1. New questions and needs

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sPHENIX upgrade for a next US-J project
ShinIchi Esumi, Univ. of Tsukuba for the
PHENIX/US-J collaboration
1. New questions and needs 2. sPHENIX concept and
acceptance 3. soft physics and thermal photons 4.
critical point and fluctuation 5. jets and hard
probes 6. detector RD, schedule and plan
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New questions from RHIC LHC data!

• How is thermalization achieved so rapidly?
• Are there quasiparticles in the quark gluon
  plasma? If so, when and what are they?
• What is the mechanism for quark/gluon-plasma
  interactions? Plasma response?
• Nature of QCD matter at low T but high ??
• At what scales is the coupling strong?
• Is there a relevant (color) screening length?
• Are there novel symmetry properties?

To answer these questions
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current PHENIX
future sPHENIX
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(No Transcript)
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Collective expansion and freeze-out
photons
hadrons
v2
v2 of hadrons
thermal photon (low pT) surprisingly large
v2 prompt photons (high pT) reasonably small
energy loss
quark coalescence
v2 of direct photons
hydro expansion
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Initial fluctuation followed by collective
expansion
WMAP
peripheral
central
Initial density distribution
PHENIX
PRL107, 252301, (2011)
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Fluctuations close to the Critical Point
higher moments of p-pbar distribution
S. Gupta, QM2011
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Jet quenching with reconstructed jets
Closer and closer to the initial parton energy
Gamma trig.
Jet (large R) trig.
Jet (small R) trig.
?0(hadron) trig.
more and more surface bias given by energy loss
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Energy dependence is a key tool for understanding
RHIC provides a sweet spot
Lattice calc.
rare probe scan 50 lt vsNN lt 200 GeV asymmetric
systems AuAu , CuAu , UU asymmetric energies
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Direct photon flow
Charged hadrons, photons and electrons
ee-, J/psi
Si cylindrical GEM
tracking under high-multiplicity
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Jets in medium
jet-reconstruction study

• Capable with inclusive jets of ET2065 GeV and
  R0.20.3 in central Au-Au
• Lower energy and/or larger R jets for
  non-central Au-Au and light ions

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Jet chemistry particle composition within a jet
cone wide coverage PID for e-by-e study
fast MRPC for Jet chemistry and wide coverage PID
PID with current system
p
TOF vs 1/p (with Aerogel Cherenkov veto)
K
?
MRPC TOF
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Existing detectors and RDs
VTX
EMC options
VTX
possible new technologies from yesterday
afternoon RD session ! (advanced pixel sensor,
TPC, PID,,,) re-use the CDF (or other old)
solenoid or a new magnet construction
Y. Arai, KEK, yesterday afternoon RD session III
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Plans
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Cost estimate for Strawman initial implementation
Tungsten Scintillator EMCAL hlt1, 2p (Dh x Df
0.024 x 0.024)
HCAL
Magnet
EMCAL
Fe Scintillator HCAL hlt1, 2p (Dh x Df
0.1 x 0.1)
(w/o pre-shower)
VTX
Jets in medium
EMCAL 7.5 M HCAL 3.9 M Magnet 3.5 M ? US-J
?! -----------------------------------------------
--------------------------------------------------
----------------- Si-W pre-shower 4.5 M ?
US-J or MEXT ? or PID (cost estim. underway) or
tracking (cost estim. underway) ------------------
--------------------------------------------------
---------------------------------------------- DOE
to provide initial 20.0 M (including overhead
contingency) -------------------------------------
--------------------------------------------------
--------------------------- 15-20 of total 20M
US-J investment would be 34M ? 4864 MY/year
for 5 years
(existing)
Direct photon flow
Magnet Existing CLEO II R1.55 m, L3.8
m, B1.5T CDF R1.5 m, L 5.07
m, B1.5T D0 R 0.6 m, L 2.73 m,
B 2T New R 1.0 m (this estimation) R
0.6 m (Decadal Plan)
Jet chemistry
ee-, J/psi
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Summary New questions and needs sPHENIX
concept QGP physics at RHIC detector RD,
schedule and plan
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Backup --- answers to the earlier questions
Thermalization mechanism gdir yield, spectra
flow Coupling scale quasiparticle search charm
hard (not thermal) probe c vs. b in QGP Critical
point energy scan Non-monotonic
behavior parton-plasma interaction Jets 50 GeV,
g-jet Ejet, l, qmass, Fjet dep. of dE/dx Jet
virtuality medium scale Screening length study
as function of vs, pT QCD in cold, dense
(initial) state y dependence in dAu Gluon
saturation scale, EIC
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J. Nagle
pp (fit to ATLAS data) PbPb E1 gt 100 GeV dash
includes E2 gt 25 GeV qhat 30 GeV/fm2
B. Mueller
pp (fit to PYTHIA) PbPb E1 gt 30 GeV dash
includes E2 gt 5 GeV qhat 10 GeV/fm2