STAR Upgrade Plans

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STAR Upgrade Plans and RD
Open Meeting on RHIC Planning, December 4, 2003
R. Majka for STAR
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• Physics Questions
• What are the gross properties of the partonic
  matter?
• Is it equilibrated?
• Does it behave collectively?
• What are its early temperature and pressure?
• What is its gluon density?
• Are symmetries restored/broken in the partonic
  matter?
• Spontaneous CP violation
• Chiral symmetry and UA(1) restoration
• What are the properties of the hadronic medium
  after hadronization
• What are the gluon densities in normal nuclear
  matter
• What are the contributions to the nucleon spin?

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• Upgrade Goals
• Keep (expand) STARs large coverage
• Enhanced (higher momentum) PID barrel TOF
• Micro vertex detector and inner tracking for
  enhanced heavy quark ID
• Improved momentum resolution for forward
  (1lthlt2) region - inner and end cap tracking,
• High rate readout and DAQ present large
  samples to high level trigger, also record very
  large samples
• Enhanced Forward instrumentation - hgt2 (Hadron
  calorimetry)
• High rate tracking capability
• High Luminosity, Large pp polarization RHIC
  development and upgrades

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Upgrade

• Physics Bullets
• Determine degree of thermalization and
  collectivity in partonic matter formed in RHIC
  collisions
• Test QCD (for variety of parton types) and
  determine the fate of its fundamental symmetries
  in bulk partonic matter
• Map the contributions of gluons and sea
  antiquarks of different flavor to the spin of the
  proton
• Probe the large gluon densities at low momentum
  fraction in heavy nuclei

TOF Barrel Pixel ?Vertex DAQ/FEE upgrade

RHIC-II

Inner/ endcap tracking
Forward hadron calorimeter
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TOF Correlations, Fluctuations, Partonic
Collectivity, Open Charn, Vector meson (-gtee-),
lepton, di-lepton spectra, away-side jet
fragmentation, exotica searches, LL helicity
correlations, Microvertex Heavy quark
production with identification via slightly
displaced vertices D yields flow to test
degree of thermalization partonic collectivity
c- and b-quark energy loss in partonic
matter. DAQ/FEE Acquisition of very large data
samples for precision and rare process studies
e.g., b-quark jet quenching CP violation search
via ?? spin correlations opposite a high-pT
hadron ?? HBT. Inner/Forward Tracking Upgrade
W production and charge sign discrimination in
polarized pp collisions, especially in endcap
region, for kinematically clean distinction of
flavor-dependence of sea antiquark vs. valence
quark polarizations in proton. Forward Hadron
Calorimeter Jet reconstruction at high
pseudorapidity CGC monojet search in d(p) A
isolation of fragmentation effects in large
single-spin transverse asymmetries in pp ? ?0
production. Robust Tracking in High Luminosity
RHIC II era High luminosity studies of ? - and
heavy-quark tagged jets ?? HBT.
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STAR Detector
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• Ongoing Improvements of STAR Capability

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• STAR Barrel TOF
• MRPC modules to cover outer barrel of STAR TPC
• Dt lt 100 ps
• Large coverage pltfltp, -1lthlt1, R2.1 m
• More than double momentum range of PID (95 of
  charged particles in acceptance)
• 3800 modules with 23,000 readout channels
• Fast detector maintains (improves) trigger
  capability of existing CTB scintilators.

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Multigap Resistive Plate Chamber MRPC
Technology developed at CERN
Read out pad size 3.15cm6.3cm
gap60.22mm 95 C2H2F4 5 Iso-butane
3800 modules, 23,000 readout chan. to cover TPC
barrel
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Examples of Benefit of TOF Open Charm and
Resonances in central Au-Au collisions
FOM (figure of merit) reduction in required
data set by using TOF PID TOF PID also reduces
systematic errors from correlated back-ground due
to misidentified particles
Certain measurements are impossible without TOF
unlike particle correlations (X-p), scale
dependent correlation studies (velocity vs
momentum correlations), exotic searches
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• TOF RD
• Accomplished in FY03
• For RHIC run 3, one full tray installed in STAR
• 28 MRPC modules
• 72 chan. of readout using final FEE components on
  prototype boards connected to CAMAC digitizers
• Signals split to form TOF trigger

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• TOF RD Accomplished in FY03
• SF6 is NOT required in the gas mix
• HV was on for the entire run no failures
• Noise rate 200Hz from OR of 72 chan.
• TPC track matching done (software developed)
• Calibrations (t-zero, slewing, TDC nonlinearity,
  ) are all performed (software developed)
• 85 ps MRPC timing resolution demonstrated for a
  small system in the RHIC/STAR environment
• 95 MRPC efficiency demonstrated in the RHIC/STAR
  environment
• PID capability demonstrated (software developed)
• Electron tagging demonstrated
• Physics publication submitted

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From TOF Triggered Data in d-Au Collisions
p/K separation p1.6GeV/c, p/(Kp) p3GeV/c
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Electron tag from combining TPC dE/dx and TOF
TPC dE/dx for all tracks
TPC dE/dx for tracks with TOF b 1
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• TOF TPC electron Tag
• Works well at low energy complements
  calorimeter
• Gives access to vector meson (r, w, f, J/y) ee-
  decays
• In medium modification, onia studies
• Thermal dileptons
• Single electron spectrum
• D meson yield, flow

Simulations show inner mvertex tracker can
suppress g conversions Do decay electrons follow
Do flow!
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MRPC TOF has run successfully in STAR and
produced publishable physics results.
Nucl-ex/0309012, Sept. 2003 Submitted to PRL
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• TOF RD in 2004
• For the upcoming run (Run 4)
• TOF Tray rebuilt with prototypes of final FEE
  boards
• A few channels of HPTDC digitizers
• Address integration volume issues (space,
  cooling)
• Gain experience with final FEE configuration (24
  channel boards, sealing top of trays
• Gain experience with HPTDC
• Gain running experience with Au-Au collisions
• Continue software development and physics analysis

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• TOF RD in 2004 (cont.)
• For Run 5
• Build a significant amount of full electronics
  chain (up to four trays)
• Build significant number of MRPC modules (up to
  4 trays)
• Operational experience with full electronics
  chain
• Check electronics design for production
• Experience with module production lines
• Finalize module production and QA procedure
• Extended physics capability

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• Proposal for construction is submitted
• Construction funding in FY05
• Construction FY05 FY07
• 30 Trays (25 coverage) in FY06
• Partial (and increasing) coverage (and
  physics capability) available during
  construction phase.

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Micro-Vertex Detector

• High resolution inner vertex detector, better
  than 10 ?m resolution, with better than 20 ?m
  point-back accuracy at the primary vertex.
• CMOS Active Pixel Sensor (APS) technology can
  be very thin, allows some readout to be on same
  chip as detector.
• Develop high speed APS technology for second
  generation silicon replacement (LEPSI/IReS, and
  LBNLUC Irvine)
• Required Areas of development
• APS detector technology
• Mechanical support and cabling for thinned
  silicon
• Thin beam pipe development
• Calibration and position determination
• Data stream interfacing

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• Features of First Generation Design
• 2 layers
• Inner radius 1.8 cm
• Active length 20 cm
• Readout speed 20 ms (generation 1)
• Number of pixels 130 M

• Goals and Milestones
• Choose MIMOSTAR fabrication process, End 03
• Thinned MIMOSA-5 chips to LEPSI/IReS, Feb. 04
• Design of LEPSI/IReS MIMOSTAR chip, May 04
• Tested MIMOSA-5 to LBNL, June 04
• Submit fabrication MIMOSTAR, 2 proto, Sept 04
• First ladder prototype, start Oct. 04
• Tests of 2 MIMOSTAR prototypes, Jan 05
• Final MIMOSTAR prototype design, Mar 05
• Submit fab final MIMOSTAR prototype, Apr 05
• Production tests of final MIMOSTAR proto type
  on wafer, July 05
• Send MIMOSTAR for thinning, Aug 05
• Test thinned and diced MIMOSTAR prototype
  chips, Sept 05
• Mount MIMOSTAR chips on final ladder prototype
• Proposal in 2004

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Mechanical and integration issues are being
addressed
Thin stiff ladder concept
Two Layers of APS
Existing Silicon
Integration volume and rapid insertion/removal
being studied using modern 3-D modeling tools.
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STAR DAQ upgrade DAQ1000

• GOAL increase STARs rate capability to
  equivalent of 1 kHz min-bias AuAu ? 820 MB/s
  instantaneous (300 MB/s time-averaged?)
• IMPLEMENTATION (1) replace TPC FEE with version
  based on ALICE ALTRO chip (2) replace TPC DAQ
  system with one based on storage of only cluster
  information extracted in fast hardware (3)
  upgrade EMC Level 2 Receiver Boards and use for
  other new subsystems as well.
• MILESTONES
• FY04 Run deploy Fast Cluster Finder algorithm
  (? DAQ100) and cluster storage only in software
  as proof-of-principle handle clustered event
  building with 4 Linux-based EVB work stations
• FY04 RD implement a Row Computing Slice (RCS)
  incorporating FCF in hardware (FPGA, DSP, )
  design generic new DAQ Receiver Board prototype
  ALTRO-based FEE
• FY05 Run implement new Receiver Board for
  BEMC/EEMC Level 2 triggering
• FY05 RD design ALTRO ? DAQ interconnect
  prototype DAQ fiber interconnect network system

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Improved Tracking for hgt1
TPC hits only gt 7 hits/track
All hits
Fast Detector hits only
GEM in front of TPC 3-layer Si strip
barrel GEM plane in front of EEMC
18, wrong sign
Pt, GeV/c, reconstructed

• Inner (Si strip) forward (GEM) tracking
  detector concept should eliminate incorrect sign
  reconstructions for W daughters in endcap region!
• Simulated events illuminate endcap region
  uniformly, assume modest fast detector spatial
  resolutions of 100 ?m (GEM) and 50 ?m (Si)

Primary Vertex position, Z, cm
Pt, GeV/c, simulated
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GEM
Gas Electron Multiplier
A micropattern structure produced in 50mm thick
copper clad kapton using lithographic techniques.
55mm holes on 140mm centers Gain up to 103
for single foil
3M Foil (J. Collar) Photo Bo Yu, BNL
CERN Foil (F. Sauli) Photo G. Jesse
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Inner Tracking Forward Tracking

• November 7-8, Meeting at MIT to begin to address
  issues related to integrating requirements and
  design for tracking upgrades
• New working group formed to
• Decide on optimal sequence/staging/integration
  of upgrades and replacement of existing STAR
  subsystems, navigating highly coupled issues
• APS needs fast inner tracker consistent with
  FEE/DAQ upgrade.
• W sign discrimination in endcap region requires
  inner tracker coverage beyond ? 1
• Endcap tracker needs space freed by TPC FEE
  upgrade
• Present SVT FTPC introduce intricate
  mechanical problems for APS insertion/removal
• Mapping onto physics priorities, funding, RHIC
  run plan
• Produce an integrated design addressing these
  issues

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Forward Physics

• Forward Hadron Calorimetry (2.4lthlt4.0, 0ltflt2p)
• Simulations and Design
• Forward jets probing gluon saturation,
  mono-jets
• Is the asymmetry for pions produced in
  transversely polarized proton scattering due to
  spin dependent fragmentation?

Roman Pots (h6.5) Access to a variety of
diffractive phenomena in p-p scattering
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Goals for FY04
TOF Proposal submitted construct 4 prototype
MRPC TOF trays with final on-board time
digitization electronics for installation in STAR
for RHIC run 5 design Level 2 Receiver Board for
TOF other sub-systems. ?Vertex design and
begin fabrication of prototype MIMOSTAR chips
advance mechanical design and begin fabrication
of first prototype APS ladder. Develop
proposal FEE/DAQ build/test several prototype
FEE boards utilizing ALTRO chip. Implement Fast
TPC Cluster Finder algorithm in hardware
contribute to design of new Receiver Board. GEM
(Joint RD with PHENIX) prepare prototype GEM pad
detector and readout electronics for installation
within STAR for RHIC run 5, to test operation and
backgrounds in RHIC collision environment. Build
prototype compact TPC module Inner Endcap
tracking Develop integrated design.
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STAR Future Physics and Planned Upgrades
System RD Constr/Cost
Benefit to STAR

• Barrel MRPC 04 ? 05
  05 ? 06 PID information for 95
• TOF 260k
  4.3M of kaons and
  protons in acc
• 
  2.5M in- kind extended pT for
  resonances
• 
  ?
  v2 Ds ebe correlations
• 
  
  anti-nuclei inclusive
• 
  
  electrons
• Inner ?vtx 04 ? 06
  06 ? 07 Ds , flavor- tagged jets
• (Forward Tracker) 965K
  4M (TBD) (Charge sign for W )
• DAQ Upgrade 04 ? 06
  06 ? 08 1 kz ? L3 Ds ? D,
• 1.77M
  5M v2, cp, D
  thermalization
• 
  
• FEE Upgrade 04 ? 05
  05 ? 06 1 kz ? L3 Ds ?, D,
• 250k
  2.5M v2, cp, D
  thermalization
  
  
• Forward Hadron
  before next d-Au forward jets, mono-jets,
• Calorimeter
  TBD collins
  fragmentation