Transcript Event-by-Event Average pt Fluctuations at 62 GeV

The PHENIX Potential in the
Search for the QCD Critical Point
Workshop on the Critical Point and the Onset of
Deconfinement – 7/4/06
Jeffery T. Mitchell for the PHENIX Collaboration
(Brookhaven National Laboratory)
Outline
• PHENIX Detector and Performance
• Demonstrating Capabilities with Current Measurements
• Contribution of Upgrades
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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The PHENIX Detector 2006
Charged Particle Tracking:
Calorimetry:
Pb Scintillator
Pb Glass
Event Characterization:
Beam-Beam Counter
Zero Degree Calorimeter
Shower Max Detector
Forward Calorimeter
Drift Chamber
Pad Chamber
Time Expansion Chamber/TRD
Cathode Strip Chambers (Mu Tracking)
Particle ID:
Time of Flight
Ring Imaging Cerenkov Counter
TEC/TRD
Muon ID (PDT’s)
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Current PHENIX Datasets
p+p
d+Au
Au+Au
Cu+Cu
22.4 GeV
62.4 GeV
130 GeV
200 GeV
Run 1 - 3
Run 4 - 5
CuCu 200GeV
CuCu 62.4GeV
1.08 Billion Events
630 Million Events
CuCu 22GeV
p-p
200GeV
48 Million Events
6.8 Billion Events
157TB on tape
42TB on tape
Run 6
Advances in data logging and
the implementation of “multievent buffering” increased
our Event rate dramatically in
Runs 4 and 5
3TB on tape
286TB on tape
-----------------------------488 TB on tape for Run 5
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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
No apparent show-stoppers for RHIC
collisions at Ecm = 5-50 GeV/n




Small set of specific energies (and
species?) should be a workshop
deliverable for planning:




2.5,3.2,3.8,4.4… GeV/n total beam energy
Studies that should be done soon:


Only equal energies
Unequal species possible only if minimum
rigidity > 200 T-m
Without cooling  long vertex distribution
A ~1 day study period at low total beam
energy to identify power supply, lifetime,
tuning issues/limitations
Low-current superconducting magnet
measurements
Pre-cooling in AGS  10x luminosity ?
Electron beam cooling would make this a
fantastic facility: ~100x luminosity, small
vertex distribution, long stores.
Expected whole vertex minbias event rate [Hz]
RHIC low-E Feasibility
T. Roser, T. Satogata
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Initial Machine Projections
Mode
Beam
Energy
[GeV/u]
Nbunches Ions/bunc b* Emittanc
h
[m]
e
[109]
[m]
Lpeak
[cm-2s-1]
Au-Au
2001-2
9.8
55
0.6
3
15
8.01024
Au-Au
2003-4
31.2
45
1.0
3
15-30
1.21026
Au-Au
9.8
55
1.2
10
15-40
1.01025
Au-Au
2.5
55
1.0
10
15-30
1.11023
Au-Au
25
55
1.2
3
15-40
2.01026



T. Roser,
Assumes expected luminosity scaling as 3 below 9.8 GeV/u
T.
b*/aperture and integrated luminosity tradeoffs must be studied
Projections do not include potential improvements



Satogata
Electron and stochastic cooling (peak and integrated luminosity)
Lattice modifications to mitigate IBS (integrated luminosity)
Total bunch intensity from vacuum improvements (peak luminosity)
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Centrality Determination: 62, 200 GeV
peripheral
central
Participant
b
To ZDC
15-20%
1015%5-10%
To BBC
Spectator
200 GeV
0-5%
0-5%
62 GeV
Multiplicity distribution
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Centrality Determination: <25 GeV
• At low beam energy, the
BBC acceptance can cover
spectator nucleons,
affecting the linearity of the
response.
• For 22.5 GeV Cu+Cu, pad
chamber 1 is used for the
centrality determination.
• Only 4 centrality bins (010%, 10-30%, 30-60%, and
60-88% are defined.
• Using PC1 can introduce
autocorrelations into some
measurements.
• A new centrality detector
would be very useful for
PHENIX at low energies.
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: ET, Multiplicity
PHENIX preliminary
BEHOLD THE LOW
ENERGY PHENIX DATA…
PHENIX preliminary
 “Classical” Shape: Peak, Valley, Edge.
 Top centrality classes are shown
individually.
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: ET, Multiplicity
62.4 GeV PHENIX
Preliminary
PHENIX preliminary
PHENIX preliminary
 Consistent behavior for ET and Nch
 Both increase with energy
 Both show a steady rise from peripheral to central collisions
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: <ET>/<Nch>
 The ratio <ET>/<Nch> increases by
~20% from 19.6 GeV to 200 GeV and
stays the same between 200 GeV
and 130 GeV
 Consistent with the average
particle momentum increase
between those two energies.
 The ratio <ET>/<Nch> is
independent of centrality
 Since trigger and centrality related
uncertainties cancel out, the
flatness of the curves is precise.
PHENIX preliminary
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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√sNN dependence
 Both ET and Nch show log-scaling.
 Works even better on Nch for Np = 350.
[The band on the right is a 2σ error]
 Extrapolation to LHC dNch/dη =
(6.1±0.13)×(0.5Np).
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: Charged Hadron Yields
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: Charged Hadron Spectra
Blast wave
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Charged hadron identification in PHENIX
PHENIX EmCal (PbSc)
Time of Flight
- /K separation ~ 3 GeV/c
- K/p separation ~ 5 GeV/c
Electromagnetic Calorimeter
- /K separation ~ 1 GeV/c
- K/p separation ~ 2 GeV/c
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: pT spectra for pions
Filled symbols : +
Open symbols : Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: pT spectra for kaons
Filled symbols : K+
Open symbols : KJeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: pT spectra for protons
* No weak decay feed-down correction applied
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: pT spectra for antiprotons
* No weak decay feed-down correction applied
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: -/+, K-/K+ vs. pT
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: p/ Ratios


p/+ ratio : increasing as a function of sNN.
p/- ratio : decreasing as a function sNN.

Cu+Cu 22.5 GeV central data reaches the p+p values.
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: pbar/p ratio vs. pT
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: RAA for pions
• p+p reference: global fit
of pion data at s ~23 GeV
(D. d’Enterria).
Error notations:
- Error bars: statistical error for
Cu+Cu spectra
- Gray boxes:
1) sys. error for p+p
reference.
2) sys. error for Cu+Cu
spectra.
- Lines: Ncoll error (1.)
• p+p reference: global fit of
pion data at s ~62 GeV.
• nucl-ex/ nucl-ex/0411049,
D. d’Enterria.
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: RAA for kaons
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: p, RAA
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement:
New Run4 Data
0

pT Spectra
Cu+Cu 200 GeV
2.2 B sampled
Au+Au 200 GeV
Luminosity 241b-1 (sampled)
1.5B events
New Run5 Data
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: 0 pT Spectra

Go near SPS
Energies



p+p data at 21.7 –
23 GeV
Use of
parameterization
as reference
0
3 days of RHIC
Run5


6.8M Events after
quality cuts
Centrality via PC1
multiplicity
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: 0 RAA
Similar Npart (WA98 : 132, PHENIX: 140)
same behaviour
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: 0 RAA
nucl-ex/0504001
Cu+Cu @ 22.4 GeV
consistent with SPS
(Note: different system size)
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: v2
200 GeV Au+Au
See Roy Lacey’s talk
PHENIX preliminary
 Transverse kinetic energy scaling works for
a large selection of particles
 Supports the idea that all particles originate
from a common flow field
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: v2
200 GeV Au+Au
See Roy Lacey’s talk
 Scaling holds over
the whole range of KET
v2 h  KET   nv2 p  KET / n
PHENIX preliminary
 KET/n gives
kinetic energy
per quark, assuming
that each quark
carries equal fraction
of kinetic energy
of hadron
Observation of scaling of v2 with quark
kinetic energy could be used as input for
recombination models
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Critical Exponent analysis of
centrality-dependent fluctuations

Let’s assume that the increased fluctuations are indicative of
critical behavior. Then, it is expected that a) the system can be
described by critical exponents, and b) all systems can be
described by the same set of critical exponents. In the Grand
Canonical Ensemble:
  2 




 1
k NBD
k BT

kT

V
The critical exponent for compressibility is represented by the
kT
symbol  and is described by
' T  Tc 
c
T
k

 1
 A(
TC
)
Replacing and solving for 1/kNBD gives (A=constant,
  2 
T=Temperature, V=volume)
T

1
 1 
 A
k NBD


V
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
 T  Tc 

 TC 

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Measurement: Multiplicity Fluctuations 
Critical Exponents?
0.2 < p < 3.0 GeV/c
 2 
k BT
 

kT

V
T
T N
p
part
Comparison to NA49
measurements at SPS energies.
All scaled variance data have
been corrected for impact
parameter fluctuations from their
5% and 10% wide centrality bins
and scaled to lie on the 200 GeV
Au+Au curve. The fits use =1.2
(p=1/3); or =1.1 (p=0). The
typical value is 1.2-1.3. The NA49
data amazingly exhibit the same
universal behavior!
PHENIX
Preliminary
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Measurement: <pT> Fluctuations
S. Adler et al., Phys. Rev. Lett. 93 (2004) 092301.
0.2 < pT < pTmax
Highlights: Non-random fluctuations are observed. Non-monotonic centralitydependence. Strong pT-dependence. pT fluctuations appear to be driven by high pT
particles. The shape can be explained using a PYTHIA-based simulation estimating the
relative contribution of correlations due to jets.
However, simulations show that the sensitivity to temperature
fluctuations is strongly multiplicity-dependent. PHENIX sensitivity takes a
large hit at low beam energies.
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Run-3:
DesignPHENIX
Configuration!
The
Upgraded
Detector
Charged
Particle Tracking:
 Detector
Redundancy
Drift Chamber
 Fine
Granularity, Mass Resolution
Pad
Chamber
Time
Expansion
 High
DataChamber/TRD
Rate
Cathode Strip Chambers(Mu Tracking)
 Good Particle ID
Forward Muon Trigger Detector
High rate trigger
Vertex
Limited
Acceptance
Si
Tracking
Detector- Barrel (Pixel + Strips)
Si Vertex Endcap (mini-strips)
Precision
Particle ID:
Charged
Time ofParticle
Flight Tracking:
vertex tracking
Drift
Chamber
Ring
Imaging
Cerenkov Counter
Pad
Chamber
TEC/TRD
TimeID
Expansion
Muon
(PDT’s) Chamber/TRD
Cathode
Strip Chambers(Mu
Tracking)
Aerogel
Cerenkov
Counter
Particle
ID: Resistive Plate Chamber ToF
Multi-Gap
PID (k,,p) to 10 GeV
Time of
Flight
Hadron
Blind
Detector
Ring Imaging Cerenkov Counter
Calorimetry:
Rejection of Dalitz/Conv.
PbTEC/TRD
Scintillator
PbMuon
GlassID (PDT’s)
Aerogel
Counter
Nose
ConeCerenkov
Calorimeter
Calorimetry:
Muon Piston Calorimeter / coverage to very fwd FCAL
SMD/
Pb Scintillator
Event Characterization:
Pb Glass Counter
Beam-Beam
Event
Characterization:
Zero
Degree Calorimeter/Shower Max Detector
Multiplicity
Vertex Detector (Si Strip,Pad)
Forward
Calorimeter
Beam-Beam
Reaction
PlaneCounter
Detector
Zero Degree Calorimeter/Shower Max Detector
Data Acquisition:
Forward
Calorimeter
DAQ
Upgrade
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
FCAL
34
Extended PID: AGEL + TOF-W


“An aerogel and time-of-flight system to provide complete
/K/p separation for momenta up to ~10 GeV/c.”
Project well underway


Aerogel completely installed
(first physics results now available)
TOF-W (‘Time-Of-Flight-West’)



Partial funding: J. Velkovska (Vanderbilt) OJI
Prototypes tested in Run-5
System to be installed in next shutdown
n=1.018
+2 GeV/c
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Reaction Plane
Det (RxNP)
•Scintillator paddles with lead converter at
1<||<3
•Measure reaction plane
•resolution better by factor 2
•Trigger counter for low energy
running, where  is reduced from
beam energy
RxNP
resolution
BBC RP
resolution
0%
25%
50%
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
75%
100%
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partner positron
needed for rejection
Hadron-Blind Detector (HBD)


“A hadron-blind detector to detect
electrons from near the vertex.”
Dalitz rejection via opening angle



e-
e+
q
pair
opening angle
HBD: a novel detector concept:







Identify electrons in field free region
Veto electrons with partner
Cherenkov
blobs
windowless CF4 Cherenkov detector
50 cm radiator length
CsI reflective photocathode
Triple GEM with pad readout
reverse bias  hadron blind
2x135 in  and || < 0.45
Construction 2005-2006, Installation
in 2006 (4-6 weeks from now)


Funding provided by DOE, NSF,
Weizmann, Stony Brook
R&D completed
 e+ e o  e+ e “combinatorial
pairs”
S/B ~ 1/500
all signal
total background
Irreducible charm bkg
charm signal
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Silicon Tracker

“A vertex detector to detect displaced vertices from the decay
of mesons containing charm or bottom quarks.”


~$3M committed by RIKEN
MIE proposal submitted to DOE Aug-04:




DOE Cost & Schedule review May, 2006
Total Project Cost = $4.6M
In President’s Budget for FY07
Very active ongoing R&D program
||<1.2
 ~ 2
z ~± 10cm
Hybrid Pixel Detectors (50 m x 425 m) at R ~ 2.5 & 5 cm
Strip Detectors (80 m x 3 cm) at R ~ 10 & 14 cm
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Nosecone Calorimeter (NCC)


“A forward calorimeter to provide photon+jet
studies over a wide kinematic range.”
Forward physics with PHENIX





Large acceptance calorimeter
EM calorimeter ~42 X/Xo
hadronic section (1.6 l/l0)
Tungsten with Silicon readout
Extended physics reach with NCC

Extended A-A program




high pT phenomena: 0 and -jet
χc → J/ +  (deconfinement)
Small x-physics in p(d)-A
Polarized proton physics


0.9 <  < 3.0
10 X
Acceptance of
Central Arms
G(x) via -jet
Status



Submitted to DOE for FY08 funding start
New expert groups join R&D
(Moscow State, Czech groups)
Construction FY08 – FY10
Constraint
-space
W-silicon sampling
calorimeter
40 cm from collision vertex
20 cm total depth
Densest
highest spatial resolution
20 cm
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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NCC
NCC
EMCAL
HBD
MPC
EMCAL
MPC
0 coverage
2
Future PHENIX Acceptance for Hard Probes
VTX & FVTX
-3
-2
-1
0
1
2
3 rapidity
(i) 0 and direct  with combination of all electromagnetic calorimeters
(ii) heavy flavor with precision vertex tracking with silicon detectors
combine (i)&(ii) for jet tomography with -jet
(iii) low mass dilepton measurements with HBD + PHENIX central arms
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Upgrade Schedule Scenario
2002 2003 2004
2005
2006
2007
2008 2009
2010
2011
Aerogel
RxNP
MPC
TOF.W
HBD
WTrigger
VTX-barrel
VTX-endcap
NCC
DAQ
R&D Phase
Construction Phase
Ready for Data
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Conclusions




RHIC is capable of performing a low energy scan.
PHENIX is capable of producing high quality measurements
now and in the future on the wide variety of observables that
could be needed to isolate the QCD critical point.
PHENIX would benefit from a centrality detector designed
specifically for low energy running.
However, to do cover all the bases, it would be nice to complete
the program with:




Enough energy steps with sufficient statistics to map out any inflections
about the critical point.
More than one species in order to investigate universal behavior and
critical exponents near the critical point.
Companion p+p and d+Au data at each energy in order to reduce any
systematic errors in measuring baseline distributions – important for RAA
measurements.
Estimated time for a 3 correlation function measurement: 18
days at 20 GeV
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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a
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Thanks to those who contributed
directly to this presentation…












Martin Purschke
Alexander Milov
Tatsuya Chujo
Peter Steinberg
Christian Klein-Bosing
Christoph Baumann
Henner Buesching
Hiroshi Masui
Michael Issah
Todd Satogata
Mickey Chiu
… and many more
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Happy Independence Day (USA)
Photos from Round 1:
Italy 1, USA 1
Good luck to Italy AND Germany tonight in the World Cup Semi!
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Auxiliary Slides
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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PHENIX Static Backup Slide
 Beam-Beam Counters:
 64 Cherenkov Counters
 3.1<|η|< 3.9 Δφ = 3600
 σvertex= ~5mm (central)
 σt= ~100 ps
 Pad Chamber Detectors:
 MWPC with binary pad
readout
 2.5m and 5.0m from the IP
 |η|< 0.35 Δφ = 900
 σφ= 1.4mrad (3.5mm PC1)
 ση= 0.7×10-3 (1.7mm PC1)
 Double Hit Resolution
~4cm
 Electromagnetic
Calorimeter:
 Lead+Scintillator 18 X0
 5.1m from the IP
 |η|< 0.38 Δφ = 900
 σE= 8.1%/√E[GeV]
×2.1%
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Recalculation between systems.
 In C.M.S.:
 In C.M.S.:
 At Mid-Rapidity: ET~mT
 dNch/dy ≈ 1.25 dNch/dη
 dET/dy ≈ 1.25 dET/dη
 In Lab:
 In Lab:
 dNch/dy ≈ 1.04 dNch/dη
 dmT/dy ≈ 1.25 dET/dy
 dET/dy ≈ dET/dη
 Recalculation parameters are “rather” independent on energy
 A systematic error of 5% is assigned to any recalculated value
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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Comparison to other SPS results.
 Good agreement between PHENIX measurements at 19.6 GeV and
SPS measurements at 17.2 GeV in both measured values.
 SPS spread of the data is larger than RHIC, but the same averaging
should be possible to reduce the systematic errors.
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
49
Measurement: Multiplicity Fluctuations  Critical
Exponents?
0.2 < p < 3.0 GeV/c
 2 
k BT
 

kT

V
T
T N
p
part
Comparison to NA49
measurements at SPS energies.
The NA49 scaled variance data
have been corrected for impact
parameter fluctuations from their
10% wide centrality bins and
scaled up by 20% to lie on the
200 GeV Au+Au curve. The fits
use =-1.2, p=1/3; or =-1.1,
p=0. The NA49 data amazingly
exhibit the same universal
behavior!
PHENIX
Preliminary
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
50
PHENIX Sensitivity: Modelling a fluctuation
Goal: Produce a fluctuation that does not change the mean or
variance of the final inclusive distribution.
• The final inclusive distribution (fixed by observation) can be
expressed as:
dN
 ( pt , p, b)
dpt
where T = 1/b is the inverse slope parameter of the distribution.
• Consider an event sample with two classes of events.
Define q = Nevents, class 1 / N events, total
• The distribution for the two component fluctuating sample
can be taken as:
f ( pt )  q  ( pt , b1, p1)  (q 1)  ( pt , b2, p2)
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
51
PHENIX Upgrades Physics Capabilities
X upgrade critical for success
O upgrade significantly enhancements program
High T QCD
PHENIX Upgrades
Spin
e+e- heavy
jet
quarkonia
flavor tomography
hadron blind detector (HBD)
X
vertex tracker (VTX)
X
X
O
 trigger
W
G/G
O
O
Low x
X
X
forward calorimeter (MPC)
X
forward Vertex tracker ( FVTX)
X
forward calorimeter ( NCC)
RHIC luminosity
O
O
O
O
O
O
O
O
O
O
O
O
X
X
X
O
O
O
PHENIX upgrades designed for optimum
physics output with RHIC II luminosity
Jeffery T. Mitchell - Workshop on the Critical Point and Onset of Deconfinement – Florence, Italy – 7/4/06
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