Outline for Heavy Quark DR Review, 8:30A 1:00P,

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• Outline for Heavy Quark DR Review, 830A -100P,
• Thursday April 26, 2007, Canyon Complex Room 167
•  
• Introduction to heavy quark program - Pat
  McGaughey (2010 min.) 830-900
• Experiment
• Simulations of physics performance - Hubert van
  Hecke (105 min.) 900-915
• Vertex detector and front end electronics - Gary
  Grim (155 min.) 915-935
• Pixel planes and high density interconnect - Gerd
  Kunde (205 min) 935-1000
• Readout electronics - Mark Prokop (105 min.)
  1000-1015
• Break (10 min.) 1015-1025
•  
• Theory
• Theory intro, Non-equilibrium studies of QGP -
  Emil Mottola (205 min.) 1025-1050
• Energy loss and flow of heavy quarks - Ivan
  Vitev (155 min.) 1050-1110
• Lattice calculations of heavy quarks and EOS -
  Rajan Gupta (155 min.) 1110-1130
•  
• Wrapup - Pat (5 min.) 1130-1135

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Heavy Quarks as a Probe of a New State of Matter
PI Patrick L. McGaughey, P-25
A new state of matter, the quark-gluon plasma
(QGP) has been detected in relativistic heavy ion
collisions at BNL

• Project Goals
• Measure heavy quark suppression and flow to
  determine the properties of QGP,
• using a state-of-the-art silicon vertex
  detector
• Develop theoretical tools necessary to
• interpret the data.

Supported by LANL LDRD Grant, 1.25 M / yr for
FY06-08 LANL groups P-23, P-25, T-8, T-16
DR Review 4/26/07
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The Relativistic Heavy Ion Program

• Fundamental theory (QCD) predicts the existence
  of
• a new state of matter - the quark-gluon plasma
  (QGP)

D. Gross, H.D.Politzer, F.Wilczek
2004 Nobel Prize in QCD Physics
RHIC Physics

• Most extreme and strongly interacting
• matter yet created
• Recreates conditions of early Universe
• Quantitatively establishes QGP properties
• Highest priority of national nuclear physics
• program

H.Politzer, Phys.Rev.Lett. 30, (1973)
One of the Eleven Science Questions for the 21st
Century -

• Are there new states of matter at exceedingly
• high density and temperature?

From National Research Council
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The Big Bang and Little Bang
Recreating the Early Universe in the Laboratory
Detected tracks
?, K
QGP
AuAu
1012 deg
10-24s
10-22s
10-8s
Understanding matter at extreme density and
temperature
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Introduction

• A new state of matter, the quark-gluon plasma
  (QGP), is being probed in collisions of
  heavy ions at RHIC. QGP is composed of
  de-confined quarks and gluons
• Heavy quarks (charm and beauty) are the cleanest
  probe of QGP. Next frontier of QGP physics
• We are constructing a forward silicon
  micro-vertex detector (iFVTX) ? unique heavy
  quark experimental capability. State-of-the-art
  detectors and electronics
• Close collaboration between theory, simulation
  and experiment
• Detailed determination of QGP properties

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Evidence for Strongly Interacting Opaque Plasma
Energetic quarks undergo large energy loss in
the QGP
QGP
Data PHENIX (from cover of PRL!) Predictions
Vitev, LANL JRO
Au?
?Au
? production
RAA
dAu
Absence of QGP effect
AuAu
Strong suppression of pions from AuAu versus
pp and dAu collisions
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Evidence for the Quark-Gluon Plasma
Hydrodynamic Flow
What is flow? - Asymmetry in direction of
produced particles due to pressure gradients in
collision region ? hydrodynamic behavior ? v2 gt 0
QGP
Au
Au
First time hydro limit with QGP
equation-of-state is reached in heavy ion
collisions!
No Flow
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Why Measure Heavy Quarks ?
c? ? 120?m

• Charm and beauty quarks produced early in the
• collision. Survive throughout plasma
  formation and decay.
• Large masses (1.5, 5 GeV) ? precise
  calculations.
• Mass dependence of heavy quark diffusion
  determines QGP
• properties ? viscosity and conductivity.
• Yields of bound heavy quark pairs compared with
  lattice simulations ? energy density and
  temperature.
• Light versus heavy quark suppression
  distinguishes between
• energy loss models for the QGP.

• momentum transfer
• ? mean free path

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Heavy Flavor Suppression in AuAu
D, B ? e X

• Indications of heavy quark
• suppression and flow in AuAu
• collisions at y0, but
• Large systematic errors due to
• poor signal/background. (measures sum of all
  electron sources)
• Separation of charm from
• beauty was not possible.
• Rapidity dependence needed to separate QGP
  effects from cold nuclear matter.

Suppression
Transverse Momentum
Precise measurements of charm and beauty are
needed! Can best be done by measuring their
lifetime with vertex detector
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- Langevin simulations of heavy quark
thermalization, suppression and flow
Theoretical Effort

• Thermal field theory studies of the transport
  coefficients (conductivity and viscosity) in
  the quark-gluon plasma

E. Mottola et al.

• - NLO resummation technique proven correct for
  QED QCD
• Have calculated Damping Rate / Mean Free Path of
  electrons in QED plasma, e.g. the damping rate
  is
• Im SHTL g a T (2.70)
• Method is general relevant for relaxation
  processes of QGP which can be determined from
  microscopic QCD

• Perturbative QCD studies of energy loss and flow
  of heavy flavor in the quark-gluon plasma

I. Vitev et al.
- Have calculated Drag and diffusion
coefficients, confirming partial charm quark
thermalization in QGP
Fractional momentum loss per unit time
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Suppression of electrons from c,b decays
- Novel heavy flavor suppression mechanism
Collisional dissociation of D, B-mesons in QGP
Phenomenological comparison to the large
quenching of the electrons, surprisingly similar
to that seen for light quarks.

• Lattice QCD studies of the critical temp. for
  the QGP phase transition

Status susceptibilities Ntime 6, 8(Action,
Polyakov loop, condensates)
R. Gupta et al.

• Goals Tc, equation of state,
• spectral functions

Lattice Size 8time ?32?32?32space More
realistic quark masses
Susceptibility for light quarks, showing evidence
for QGP transition temp of 190 MeV
Collaborative lattice calculations well underway
at LLNL blue gene supercomputer
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The PHENIX Muon Detectors
iFVTX
Muon Arm
Au
Au
J/????-
Muon Arm
Muon trackers were designed and built by LANL
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Pixel-based Vertex Detector (iFVTX)

• LANL/ FNAL/ Columbia / UNM / NMSU / ISU
  collaboration
• Measures distance of closest approach (DCA) of
  tracks to the primary vertex
• 4 planes of pixel tiles with FPIX chips bump
  bonded to silicon sensors
• Provides a DCA resolution of sDCA lt 100 microns
• Can send data to prototype trigger
• Measures
• D (charm) ? µ X
• B (beauty)? µ X
• by making a vertex cut based
• on the DCA

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iFVTX Design
Pixels
m
50 ?m
400 ?m

• 4 Tracking stations composed
• of Si pixels
• Cover 1/8 of one muon arm
• Electronics recently developed
• by FNAL. Low power, high
• speed and high resolution.

Au
Au
7 cm
Silicon Sensor
Pixel Module
8 chip readout
HDI
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Status - Simulations (Hubert)

• Monte-Carlo simulations of heavy quark decays -
  done
• Simulation of PHENIX geometry with vertex
  detector - done
• Physics performance studied
• Good vertex resolution (lt 100 um in DCA)
• Excellent charm rates
• Good separation of heavy quark decays from
  backgrounds.
• Integrated with PHENIX simulation and analysis
  software

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Status - Detector Elements (Gary)

• Silicon Pixel Sensors
• Fabricated and tested. Excellent yields (93)
• Front End Chip (FPIX2)
• Fabricated and tested. Good yield (82)
• Flip Chip Assembly of Pixel Hybrids (Bump
  Bonding)
• 15 prototype 8-chip modules delivered, initial
  tests good
• High Density Interconnect (Kapton bus)
• Prototypes delivered, working.

Sensor wafer
Pixel hybrids
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Status - Mechanical (Gerd)

• Pixel Plane (printed circuit board)
• Designed, being fabricated
• Mechanical Support Structure
• Design underway
• Finite Element Analysis of Pixel Modules
  Completed
• Good stability versus temperature
• Cooling System
• Heat load lt 200 watts removed by liquid cooling

Pixel Plane layout
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Status - DAQ (Mark)

• Pixel Module Test Stand and software are working
• Calibration and monitoring system prototyped and
  working.
• Readout designed
• Major elements prototyped and working.
• Studies of pixel module completed with test stand
  and underway with ROC/FEM excellent noise and
  thresholds

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Hardware Completion Schedule

• FY06 HDI designed done
• First pixel modules flip chip assembled done
• Si sensors delivered done
• FPIX2.1 readout chips delivered done
• Test bench DAQ systems done
• FY07 HDI Production 05/07
• Pixel plane design and prototype 05/07
• Flip chip Si detectors and FPIX readout chips
  08/07
• FY08 Pixel plane printed circuit boards
  production 10/07
• Pixel module assembly early 08
• DAQ Electronics early 08
• Final vertex detector assembly
  summer 08
• FY09 Full system testing outside of PHENIX
  late 08
• Ready for installation in PHENIX, needs VTX for
  primary
• vertex determination. Useful with p-p, d-Au or
  Au-Au beams

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Backup slides
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Budget for FY07, FY08

• MAJOR ITEMS (Annual budget is 1.25M thru FY08)
• FY07 HDI Production FNAL
• Pixel plane design and prototype 80K
• Flip chip Si detectors and FPIX readout chips
  220K
• DAQ electronics design and prototypes 50K
• Mechanical design and support structure 100K
• Manpower - ExperimentTheory 592K
• FY08 Assemble pixel modules
• Pixel plane assembly
• DAQ Electronics
• Manpower - ExperimentTheory 830K
• FY09 Will request some manpower support for
  installation into
• PHENIX, operation and data analysis

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Why LANL?

• Relativistic Heavy Ion Physics is a strategic
  priority of LDRD
• DR program (Sec. 7.3 Nuclear matter under
  extreme conditions)
• Extensive experience - P-25 developed muon
  physics program
• of PHENIX. We built the muon trackers at RHIC
  and vertex
• detectors at CERN and FNAL
• Convergence of theory, simulation and experiment
  - T- 8 and
• T - 16 expertise in non-equilibrium field
  theory, lattice QCD
• simulations and perturbative QCD predictions
• Essential LANL capability development - Science
  Based
• Prediction for matter under extreme conditions
• Recruitment of outstanding staff - Oppenheimer
  fellow
• Ivan Vitev (T-16 and P-25) is one of the
  worlds experts in
• relativistic heavy-ion theory

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Why Now?

• Successful ER forward silicon design program
  completed
• (2004), electronics just now available
• First direct measurement of heavy quarks at
  RHIC will clinch
• LANL leadership role in national nuclear
  physics program
• Successful completion of this RD expected to
  leverage
• several M in DOE funding for full detector
  covering both
• PHENIX forward arms
• Window of opportunity to make the pivotal
  measurements
• which will influence the future of RHIC and
  heavy ion physics.

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Summary

• Definitive Physics of New State of Matter
• Charm and beauty production cross sections
• Energy loss and flow of charm and beauty in QGP
• Measurement of QGP properties energy density,
  temperature, transport properties, viscosity,
  conductivity
• State-of-the-Art Silicon Vertex Detector
• Si end cap covering ¼ muon arm (4 mini-strip
  layers)
• Unique Opportunity for new LANL Leadership Role
• Theory, simulation and experiment of quark-gluon
  plasma formation and decay in the laboratory
• Nuclear Science Advisory Council Review
• Recommends highest priority of RHIC upgrades for
  PHENIX vertex detector

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PHENIX Decadal Plan
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Heavy Quark Yields, for 1/8 of a Muon Arm

• Rates before application of a
• vertex cut.

Z-Vertex Resolution, ?m
Muon Momentum, GeV
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FNAL Readout Chip Comparison
FSSR and FPIX chip are good candidates for LDRD
project
Signal 24000 e for 300 µm Si Sensor.
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What is innovative about this silicon detector
technology? ? A New Readout Paradigm

• Worlds fastest chips (840 Mbit/sec), 0.25um
  CMOS, developed by FNAL.
• Hits are read out in real-time, ? direct
  triggering.
• Lowest power per pixel and lowest noise (90 uW,
  220e-).
• Large channel count per chip (up to 2816).
• Our vertex detector is first to use this new
  technology.
• Prototypes being tested at LANL and FNAL.

FPIX2.1 Readout Chip 128 column x 22 rows