1. The DØ Silicon Track Trigger Bill Lee Florida State University 27 October 2003  Introduction + Motivation  Design  Status http://www-d0.fnal.gov/trigger/stt

2. Bill Lee 27 October 2003 2 The DØ Run 2 Detector New state of the art tracker and trigger SMT

3. Bill Lee 27 October 2003 3 Level 1 Central Track Trigger  Custom hardware + firmware  Preprogrammed track equations matched to hit patterns  Sensitive to beam offsets beyond ~1mm from programmed beam spot  Installation complete, Still revising Firmware -

4. Bill Lee 27 October 2003 4 2.3 MHz 2.5 kHz 1 kHz L1 L2 L3 50 Hz Decision time 4.2  s Decision time 100  s Decision time ~50ms p p Crossing frequency 2.3MHz But data acquisition rate is limited to 50 Hz  3 Level Trigger System Hardware based Simple Signatures in each Sub-Detector Software and Firmware based Physics Objects e, ,jets, tracks Software based Simple versions of reconstruction algorithms The DØ Trigger System

5. Bill Lee 27 October 2003 5 The Idea  b quarks are key in many areas:  Higgs Physics (ZH  bb)  top physics ( t->Wb)  B physics  b quarks have a finite lifetime  travel mm’s before they decay   displaced tracks  Would like to trigger on displaced tracks  using the precision of the Silicon Tracker  Impact parameter resolution 35  m (includes 30  m from beamspot) Need to make very fast decisions! Flight Length mm’s Collision Impact Parameter Decay Vertex B Decay Products Tracks - -

6. Bill Lee 27 October 2003 6 Physics Motivation for STT  Increase inclusive bb production yield six-fold with low enough threshold to see Z  bb signal  Control sample for b-jet energy calibration, bb mass resolution, b trigger and tagging efficiencies  Top quark physics  Factor of 2 improvement in top mass systematics due to improved jet energy scale calibration  Heavy bb resonances for Higgs searches  Double trigger efficiency for ZH  ( )(bb) by rejecting QCD gluons and light-quark jets  b-quark physics  Lower p T threshold on single lepton and dilepton triggers (B O  , B s mixing, etc.)  Increase B d o  J/  K S yield by 50% (CP violation)  STT proposed 1998 as addendum to D Ø baseline  Received approval and funding in 1999 - - - - - -

7. Bill Lee 27 October 2003 7 Conceptual Design  L1CTT  tracks in CFT  Define road in SMT  Select SMT hits in roads  Fit trajectory to L1CTT+SMT hits. Measure  pT,  impact parameter,  azimuth  Send results to L2  Pass L1CTT information to L2  Send SMT clusters to L3 road data SMT data Silicon Trigger Card Silicon Trigger Card Silicon Trigger Card Silicon Trigger Card Silicon Trigger Card Fiber Road Card Silicon Trigger Card Track Fit Card L2CTT

8. Bill Lee 27 October 2003 8 STT components  Fiber Road Card  receives and buffers road information from the CFT Level 1 trigger and broadcasts it to other cards  Receives SCL (trigger control) information  Controls buffering for L3 (BC)  Silicon Trigger Cards  find cluster centroids from SMT hits  match centroids to roads from FRC  Track Fit Card  fits tracks using STC clusters and CTT information (2 hits)  Sends track parameters to L2CTT/L2global  2 SMT sectors/crate  6 crates -

9. Bill Lee 27 October 2003 9 TFCSTC FRC STC CPU 12 spare 3 SBC 456791011121314151620 TFC 19181721 spare terminator to L2CTT SCL in to L2CTT 8 spare STC Layout of Run 2A STT Crate 6 Identical Crates with 1 Fiber Road Card 9 Silicon Trigger Cards 2 Track Fit Cards Sector 1 Sector 2 L2 Global STT Design

10. Bill Lee 27 October 2003 10 Contributing Institutions  Boston University  U. Heintz, M. Narain, E. Popkov (PD), L. Sonnenschein (PD), J. Wittlin (PD), K. Black (GS), S. Fatakia (GS), A. Zabi (GS), A. Das (GS), W. Earle (Eng), E. Hazen (Eng), S. Wu (Eng)  Columbia University  H. Evans, G. Steinbrück (PD), T. Bose (GS), A. Qi (Eng)  Florida State University  H. Wahl, H. Prosper, S. Linn, T. Adams, S. Blessing, W. M. Lee (PD), N. Buchanan (PD), S. Tentindo Repond (PD), S. Sengupta (GS), J. Lazoflores (GS), D. Kau (GS), R. Perry (Eng), S. Lolage (GS-Eng), V. Lalam (GS-ENG)  SUNY Stony Brook  J. Hobbs, W. Taylor (PD), H. Dong (GS), C. Pancake (Eng), B. Smart (Eng), J. Wu (Eng)  Manchester University  Michiel Sanders (PD)

11. Bill Lee 27 October 2003 11 FSU contributions to STT  Project leadership:  Horst Wahl (since Sept 1996), project co-leader with Ulrich Heintz (since Aug. 1999)  Beam position issues:  Dan Karmgard, Terry Heuring, Henryk Piekarz, Horst Wahl  Queueing studies:  Sailesh Chopra, Terry Heuring, Brian Connolly, Stephan Linn  Conceptual STT design:  Terry Heuring, Henryk Piekarz, Horst Wahl  Physics studies:  Brian Connolly, Terry Heuring, Harrison Prosper, Horst Wahl  Performance studies:  Terry Heuring, Dan Karmgard, Harrison Prosper, Horst Wahl

12. Bill Lee 27 October 2003 12 FSU contributions to STT, cont’d  generation of look-up tables for hit filter:  Sailesh Chopra, Bill Lee, Jose Lazoflores, Daekwang Kau  design of STC firmware (VHDL) + help with STC design:  Reginald Perry, Shweta Lolage, Vindi Lalam  L1CTT broadcasting:  Brian Connolly, Stephan Linn  STT trigger simulation:  Todd Adams, Brian Connolly, Sailesh Chopra, Harrison Prosper, Silvia Tentindo-Repond, Daekwang Kau, Norm Buchanan  Downloading:  Bill Lee  monitoring:  Sailesh Chopra, Bill Lee, Silvia Tentindo-Repond

13. Bill Lee 27 October 2003 13 FSU contributions to STT, cont’d  STT Examine:  Susan Blessing, Harrison Prosper, Sinjini Sengupta  Procurement of components for STC, motherboards, LTB, LRB  Horst Wahl, Sherry Beasley  Infrastructure at DØ (racks, crates, ethernet connections, CPUs, powersupplies, VTM installation,..)  Bill Lee, Horst Wahl, José Lazoflores  Fake data sender – setting up, programming  Stephan Linn

14. Bill Lee 27 October 2003 14 Downloading and Monitoring  FSU (Bill Lee), with help from BU  STT Crate Initialization  Controlled via Power PC running vxWorks at power-up  Downloads (via C) lookup tables and DSP code and initializes the STT cards to a running state.  Can also be Initialized via Python for test purposes  EPICS STT board support package  Gathers information from cards for monitoring purposes  Runtime downloads via COMICS using trigger initialization parameters  STT Examine  Susan Blessing, Harrison Prosper, Sinjini Sengupta  will be part of triggerExamine package

15. Bill Lee 27 October 2003 15 System Integration  All hardware at hand  Five of six crates fully populated  A seventh crate will be added as a test stand, freeing the sixth crate.  D0 is presently in a shutdown.  Before the shutdown, two STT crates were included in several runs.  Presently able to run at global run rates for several hours.  All five crates can be included in the run at any time  Full track reconstruction  Output to L3 and L2  Coming out of the shutdown, the STT crates should be included in all runs.  Full Commissioning almost complete.

16. Bill Lee 27 October 2003 16 Conclusions  The Silicon Track Trigger is crucial for a large part of the Run 2 physics program.  Higgs, top, B physics  Project almost complete!  All hardware for Run 2a at hand!  Sixth crate commissioned this week.  The STT will be taking data at the end of the shutdown.  FSU group has made and will continue to make substantial contributions to the STT.

17. Bill Lee 27 October 2003 17

18. Bill Lee 27 October 2003 18 Silicon Microstrip Tracker  6 10-cm long barrels + 16 disks  793,000 channels of electronics   SMT hit resolution ~10  m 6 Barrels 12 F-Disks 4 H-Disks

19. Bill Lee 27 October 2003 19 The Central Fiber Tracker  Scintillating Fibers  Up to |  | =1.7  20 cm < r < 51 cm  8 double layers  CFT: 77,000 channels CFT

20. Bill Lee 27 October 2003 20 Motherboard and Communication Links  9Ux400 mm VME64x- compatible  3 33-MHz PCI busses for on- board communications  Data communicated between cards via point-to-point links (LVDS) (Link Transmitter and Receiver Cards)  Control signals sent over backplane using dedicated lines  VME bus used for Level 3 readout and initialization/monitoring Universe II PCI-PCI bridges

21. Bill Lee 27 October 2003 21 Fiber Road Card (FRC) Design  Receives tracks from L1 Central Track Trigger  Communicates with trigger framework via SCL receiver card  Transmits tracks and trigger info to other cards  Manages L3 buffering and readout via Buffer Controller (BC) daughter cards on each motherboard  Implemented in 6 Altera FPGA’s  FLEX 10k30E and 10k50E  30/50 k gates  24/40 k bits of RAM  208/240 pins

22. Bill Lee 27 October 2003 22 FRC Buffer controller Buffer controller Link Receiver Board Link Transmitter Board Fiber Road Card (FRC) Design

23. Bill Lee 27 October 2003 23 Silicon Trigger Card (STC) Design  Performs Silicon clustering and cluster-road matching  Clusters Neighbouring SMT hits (axial and stereo)  Each STC processes 8 silicon inputs simultaneously  Axial clusters are matched to ±1mm-wide roads around each fiber track via precomputed LUT  Mask bad strips and apply pedestal/gain corrections (via LUTs)  Implemented in FPGAs  Main functionality implemented in XILINX VIRTEX XCV812E  ~ 800k gates  1.1 Mbits of RAM  560 pin BGA package  3 PCI interfaces use Altera ACEX EP1K30 chips This project made possible with state- of-the-art FPGAs

24. Bill Lee 27 October 2003 24 Road LUT Road LUT FPGA Silicon Trigger Card (STC) Design

25. Bill Lee 27 October 2003 25 Track Fit Card (TFC) Design  Performs final SMT cluster filtering and track fitting  Receives 2 CFT hits and axial SMT clusters in CFT road  Lookup table used to convert hardware to physical coordinates  Selects clusters closest to road center and performs linearized track fit using precomputed matrix elements stored in on-board LUT  Require hits in only 3 out of 4 silicon layers  Output to L2CTT via Hotlink cards  C code running on 8 DSPs:  TI TMS320C6203B fixed point DSP  300 Mhz  two independent 32-bit I/O busses  performs 16 bit multiply/32 bit add instructions  rated at 2400 MIPS

26. Bill Lee 27 October 2003 26 DSP Hotlink Card Matrix LUT Coordinate Conversion LUT Track Fit Card (TFC) Design