Detector and Run Status: CDF, D

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Detector and Run StatusCDF, DØ and the Tevatron

• Susan Blessing
• Florida State University
• Frontiers in Contemporary Physics II

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The Tevatron

• Run I
• 1.8 TeV
• typically 1.6 x 1031 cm-2 s-1 at the beginning of
  a store during Run Ib
• design luminosity 1 x 1030 cm-2 s-1
• 6 x 6 bunches
• Want more!
• Increase Linac energy
• 200 to 400 GeV
• 1993 for Run Ib
• Replace the Main Ring with the Main Injector
• Antiproton storage ring the Recycler
• Raise the energy to 2 TeV

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Main Ring to Main Injector

• Main Ring
• original proton accelerator
• not designed to be an injector to the Tevatron
• not designed for antiproton production
• in the way of the detectors
• especially DØ!
• no extracted beam during collider operations
• Main Injector
• large aperture, rapid cycling, proton synchrotron
• deliver 120 GeV protons for antiproton production
• accelerate protons and antiprotons to 150 GeV for
  injection
• decelerate 150 GeV antiprotons to 8.9 GeV and
  transfer to Recycler
• deliver 120 GeV protons for MI fixed target
• while stacking antiprotons or more while not
  stacking

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Recycler

• Antiproton availability is the most important
  factor limiting luminosity
• Run I and Run II
• Dont throw the antiprotons away at the end of a
  store!
• 75 of the initial antiprotons are still there
• recover about 60 of these
• The Recycler
• antiproton storage ring
• increase luminosity by 2 over MI alone
• increased stacking rate for antiprotons
• storage of more antiprotons
• re-cool large emittance antiprotons recovered
  from the Tevatron

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Tevatron Engineering Run and Run II Startup

• Protons
• lifetime poor in Tevatron
• Antiprotons
• low intensity
• unstacking blows up emittance by 4x
• 30 in Run I
• non-repeatability when doing transfers
• improve with practice
• 50 loss in Tevatron
• not understood
• Emittances
• large, both transverse and longitudinal

• Tevatron
• at least five weeks of proton-only studies
• Pbar source
• 100 shifts to tune stacking and antiproton
  extraction
• Recycler
• orbit, aperture, beam line, RF, lattice, etc.
  studies
• need antiprotons to commission stochastic cooling
  systems

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Detector Upgrades

• Reduced bunch spacing
• Increased luminosity
• radiation damage to inner detectors

• Lots of data
• Want to do things better
• improved technologies

Tevatron Operations
Run Ib Run II Run IIa Run IIb
Bunches 6 x 6 36 x 36 140 x 103 140 x 103
Protons/bunch 2.3 x 1011 2.7 x 1011 2.7 x 1011 2.7 x 1011
Antiprotons/bunch 5.5 x 1010 3.0 x 1010 4.0 x 1010 1.0 x 1011
Crossing Angle (mrad) 0 0 136 136
Luminosity (cm-2 s-1) 0.16 x 1032 0.86 x 1032 2.1 x 1032 5.2 x 1032
òLdt per week (pb-1) 3.2 17 42 105
Bunch Spacing (ns) 3500 396 132 132
Interactions/crossing 2.5 2.3 1.9 4.8
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CDF Upgrade

• Keep
• 1.4 T superconducting magnet
• central calorimeters
• some of muon system
• New
• microvertex detector
• central tracking system
• endplug calorimeters
• muon coverage
• front-end readout electronics
• data acquisition system

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CDF Silicon Tracking

• Silicon microvertex detector (SVX II)
• five double-sided layers
• barrel geometry
• read out in r-f
• three small-angle and two 90 r-z stereo layers
• Layer 00 (L00)
• located directly on the beam pipe
• r 1.6 cm
• very radiation hard
• Intermediate silicon layers (ISL)
• one full and one partial layer
• allows stand-alone silicon tracking
• for h lt 2
• improves b-tagging efficiency

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CDF Outer Tracking

• Central outer tracker (COT)
• drift chamber
• cylindrical geometry
• near-axial and small angle sense wires
• gold-plated mylar sheets for field shaping
• 3D track reconstruction
• h lt 1.3
• track-based Level 1 trigger
• dE/dx

• Time of flight system
• 216 scintillator bars between COT and solenoid
  cryostat
• 25 ps timing
• particle identification
• p/K/p separation

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CDF Forward Calorimeters

• Old
• gas proportional chambers
• sampling errors, electrical noise, glow
  discharge
• slow charge collection
• separate plug and forward calorimeters
• New
• endplug calorimeters no gap
• scintillator based
• hadronic section
• reuse steel plates, add additional steel to 3
• EM section (new)
• lead absorber

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CDF Muon System

• Central
• lower gas gains
• gaps filled
• Intermediate muon system (IMU)
• in space made available by endplug calorimeters
• coverage to h 2
• Double the central muon coverage of Run I

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CDF Commissioning Run Fall, 2000

• Mostly complete mechanically
• Not quite as complete electronically
• Lots of things to fix, but nothing major

Silicon, COT and calorimeter
Silicon layer 4 known to be noisy No alignment
done yet
Silicon
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CDF Status

• Complete except for
• TOF electronics
• few trigger boards
• silicon detector
• connections and checking
• about another week of connection, cable dressing,
  and testing
• Trigger TDC boards
• 12,000 plated-through holes each
• a few bad ones on each board
• tedious to find!
• possible reliability problem
• enough for COT and most of muon system
• have ordered spares

• Data acquisition
• commissioning run
• all systems have been read out
• Reconstruction software
• all new, C
• works at some level
• reconstructed K0s, Ls, jets from commissioning
  run

K0s
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DØ Upgrade Capabilities

• Tag displaced vertices
• rf resolution lt20 mm
• pT gt 1 GeV, h lt 2
• Reduced muon background

• Momentum measurement
• charge sign
• calorimeter calibration
• Improved electron id
• E/p matching
• forward rejection improved
• factor of 3 5
• Trigger
• Level 1 tracking trigger
• lower muon trigger thresholds without prescaling
• single muon pT gt 7 GeV dimuon pT gt 2 GeV
• displaced vertices
• beyond-the-baseline

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DØ Upgrade

• Keep
• calorimeters
• toroid
• central muon system
• New
• central magnetic field
• central tracking
• forward muon system
• cosmic scintillator shield
• forward shielding
• forward proton detectors

• front-end electronics
• trigger system
• data acquisition system

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DØ Solenoidal Magnet

• 2 T field
• sinq ò Bzdl is uniform to 0.5 along the
  trajectory of any particle reaching the solenoid
• DpT/pT 0.002
• about 1 radiation length thick

• Liquid helium cooling
• Wound with two layers of superconductor
• increased current density at ends for field
  uniformity

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DØ Silicon Microstrip Tracker

• Interleaved barrels and disks
• barrels are a combination of 90 and 2 stereo
  angles
• disks are 15 stereo, 7 in the very forward
  region
• 793,000 channels
• Resolution
• 10 mm in rf 40 mm in z

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DØ Tracking System

• Scintillating fiber tracker (CFT)
• 8 layers, each 2 fiber doublets in a u-z or v-z
  configuration (u,v 3 stereo)
• 20 50 cm from beam
• visible light photon counters
• 77,000 channels

• Preshower detectors (CPS, FPS)
• fast energy and position measurements for trigger
  and id
• lead preradiator
• triangular scintillator strips with embedded
  wavelength-shifting fibers
• read out using VLPCs
• resolution lt1.4 mm for 10 GeV electrons

From cosmic rays
need 2.5 p.e.
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DØ Muon System

• Forward muon system (FAMUS)
• three layers of mini drift tubes
• proportional mode with fast gas
• drift time 60 ns
• three layers of scintillation counters
• Shielding around the beam pipe
• iron (hadron and em absorber)polyethylene
  (neutron absorber)lead (gamma ray absorber)
• Central muon system
• faster gas
• slightly decreased resolution

• Cosmic cap and bottom
• scintillator surrounding detector
• A-phi scintillation counters
• between inner muon PDTs and the toroid

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DØ Forward Proton Detector

• Rapidity gap physics
• Roman pot detectors very close to the beam
• within the beam pipe
• Beyond-the-baseline

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DØ in the Collision Hall
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DØ Detector Status

• Detector is mechanically complete
• except forward proton detector
• Electronics are not
• central fiber tracker and preshower detectors
• readout incomplete
• analog front end at vendor
• very rigorous specs
• May installation for CFT
• end of summer for PS
• silicon microstrip tracker
• about 25 connected
• all parts available
• 6 8 weeks of access

• Current work focusing on the south-west quadrant
  of the detector
• by 1x8 stores, one-quarter to one-half of the
  detector will be functional
• except detectors involving light detection

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DØ Trigger

• Run I 1 MHz to 3.5 Hz
• Run II 7.5 MHz to 50 Hz
• Level 1
• calorimeter, preshower detectors, fiber tracker,
  muon system
• no deadtime at 132 ns running
• 4.2 ms decision time
• pipelined 32 crossings
• 6 kHz output

• Level 2
• multi-detector correlations
• tracking preprocessors
• CFT, FPS and SMT
• 100 ms decision time
• lt 5 deadtime at 132 ns
• 1 kHz output
• Level 3
• parallel, fast processors
• partial event reconstruction
• 100 ms decision time
• depends on the type of event
• 50 70 Hz output

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DØ Trigger Status

• Level 1
• calorimeter and muon
• partly there
• CFT
• prototype boards mid-April?
• Level 2
• a-processors are not available
• preproduction boards perfect
• all first production boards failed
• broken chips, bad plated-through holes,
  non-standard design practices
• some have been repaired
• complete redesign
• off-the-shelf hardware
• prototype this summer

• Level 3
• 8 Hz to start50 Hz mid to end March200 Hz
  May/June1 kHz June/July
• problem with design of serial interface boards
• too ambitious and too big
• used in nearly all L3 components
• simplify design
• component-specific boards
• Start with min-bias triggers

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DØ Computing

• Offline hardware operational
• central analysis cluster
• 192-processor Origin 2000
• SUN database servers
• production and development
• Linux reconstruction farm
• 200 worker nodes
• tape robot
• 750-TB capacity
• Data handling system
• well-tested with simulated data

• Software ready for early running
• all new in C
• full GEANT simulation and digitization
• reconstruction program
• reconstruct jets, EM objects, taus, muons, ET
• verified using simulated data and cosmics
• databases
• in production or under active development
• Level 3 filters
• being verified and ported

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Tentative Schedule
February 28 Establish interlocks
March 1 Tevatron cold ready for beam
March 1 23 Proton only studies
March 24 27 1 x 8 stores
March 28 April 9 Establish 36 x 36 running
April 9 16 36 x 36 stores
April 16 30 Access
May 1 ? Stores, with access4 days of access every two weeks
September One month shutdown
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Run II Has Begun!

• Tevatron
• emittances
• proton lifetime
• antiproton intensity
• tuning and practice
• CDF
• complete silicon cabling
• trigger board testing and installation
• get everything working
• beyond-the-baseline
• complete TOF electronics

• DØ
• complete cabling
• SMT, calorimeters
• CFT, CPS and FPS readout electronics
• all by end of summer?
• Level 2 trigger
• difficult to predict
• goal is to be complete by the end of the
  September shutdown
• beyond-the-baseline
• silicon track trigger
• forward proton detector