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Today we’ll tell you about
Who we are & our role in PHENIX (Barbara)Physics focus of the groupPast AchievementsFuture Goals
Synergies between heavy ion & spin And with Theory, Particle Physics and NSL
Spin Program at Stony Brook (Abhay) PHENIX Upgrades activities (Axel) Stony Brook graduate students’ work Tour of our labs (Tom & Abhay)
Heavy Ion Physics Focus
PAST
Jet quenching via inclusive high pT charged hadrons in Au+Au, d+Au
Thermal physics via identified hadron spectra in Au+Au Cronin effect (d+Au)
Charm via single e±
Thermal, charm e+e- pairs
PRESENT
Jet fragmentation fn. Away-jet modification
Energy transport
Baryon-jet correlation
Charm E loss, via single e± to high pT
Thermal via conversions d+Au, AuAu
e+e- pairs
FUTURE
jets as plasma probes multi-particle correlations energy dependence (+LHC)
-jet correlations
Charm via displaced e±
Thermal radiation, charm via low & intermediate mass e+e- pairs
Senior group members
FacultyAxel Drees Tom HemmickBarbara JacakAbhay Deshpande
Research Assistant ProfessorRalf Averbeck
StaffVlad Pantuev (Senior Scientist)Richard Hutter (Technician)
Research supportDOE (group operations)
NSF for Grid research HBD construction at SB
Heavy Ion Graduate Students
Anne Sickles (PhD→BNL)Jamil Egdemir (PhD→Wake Forest U) Matt NguyenAlan DionTorsten DahmsSarah CampbellHaijiang GongMichael McCumberHarry ThemannJason KaminZvi CitronBill Anderson (MSI)
Summer 2006 Megan JuszkiewiczMatt DurhamNikki Cassano
Spin students Kieran BoyleRob BennettNathan MeansPrasad Hegde
Centrality Dependence
Dramatically different and opposite centrality evolution of AuAu experiment from dAu control.
Showed that jet suppression is clearly a final state effect!
Au + Au Experiment d + Au Control
thesis of J. Jia
d+Au analysisby Jia & Anne Sickles
heavy quarks and jet volcano at QM2005
~ same energy loss for charm & light quarks
energy loss not all radiative also by collisions
theses of J. Edgemir, Sergey Butsyk (run2) & Alan Dion (run4)
Analysis and compilationby Mike McCumber
SB contribution to existing tools
Drift ChamberRICH PMT array
Tracking, Momentum Reconstruction in Central
Arms
Analysis Coordinator!
2006 Run Coordinator
Upgrades Coordinator
PWG Conveners
University Contributions to the Group
2 New York State PositionsPantuev, Frantzcollaborate with Rich Lefferts, Andrzej Lipski on HBD
Lab, clean room, assembly spaceBenefit from Nuclear Structure Lab
Subsidized Electronics and Machine shops$44/hour electronics, $37/hour machine
Matching funds for capital equipmentDrift Chamber FEE, HBD
Strong nuclear theory group (Brown, Shuryak, Zahed Wiedemann) + YITP (Sterman)
Most measurements planned for the future are based on hard scattering Sensitive to gluon or spin structure of nucleons or the nucleus Probe quark or nuclear matter ala “Rutherford experiment” or DIS
Basic processes utilized:Parton-parton scattering: leading h or 0, angular correlations, jet production
Gluon-gluon fusion: open heavy flavor production, quarkonia
Quark-gluon Compton scattering: direct photons and -jet
Spin synergy: Hard Probes for pp & AA
q
qg
g
cg
c
central arms + VTX + HDB/TPC + NCC
central arms + VTX
central arms + VTX + HBD/TPC + NCC
q
gg
q
Example of synergy with theory
Mach cone? Jets may travel faster than the speed of sound in the medium Shock plasma by depositing energy via gluon radiationQCD “sonic boom”
+/-1.23=1.91,4.37 → cs ~ 0.33 (√0.33 in QGP, 0.2 in hadron gas)
dN
/d(
)
signal electron
Cherenkov blobs
partner positronneeded for rejection e+
e-
pair opening angle
Full scale prototype
Large acceptance displaced vertex detector( and < 1), < 100 m
D, B → e + hadrons (semi-leptonic decay)
Toward Future Physics at RHIC GEANT model
Strip Detectors (80 m x 3 cm) at R ~ 10 & 14 cm
Hybrid Pixel Detectors (50 m x 425 m) at R ~ 2.5 & 5 cm
||<1.2 ~ 2zcm
e+ e -
e+ e -
Hadron blind detector to reject Dalitz background
~ 1 m
New Future Directions
eRHIC to study e + p and e + A (cold, dense gluonic matter)More from Abhay on this
New faculty search to join ATLAS/heavy ion program
Focus on jet modificationCollaborate with USB particle physics groupMutual interest in jet reconst. and inner trackingFirst planning discussions w/ John Hobbs (USB) US-ATLAS HI collaboration
what is a plasma?
4th state of matter (after solid, liquid and gas) a plasma is:
ionized gas which is macroscopically neutralexhibits collective effects
interactions among charges of multiple particlesspreads charge out into characteristic (Debye) length, D
multiple particles inside this lengththey screen each other
plasma size > D
“normal” plasmas are electromagnetic (e + ions)quark-gluon plasma interacts via strong interaction
color forces rather than EMexchanged particles: g instead of
ideal gas or strongly coupled plasma?
Huge gluon density! estimate = <PE>/<KE>
using QCD coupling strength g<PE>=g2/d d ~1/(41/3T)
<KE> ~ 3T ~ g2 (41/3T) / 3Tg2 ~ 4-6 (value runs with T)
for T=200 MeV plasma parameter
quark gluon plasma should be a strongly coupled plasmaAs in warm, dense plasma at lower (but still high) Tother examples: dusty plasmas in space, cold atoms
such EM plasmas are known to behave as liquids!
> 1: strongly coupled, few particles inside Debye radius