June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Z akopane Poland 1 Soft sector: promises, promises... ~ 10 GeV/fm 3 >> C (Bjorken / hydro) • Early thermalization (v2 / hydro) • T chem ~ T H ~ T c ~ 170 MeV b ~ 30-40 MeV -- near baryon free connection to lattice? • further evolution (PdV work?) & expansion leading to... • cooling and bulk collective motion (pT spectra, v2, HBT, K-) Can we use an external probe to explore further?
Soft sector: promises, promises. ~ 10 GeV/fm 3 >> C (Bjorken / hydro) Early thermalization (v2 / hydro) T chem ~ T H ~ T c ~ 170 MeV b ~ 30-40 MeV -- near baryon free connection to lattice? further evolution (PdV work?) & expansion leading to... - PowerPoint PPT Presentation
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June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 1
Soft sector: promises, promises...
~ 10 GeV/fm3 >> C (Bjorken / hydro)
• Early thermalization (v2 / hydro)
• Tchem ~ TH ~ Tc ~ 170 MeV
b ~ 30-40 MeV -- near baryon free connection to lattice?
• further evolution (PdV work?) & expansion leading to...
Important result!Several complicated (& diff) ways to get suppression?Several canceling effects?
Look closer in a more natural way…
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 38
If we are looking at energy loss…
…why quantify downward shift of spectrum (as in RAA)?
PHENIX PRL 2003
It seems more natural to quantify leftward shift.[Tannenbaum/Mioduzewski]
NB: ignores• Cronin (see jets() coming up…)• mods in FF (logical to look at shift of
partons not their fragments)
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 39
ÿ p-p 0 spectrum: power law:
€
dn
dpT
2=
A
pT
n with n = 8.1 ±0.1
ÿ p T shift , UTloss
UT
UT
ST pSpSpp )1()( −=−=
o pTU = pT with no energy loss
o pTS = pT with energy loss
o Sloss = (pTU- pT
S)/ pTU
= fraction of pT lost
)2/(11 −−= n
AAloss RS
…then let’s look at energy lossEmpirical energy loss
Tannenbaum/Mioduzewski
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 40
ÿ p-p 0 spectrum: power law:
€
dn
dpT
2=
A
pT
n with n = 8.1 ±0.1
ÿ p T shift , UTloss
UT
UT
ST pSpSpp )1()( −=−=
o pTU = pT with no energy loss
o pTS = pT with energy loss
o Sloss = (pTU- pT
S)/ pTU
= fraction of pT lost
)2/(11 −−= n
AAloss RS
Initial pathlength dependence seems to work
–Gyulassy, Vitev, Wang:
• 1D expansion, simple geometric scaling Well reproduced by experimental data.
3/2partNE ∝
PHENIX prelimAu+Au √sNN=200 GeV
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 41
Vary pathlength another way…
PHENIX prelimAu+Au √sNN=200 GeV
(deg)
qualitatively OK, now see about consistency…
PHENIX B. Cole, HardProbes 04
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 42
No universal loss versus density path?
€
dncolor
dA∝
dnpart
dA
ρρ 0init
colorcolor )( =Txr
PHENIX preliminar
y
pT > 3 GeV/c
Overlapintegral:
1Dexpansion
ρpart(x,y) vs centrality10-20% 50-60%
• Quantitative consistency required to claim “jet tomography”
• Next level of precision needed to clarify underlying quenching mechanism
• also -tagging, charm/dead-cone, q/g jet selection, correlated quenching signal versus length
• (Role of dynamics in differential analysis may be significant)• cannot just put by-hand some energy loss & find consistency w/BJ
PHENIX B. Cole, HardProbes 04
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 43
PHENIX Preliminary
RAA (2.5<pT<5.0 GeV/c)
Nu
clea
r m
odif
icat
ion
fac
tor
Converter method
Cocktail subtraction method
pT (GeV/c)
HINT of charm suppression??
Too early to tell (May05)
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 44
Backup
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 45
Parton Number Scaling of Elliptic Flow
In the recombination regime, meson and baryon v2 can be obtained from the parton v2 (using xi = 1/n):
( ) ( )
3
2
2 2
2
2
22
2
2
3v 32v2
v
1 2 v
v3 3
v
1 6 v32
and
p pt t
B
p t
Mt t
p tp t
p p
p
p
pp p
⎛ ⎞⎛ ⎞ ⎛ ⎞+⎜ ⎟ ⎜ ⎟⎜ ⎟
⎛ ⎞⎜ ⎟⎝ ⎠=
⎛ ⎞⎛ ⎞+ ⎜ ⎟⎜ ⎟
⎝
⎝ ⎠ ⎝ ⎠⎝ ⎠=⎛ ⎞⎛ ⎞
+ ⎜ ⎟⎜ ⎟⎝ ⎠⎝⎠ ⎠⎠⎝
Neglecting quadratic and cubic terms, a simple scaling law holds:
( ) ( )2 2 2 2an vv23
vd2
v 3M B ptt
tp tpp
pp
⎛ ⎞=
⎛ ⎞= ⎜ ⎟
⎝⎜⎝ ⎠ ⎠
⎟
Originally poposed by S. Voloshin
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 46
Suppression vs Collision Energy
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 47
NO suppression in d+Au!
BRAHMS
Phobos
STAR
PHENIX
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 48
Hadron dependence of high-pt suppression
• R+F model describes different RAA behavior of protons and pions
• Jet-quenching becomes universal in the fragmentation region
Mueller & Fries [Mueller TBS05]
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 49
Centrality dependence of open charm in Au+Au
Compare to (PYTHIA) an event generator tuned for pp collisions…
no largesuppression- unlike lightquarks!
Spectra of electrons from c e + anythingphotonic sources are subtracted
central
peripheral
Comparison to pp should be available this week.
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 50
inclusive ee v2
charmed ee v2
If charm quarks also flow, charm quarks are thermalized and / or suppressed (interact with matter) similarly to the light quarks.
STAR SQM04
nucl-ex/0502009
•charmed electron v2 > 0•rule out an extreme case, charm does not interact with QGP and fragment in vacuum into D meson•get charm quark v2 with quark coalescence assumption
Flowing Charm? [F. Laue TBS05]
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 51
Inclusive Single
PHENIX Preliminary
Run2 AuAu 200 GeV
Direct photons are enhanced w.r.t. production, but it’s just because is suppressed, and the direct photons are in fact binary scaled.
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 52
STAR : nucl-ex/0409033 non-flow reduced
v2{2}
v2{RP}
PHENIX Preliminary
Different ways to reduce non-flow correlation, v2 w.r.t. SMD R.P.
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 53
Sonic boom from quenched jets Casalderrey,ES,Teaney, hep-ph/0410067; H.Stocker…
• the energy deposited by jets into liquid-like strongly coupled QGP must go into conical shock waves, similar to the well known sonic boom from supersonic planes.
• We solved relativistic hydrodynamics and got the flow picture
• If there are start and end points, there are two spheres and a cone tangent to both
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 54
away <pT> dependence on angle (STAR,preliminary)
Preliminary
<pT> (phi) has a dip structure in central AA.
Mach shock wave?
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 55
Viscosity of QGP
QGP at RHIC seem to be the most idealfluid known, viscosity/entropy =.1 or so water would not flow if only a drop with 1000 molecules be made
• viscous corrections1st order correction to dist. fn.:
:Sound attenuation length
Velocity gradients
Nearly ideal hydro !? D.Teaney(’03)
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 56
Comparison Au+Au/p+p at Lower Energies
• Pb+Pb collisions at s ~ 20 GeV at CERN/SPS
Crossing at ~ 1.5 GeV/c
Transverse Momentum (GeV/c)
parton energy loss (if any) is overwhelmed by initial state soft multiple scattering(Cronin effect)
RA
A
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 57
Many measurements measure at high pT(!)
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 58
What data can tell us / what (we think) it has told us /open issues
• Hard Sector:
–incoherence of initial state
• calibration of number of initial hard scatterings (binary), which themselves have calibrated spectrum [charm, gamma, d-Au]
–early system color charge density (not deconfinement!)
• if gluonic bremstrahlung: dNg/d ~ 1000 ~BJ
• BUT… energy loss mechanism unclear (consistent scaling?)
June 2005 mike lisa - Cracow School of Theoretical Physics, XLV - Zakopane Poland 60
What data can tell us / what (we think) it has told us /open issues
• Firm Sector:–“transition bulk to probe” (hadn’t really been considered…)
• clearly something new instead!• ?is there a transition? does all fit smoothly?
–first “calibration” of QGP p.s. structure• hope for well-defined ordered (x-p correlated) system of partons • can we get beyond simple models? entropy issues? connection
between constituent quarks and partons?…
My feeling: solution of open issues in hard & soft sectors willbe well worth it, if we can exploit apparent promise of firm.
Launchpad of next generation program: understanding hadronization