First physics results with the Silicon Vertex Trigger at CDF-II 2 nd Workshop on the CKM Unitarity triangle. April 5 th -9 th IPPP Durham, England, UK Ivan Vila Instituto de Fisica de Cantabria

April '032I. Vila 2nd CKM Workshop Durham Outline  SVT motivation and overview.  SVT performance.  Charm and B physics with the SVT:  Hadronic triggers  Semileptonic triggers  Summary Related CDF talks: Review on B lifetimes and lifetime differences J. Rademacker Bs mixing results and prospects at CDF/D0 D. Lucchesi Performance of CDF for B Physics R. Oldeman

April '033I. Vila 2nd CKM Workshop Durham B physics at Tevatron  Large b production cross-section   (bb) ~ 100  b E32)   (B+, |y| 6) ~ 3  b E32)  compare:  (bb) ~ 1nb at  (4S) 5E33)  Many B hadrons states produced:  B 0, B +, B s,  b, B c,  b  But… HUGE inelastic cross section ~ 100mb A dedicated trigger needed

April '034I. Vila 2nd CKM Workshop Durham A new tool for selecting B’s  CDF has three dedicated triggers for B/Charm physics  Dimuon  J/     Lepton + track  Semileptonic decays  Two track  Hadronic decays Only available for Run I Implemented by the Silicon Vertex Trigger primary vertex secondary vertex impact parameter ~ 1 mm Silicon microstrip detector included in trigger ! b, c decays

April '035I. Vila 2nd CKM Workshop Durham  Bunch crossing: 396 ns: 2.5 MHz  Level 1: fast programmable logic  Synchronous 5.5  s latency  Calorimeter, Muon, Tracks  Accept rate 15kHz (reduc. ~x200)  SVT trigger paths ~ 40% bandwidth  Level 2: programmable logic + CPU  Asynchronous ~ 20  s latency  Cal cluster, Silicon track  Accept 300 Hz (reduction ~x50)  SVT trigger paths ~ 17 % bandwidth  Level 3: Linux PC farm  ~ Offline quantities  50 Hz (reduction ~ x6)  SVT trigger paths ~ 25% bandwidth Trigger Overview hits d 0,  0, P t SVT SVX II XFT COT hits Tracks  0, Pt d0d0 Beam axis  (1/P T )=1.0%/GeV  (  )=1.5mrad  (d)=35um

April '036I. Vila 2nd CKM Workshop Durham SVT: key techniques  How do we do silicon track reconstruction in about 15 microseconds?  (1) Do everything you can in parallel and in a pipeline.  (2) Pattern recognition:  Database with all patterns corresponding to good tracks  Compare in parallel hits in each event with previous patterns to find track candidates  Bin coordinate information coarsely into roads.  This is done in a custom VLSI chip (Associative Memory).  (3) Linearize the fitting problem.  i.e. solvable with matrix arithmetic

April '037I. Vila 2nd CKM Workshop Durham SVT:Pattern Recognition The AM chip is the physical realization of the template matching pattern recognition algorithm: each AM Chip can compare each hit with all the patterns in memory in parallel, providing the high speed necessary for trigger applications. With the AM, pattern recognition is complete as soon as the last hit of an event is read! Like in a bingo game. Coarser resolution 250  m superstrips 95% coverage each 30 o slice: 2AM boardx128chipsx128roads~ roads Single Hit Superstrip Road 4 Detector Layers XFT info road 1 road z road y

April '038I. Vila 2nd CKM Workshop Durham SVT Performance: precise and fast  IP resolution ~ 50  m  Includes 33  m beam spot  Beam position is computed at real time and subtracted online 24  s Level 1 accept to SVT done 9  s before the first hit is received + ~ 15  s processing time

April '039I. Vila 2nd CKM Workshop Durham SVT Performance:Efficiency  Efficiency evaluated on a sample of J/    Efficiency can still be improved by requiring 4 hits out of the five SVX layers, so far 4 out of 4

April '0310I. Vila 2nd CKM Workshop Durham SVT Performance:Online monitor. Using tracks found at L3 calculate K  invariant mass Excellent online trigger Monitor: The number of D 0 per luminosity unit has to remain constant if detector and trigger are performing well.

April '0311I. Vila 2nd CKM Workshop Durham The Two Track Trigger  2Tracks with: P T >2. GeV, SVT 1 mm > IP >120  m & P T1 +P T2 >5.5 GeV  Collect ~70 pb -1 of Data ~ 0.5M D 0  K  signal  Will have O( 10 7 ) fully reconstructed decays in 2 fb -1 data set !!  Competive, compare FOCUS today’s standard for huge: 139K D0  K-p+, 110K D+  K-p+p+  Charm production cross section measured and compatible SM

April '0312I. Vila 2nd CKM Workshop Durham The Two Track Trigger (2)  Very high purity D 0 signal using “D* tag” technique  D* +  D 0   M(D*)–M(D 0 ):   (M D ) ~ 10 MeV   (  M) ~ 0.6 MeV  20% of the D 0 : D* + tagged  Eliminate the “reflection” background (D 0  K  and  K)  Initial flavor of D 0 is known  D* +  D 0 +  + / D* -  D 0 +  -  The best place to study D 0 mixing and CP violation W/o D* tag with D* tag

April '0313I. Vila 2nd CKM Workshop Durham The Two Track Trigger (and 3)  D s, D +   ;   KK  10 pb -1 of two track trigger  Measure mass difference  99 ± 0.38 ± 0.21 MeV/c 2  PDG: 99.2±0.5 MeV (CLEO2, E691) Before correction + Magnetic field correction + Energy loss correction (dE/dx in the tracking detector)  Momentum scale of the tracking detector is calibrated using the J/     Then extensively tested using K s  , D 0  K ,   , … MM First Run II paper !

April '0314I. Vila 2nd CKM Workshop Durham Lepton + Track Trigger  Lepton + Track : 1  /e p T > 4 GeV +1 other track with p T > 2 GeV, SVT 1mm >IP > 120 mm and M(l-Track) < 5 GeV  Collect ~60 pb -1 of data ~ 0.5M B g lX signal  Lepton + Track dataset (60 pb -1 )  B  l D 0 X (D 0  K  ) : ~ 10K  B  l D* + X (D*  D 0  ): ~ 1.5K  B  l D + X (D +  K  ): ~ 5K  Good signals for calibration  Measure B + and B 0 lifetime  Study B 0 -B 0 mixing

April '0315I. Vila 2nd CKM Workshop Durham Lepton + Track Trigger (2) Lifetime studies ~ 0.07 ps (PDG:0.057 ps) Future: B s mixing (low  m s case) Lifetime studies ~ 0.12 ps (PDG:0.08 ps) Future: semileptonic form factor  B s  l D s X (D s   )   b  l  c X (  c  pK  )

April '0316I. Vila 2nd CKM Workshop Durham Summary  The Silicon Vertex Trigged significant step forward in the quality of fast track finding in hadron collider physics.  A massively parallel/pipelined architecture was used combined with innovative techniques: the associative memory and linearized track fitting  A world plenty of Charm:  Used as benchmark for B two body charmless decays.  The large statistics CDF as world class charm factory.  B fully hadronic and semileptonic decays are under reconstruction  First physics measurements using SVT based samples.  Getting ready for the large luminosity: Bs mixing,  b and B s lifetimes, sin 2b…

April '0317I. Vila 2nd CKM Workshop Durham Back up slices  JUST IN CASE…

April '0318I. Vila 2nd CKM Workshop Durham CDF II Forward Muon Partially New Central Calorimeters Solenoid Old Drift Chamber Silicon Microstrips Tracker Time of Flight Plug Calorimeter New Muon system

April '0319I. Vila 2nd CKM Workshop Durham Tevatron D0 CDF Tevatron Main Injector & Recycler p source L peak : ~1x10 32 s -1 cm -2 Bunch spacing: 396 ns

April '0320I. Vila 2nd CKM Workshop Durham Integrated Luminosity Mar 02 Data used for Today’s results Mar 02 – Jan pb -1 (delivered) 100 pb -1 (to tape) Jet physics: ~ 85 pb -1 B/Charm: ~ 70 pb -1 Jan 03 commissioning Good Run Silicon is off (beam condition)

April '0321I. Vila 2nd CKM Workshop Durham SVT:Track Fitting

April '0322I. Vila 2nd CKM Workshop Durham SVT for B 0       SVT reduces the background rate by a factor of 1000  data recording possible by DAQ SVT 1 MHz 20 Hz 1 Hz 1 kHz picobarns

April '0323I. Vila 2nd CKM Workshop Durham Fake rate

April '0324I. Vila 2nd CKM Workshop Durham Charm Xsec