1. HOW TO EXPAND THE PHYSICS REACH WHILE SAVING MONEY FAST-TRACK COLLABORATION Start at Pisa in 1999, funded by Gruppo V: INFN, Dip. Fisica, Dip. Ing. Informatica, SNS - Pisa: A. Annovi, R. Carosi, M. Dell’Orso, P. Giannetti, G. Iannaccone, G. Punzi Offline-quality tracks @LHC Level 1 output rate Joined in 2002: INFN, Dip. Fisica, Dip. Ing. Informatica, SNS - Pisa: P. Catastini, V. Cavasinni, V. Flaminio, T. Del Prete, C. Roda, G. Usai, I. Vivarelli INFN, Dip. Fisica Roma: S. Giagu, M. Rescigno, L. Zanello University of Chicago: M. Shochet Interested to join: University of Geneva: X. Wu Argonne National Laboratory: J. Proudfoot Co-operating on software algorithms: INFN-Dip. Fisica - Genova: F. Parodi Co-operating on standard cell chip: Dip. Fisica - Ferrara: R. Tripiccione P. Giannetti CSN1 3/2/2003 SVT Collaborators

2. Fast-Track Offline-quality tracks made available to LHC L2 triggers, @L1 output rate. Outline: Fitting FTK in the DAQ Working principles Physics reach and trigger strategies QCD multi-jet background Size and performance

3. Full resolution hits Low resolution super bins Tracking in 2 steps: find Roads, then find Tracks inside Roads Road Super Bin Road = Pattern Road

4. PIPELINE LVL1 Fast Track + (Road Finder) Fast Track + (Road Finder) EVENT BUILDER CPU FARM CALO MUON TRACKER Buffer Memory ROD Buffer Memory ROB offline quality Tracks: Pt >1 GeV Ev/sec = 50~100 kHz L2 Algorithms few CPUs FE

5. CMS inner detector 1000 tracks |  |< 2.5 Reconstructed tracks P t > 2.0 GeV     30 minimum bias events + H->ZZ->4  Htt events: 1000 tracks in barrel 120 tracks P t > 2.0 GeV

6. Dedicated device - maximum parallelism: Each pattern with private comparator Road search during detector readout The Event... The Pattern Bank TRACKING WITHPATTERN MATCHING AM the Associative Memory Bingo scorecard

7. ASSOCIATIVE MEMORY: CHIP ARCHITECTURE

8. 1/4  AM Divide into  sectors 6 buses Pixels barrelSCT barrelPixels disks Barrel + Disks to build full  coverage

9. AM input bandwidth = 40 MHz cluster/bus AM input buses = 6 cluster rate Pix 01300 64 MHz Pix 2 + extra1200 57 MHz SC0 + extra 980 49 MHz SC1 + extra1000 52 MHz SC2 + extra 980 49 MHz SC3 + extra 980 49 MHz Ev/sec 50KHz 2 AM partitions for the whole Pix+Si tracker More partitions as a backup option Less partitions Less hardware conservative estimates from inner-detector & pixel TDRs

10. 20 9U VME boards – 3 types SUPER BINS DATA ORGANIZER ROADS ROADS + HITS EVENT # N PIPELINED AM HITS FASTRACK BUFFER MEMORY BUFFER MEMORY Front End Tracker DO-board EVENT # 1 AM-board 50~100 KHz event rate GB Few CPUs Offline quality Track parameters

11. The AM board

12. Track confined to a road, fit is simple Linear expansion in the hit positions x i : –   =  k (c ik x i ) 2  final cut –d = d 0 +a i x i  =  0 + b i x i P t = … Fit reduces to a few scalar products  fast Constants from detector geometry –Calculate in advance –Correction of mechanical alignments via linear algorithm fast and stable A tough problem made easy !

13. Test of the linear fit using a fast simulation of the ATLAS Silicon Tracker Genova group: M. Cervetto, P. Morettini, F. Parodi, C. Schiavi, presented on 20-Nov-2002 at PESA  (d 0 ) = 17  m Track parameter residulas Track parameters: fit value vs. true   /N

14. Z bb bbH/A bbbb tt qqqq-bb ttH qqqq-bbbb H/A tt qqqq-bb H hh bbbb H +- tb qqbb Offline-quality b-tagging: Hadronic or soft-lepton events reach of b’s ATLAS with pixel only b-tag @LVL2 is less efficient with FASTRACK offline b-tag performances @LVL2 ATL-DAQ-2000-033 ATLAS TP 31/3/2000 0.6 100 10 1000 bb RuRu

15. ATLAS: Staging of Trigger/DAQ system -- Deferrals limit mainly available networking and computing for HLT -- Large uncertainties on LVL1 affordable rate vs money (component cost, software performance, etc.) No room for safety factor LVL1 LVL1 rate LVL1 rate HLT HLT selections (kHz) (kHz) selections Rate (examples …) L= 1 x 10 33 L= 2 x 10 33 (Hz) no deferrals extrem deferral (2/3 of CORE) MU6,8,20 230.8  20  2MU6 ---0.2 2  10 ~40 EM20i,25,30 11 4.4 e25i  2EM15i,15,20 2 1 2e15i ~40  60i  2  20i ~40 J180,200,200 0.2 0.2 j400  3J75,90,90 0.2 0.2 3j165  4J55,65,65 0.20.2 4j110 ~25 J50+xE50,60,60 0.40.4 j70+xE70 ~20 Tau20,25,25+xE30 22  35+xE45 ~5 MU10+EM15i --- 0.1 Others 55 others ~30 (pre-scaled, etc.) Total ~ 44 ~ 15 ~200 From Fabiola Gianotti, LHCC, 01/07/2002

16. CMS: Trigger Table @ 2x10 33 cm -2 s -1 Trigger Level-1 HLT Thresh. RateThresh.Rate (GeV) (kHz)(GeV)(Hz) Inclusive iso e 29  2933 Inclusive iso  29 3.380 4 Di-e  17  17 1 Di-  17 1.3 40,25 5 Inclusive iso  14 2.71925 Di-  3 0.9 7 4 Inclusive  -jet 86 2.286 3 Di-  -jet 59 1.059 1 Jet*E t miss 88*46 2.3 180*123 5 1-, 3-, 4-jets 177,86,70 3.0 657,247,113 9 Inclusive b-jet237 5 e*jet 21*45 0.8 19*45 2 Other 0.9 10 TOTAL 16.0 105 From CMS TDR 6, 15/12/2002

17. ATLAS+FTK: Trigger @ 2x10 33 cm -2 s -1 Level 1  soft  :  + very soft jets:~ 2 kHz  P T >6 GeV jet 1 P T >25 GeV+|  | < 2.5 jet 2 P T >10 GeV+|  | < 2.5  hadron: 3 soft jets:~ 4 kHz hadron: 3 soft jets:~ 4 kHz jet 1 P T >70 GeV+|  | < 2.5 jet 2 P T >50 GeV+|  | < 2.5 jet 3 P T >15 GeV+|  | < 2.5  E T >200 GeV Level 2  M bb 50: 2 b-jets + M bb > 50 GeV  3-b: 3 b-jets 3-b: 3 b-jets M bb 50 on level-1 soft  :~ 160 Hz M bb 50 on level-1 hadron:~ 50 Hz 3-b on level-1 soft  :~ 10 Hz 3-b on level-1 hadron:~ 10 Hz

18. Events Z  b-bbar Important b-jet calibration tool M bb (GeV) Level 1: soft  or hadron Level 2: Mbb50 significances: (soft  ) S/  B  60 (hadron) S/  B  20 CDF Run II (S/  B = 35) Cdf/anal/top/cdfr/4158 Events M bb (GeV) 2fb -1 ATLAS + FTK 20fb -1

19. bbH/A  bbbb Analysis: 4 b-jets |  j | 70, 50, 30, 30 GeV efficiency 10% L1: hadron (70,50,15) efficiency 25% L1: soft-  efficiency 19% L2: 3-b efficiency on hadron sample 18% L2: 3-b efficiency on soft-  sample 8% ATLAS-TDR-15 (1999) Effect of jet P T cuts is even worse with deferrals M A (Gev) tan  200

20. Pythia vs CDF RUN I data Physics background Pythia Xsec studysampleData Xsec pp bb  bbbb4 bjet+X 30 pp VH bbqq2bjet+2jet 10 tt bbqqqq2bjet+4jet 15 Multijet QCD background Shower Monte Carlos expected to underestimate data cross-sections. IN CDF WE OBSERVE THE OPPOSITE ? We are studying this background: Different Monte Carlos: 1) Herwig vs Pythia 2) matrix element calculations vs shower Monte Carlos

21. Hqq+HV  10 pb  6 + hadron  0.1 pb on tape  2000 H/year Hbb+Htt  1 pb  6 + hadron  0.05 pb on tape  1000 H/year gg  H  30 pb  6  1 pb on tape  20000 H/year  bb  bb   qq  bbbbqqqq  bbqq  bb  bbbb bbH/A  bbbb CDF ATLAS

22. More examples qqH, VH  bb+njets L1: hadron L2: Mbb50 qqHWHttHZ0HZ0H Efficiency %~25 ~ 90~35 ttH  bbbb+njets, H+Z0  bb+bb L1: hadron L2: 3-b

23. Electron Identification Swapping trigger algorithms can reduce the trigger rate while increasing efficiency! The sooner offline quality tracks are included in the trigger the greater is the final efficiency. CERN/LHCC/2000-17 The efficiency & jet rejection could be enhanced by using tracks before calorimeters. With FTK tracks are ready on the shelf: using tracks is even faster than using calorimeter raw data!

24. 0.4 0.5 0.6 0.7 0.8 0.9 1. 0 0.02 0.06 0.1 0.14  (QCD 50-170 GeV)  (H(200,500 GeV)   1,3h+X) L=2x10 33 cm -2 sec -1 m H =500 m H =200 TRK tau on first calo jets Pix tau on first calo jet Staged-Pix tau on first calo jet 0.007 0.004 TRK tau on both calo jets Calo+TRK:  (QCD)=10 -3  (m H =500)=0.49  (m H =200)=0.45 T=170 ms Calo+PXL:  (QCD)=10 -3  (m H =500)=0.42  (m H =200)=0.41 T=59 ms HLT  selection @ CMS H(200,500 GeV)   1,3h ± + X) CERN/LHCC 02-26 CMS TDR 6 December 15, 2002 Calo tau on first jet

25. Thin Road Width:pix 1mm x 6.5cm Si 3mm x 12.5cm Medium Road Width:pix 2mm x 6.5cm Si 5mm x 12.5cm Large Road Width:pix 5mm x 6.4cm Si 10mm x 12.5cm ATLAS Barrel (~CERN/LHCC97-16) 7 layers: 3 Pixel + 4 micro-strip (no stereo) Cylindrical Luminosity Region: R = 1mm,  z = ±15cm Generate tracks (Pt>1 GeV) & store NEW patterns 10M patterns

26. ATLAS configuration: 12 detector layers – 5 10 5 SB/layer 128 chips/board PQ208 die: 16.3 2 mm 2 What chips do we have now ? Config.TechnologyStatusDensity (patt/chip) CDFold full customon-line128 CDFold FPGAworking64 CDFcurrent FPGAdesigned1000 ~ATLASold FPGAunder test32 ATLASstand. cell 0.18estimate (now) 11000 ATLASstand. cell 0.1estimate (1999) 40000 International Technology Roadmap for Semiconductor 1998 2005:patt / 9U-board XCS40XL (.13  ) 64x10 3 Virtex (.1  ) 330x10 3 Stand. Cell (.1  )5000x10 3

27. AM-B1 AM-B0 DO5 DO4 DO3DO2DO1DO0 CUSTOM BACKPLANE FOR SBS & ROADS IN THE PIPELINE ROAD BUS on P2 Ghost Buster DO - DAQ CONNECTION The FTK CRATE CPU0 CPU1 1/2  Barrel + Disks 30M patterns AM-B2AM-B3 CPU2CPU3 { AM-B4AM-B5

28. Standalone program to produce hits from tracks, it includes: multiple scattering ionization energy losses detector inefficiencies resolution smearing primary vertex smearing:  xy =1mm  z =6cm Detector hits generated from (Pythia): QCD10 sample: QCD Pt>10 GeV QCD40 sample: QCD Pt>40 GeV QCD100 sample: QCD Pt>100 GeV QCD200 sample : QCD Pt>200 GeV all samples + noise +. Road finding 6 layers/7 (FTK simulation)

29. Full resolution hits Low resolution super bins Tracking in 2 steps: find Roads, then find Tracks inside Roads Road Super Bin Road = Pattern Road

30. Nfits   x  13 comb x 34 roads = ~440 comb/track 1.4 comb x 4 roads = 6 comb/track QCD Pt10 2.3 comb x 6 roads = 14 comb/track QCD Pt40 7.8 comb x 9.5 roads = 74 comb/track QCD Pt100 27 comb x 25 roads = 658 comb/track QCD Pt200 thin large

31. Pt 200 Pt 100 Pt 40 Pt 10 Step 2: Software Linear Fit Ncomb /trk 658 74 14 6 Ntrk /ev 17 16 10 8 L1 Trig jet soft jet soft  L1 Rate 200Hz <2KHz ~5KHz ~20KHz Fits/sec 2.2MHz <3MHz 750kHz 1.5MHz <8MHz Full 3D fit fit/s 0.6 MHz 2D Fit fit/s 2.2 MHz PIII 800MHz 2.5D Fit fit/s 1.1 MHz Htt 4400 fit/ev = 1ms max latency = 100ms Pt 200 11200 fit/ev. = 3ms only 8 CPUs (barrel) Latency Test Nfit /ev 11186 1184 140 48

32. FTK finds roads with event rates up to 100 KHz. FTK data organization/reduction allows full resolution track fitting with P t >~1 GeV with low CPU usage. More efficient LVL2 triggers: Lower LVL1 & LVL2 thresholds and CPU power saved! FTK is very compact:  2 crates + connection to experiment b-jet tagging at rates 10-20 KHz: more Higgs physics ! FTK as a possible strategy for hadron collider triggers: offline-quality tracks at LVL2

33. Backup slides

34. SVT TDR ’96 Impact parameter SVT simulated on real data superimposed to real offline SVT just started Real data CDF run 127844 No alignment corrections  ~ 45  m  ~ 48  m

35. Independent Tests of QCD Production Channels Direct production Flavor excitation Gluon splitting CDF ok LEP ok CDF ? not ok ? LEP not applic. CDF ? not ok ? LEP F.S.R. only Init. State Rad.75% Fin. State Rad.25% Phys. Rev. D 50, 5562 (1994)

36. CDF: Pythia compared to Herwig 6 pb/GeV 30 pb/GeV Pythia Herwig Direct production g - splitting Flavor excitation Only Direct production doesn’t show differences! Pythia is well tested at LEP, but only Direct Production can be well tested at LEP!

37. 6jet of which 2b-jet  P T >250 GeV: Pythia & Herwig Direct production is negligible PythiaHerwig

38. D ,D s  D 0  D 0  KK BD0BD0 B  hh BsDs*BsDs*

39. The natural implementation of the linear fit is coupled with hits selection made by dedicated hardware (Pisa group proposal). But could be also an important tool for the online software selection. The importance of the size of (assumed) linearity region has been studied in the cases: –Large region (  0 <  /6, |  |<0.5, |z 0 |<10cm): the detector geometry gives the dominant contribution to track resolution (  (d 0 ) = 90  m). –Smallest region (each possible pattern of modules has different tuning): good results (  (d 0 ) = 17  m), but big effort is requested to tune all the detector. The memory needed in this case could be large: N possible patterns X 95 tuning constants (considering six layers) X 4 bytes (variables in float precision). Conclusions (by M.Cervetto on linear fit)

40. Calorimet. LVL2 algorithm for Tau selection Efficiency for H  vs. output rate CMS-IN 2000-033 Tau Identification

41. 0.4 0.5 0.6 0.7 0.8 0.9 1. 0 0.01-0.04-0.06-0.08-0.1 0.12 0.14 0.16  (QCD 50-170 GeV)  (H(200,500 GeV)   1,3h+X) 0.0070.003 L=10 34 cm -2 sec -1 TRK tau on first calo jets Pix tau on first calo jet Staged-Pix tau on first calo jet TRK tau on both calo jets

42. 0. 0.2 0.4 0.6 0.8 1 0 25 50 75 100 125 150 175 200 Calibrated jet Et Selection efficiency Httbar L=10 33 cm -2 sec -1 1 jet 2 jet 3 jet 4 jet 25% 10 Hz |  |< 2.5 Hadronic Htt selection @ CMS Level 1 Level2: 4 jets Et>50 GeV 1 bjet: 10-15 Hz 50% efficiency

43. Composition of LVL1 soft  sample 26% of the events have no b-quarks inside 74% of the events have at least a b-jet: 13% direct production 27.5% flavor excitation 33.3% g splitting 23% of the events have at least 2 b-jet: 13% direct production 3% flavor excitation 7% g splitting =========================================== no-btagging: mjj>70 GeV Rate=1.2 ± 15% kHz double b-tagging: mbb>70 GeVRate=110 Hz

44. Level 2 rates: Pythia+ATLfast Ideal:  b =100%  c =0%  u,d =0% Real:  b =60%  c =10%  u,d =1% Mis-tag:  b =100%  c =10%  u,d =1%

45. ATL-DAQ-99-014 # RODS # RODS 360 O in  180 O in  Pix 036 18 Pix 2 3216 Pixdisk 16 8 SC0-3 4422 SCdisk4824 TOT 176 88

46. Now: CDF-like configuration: 0.45 G bit /s 6 layers - 48000 250  wide SB/Layer full custom (.7  ) - 128 patt/chip - 16x10 3 patt/9U board XCS30XL (.35  )- 128 patt/chip - 16x10 3 patt/9U board XC2S200E (0. 18  6 lay) 50 euro/chip - 300 patt/chip - 38x10 3 patt/9U board XC2V1000 (0.15  8 lay – 0.12  transistors ) - 1200 patt/chip - 153x10 3 patt/9Uboard EP1C20F324C8 (0.13  50 euro/chip - 1100 patt/chip - 141x10 3 patt/9Uboard Stand.Cell (.35  ) - 1000 patt/40 mm 2 Stand.Cell (.18  ) - 4000 patt/40 mm 2 Stand.Cell (.13  ) - 16000 patt/40 mm 2 The Associative Memory CHIP 128 chips/board PQ208 (die:16.3 2 mm 2 )

47. 2005: LHC-like configuration: 4.G bit /s 12 layers - 500000 SB/Layer XCS40XL (.13  )- 64x10 3 patt/9U board Virtex (.1  ) -330x10 3 patt/9U board Stand.Cell (.1  ) - 5x10 6 patt/9U board International Technology Roadmap for Semiconductor 1998 CDF AM = 400 k pat.  4 milioni di pat. XC2S200E  55 $/chip;14000 chips: 1.4 GL XC2V1000  200$/chip; 3500 chips: 1.4 GL Standard Cell  1000 chips; 200 + 200 ML