAL Back-End and Splitting for HCAL Mezzanine cards on existing RCT for HF and ECAL Back-End Mezzanine cards for Endcap Muon Track Finder 2015 – Commissioning in parallel New calorimeter trigger New muon trigger, using slice of DT and full CSC and RPC data 2016 New Trigger ready for 2016 LHC physics run! *end of Long Shutdown 1, currently under way

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 21 BackupBackup Reference: L1 Trigger Upgrade TDR:

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 22 The Large Hadron Collider

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 23 LHC p-p Collisions Operations 2012: √s = 8 TeV Peak Instantaneous Luminosity: > 7.5e33? 2015: √s = 13 TeV Predicted Peak Instantaneous Luminosity: 3.5 TeV Beam Energy 2808 Bunches/Beam (25 ns) Protons/Bunch cm -2 s -1 Max Inst Lumi

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 24 CMS Detector * *Actually 3.8 T

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 25 CMS Trigger & DAQ Systems Level-1 Trigger LHC beam crossing rate is 40 MHz & at full Luminosity of cm -2 s -1 yields 10 9 collisions/s Reduce to ~100 kHz output to High Level Trigger and keep high-P T physics Pipelined at 40 MHz for dead time free operation Latency of only 3.2  sec for collection, decision, propagation

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 26 e/  and Jet Algorithms 4x4 Tower sums from RCT to GCT Jet or  E T 12x12 trig. tower  E T sliding in 4x4 steps w/central 4x4 E T > others  : isolated narrow energy deposits Energy spread outside  veto pattern sets veto Jet   if all 9 4x4 region  vetoes off GCT uses tower sums for E T,ME T jets for H T, MH T Electron (Hit Tower + Max) 2-tower  E T + Hit tower H/E Hit tower 2x5-crystal strips >90% of E T in 5x5 (Fine Grain) Isolated Electron (3x3 Tower) Quiet neighbors: all towers pass Fine Grain & H/E One “L” of 5 EM E T < Thr.

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 27 Muon Trigger 3 muon detectors to |  |<2.4 Drift Tubes Track Segment ID and Track Finder Cathode Strip Chambers Track Segment ID and Track Finder Resistive Plate Chambers Pattern Matching 4 candidates per subsystem to Global Muon Trigger Global Muon Trigger sorts, removes duplicates, 4 top candidates to Global Trigger Track building at 40 MHz! In 2015: ME1/1 electronics upgrade New CSC and RPC Chambers 2015

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 28 L1 Trigger Custom Hardware Hundreds of boards Thousands of: ASICs FPGAs Copper Cables Optical Fibers (Wo)man hours Global Muon Trigger & Global Trigger (Vienna) RCT (Wisc.) CSCTF (Florida) DTTF (Vienna) GCT (Imperial) RPC PaC (Warsaw)

P. Klabbers, U. Wisconsin, IRPD13, October 2013 New CMS Level-1 Trigger - 29 Calo Trigger Staging Talk covers final version of calorimeter trigger, Stage 2 CMS will have a Stage 1 intermediate solution to reduce rate and improve algorithms with higher lumi in 2015 Install inexpensive oRSC card in RCT (18 total cards – one per crate) Xilinx Kintex part, multiple optical outputs for GCT and new calo trigger Provide readout of RCT output (VME or via optical connection to new card) Additional processing for current calorimeter trigger HCAL Optical Splitters Regional Calo Trigger Global Calo Trigger Layer 2 Calo Trigger Layer 1 Calo Trigger HCAL Energy HTR ECAL Energy TCC HF Energy  HTR HCAL Energy mHTR Copper Optical EM Candidates Region Energies Entire Summary oSLB oRM oRSC CTP MP7