exploring hot qcd matter with alice pheno11, madison wihot qcd matter in alice1 heavy ion...
TRANSCRIPT
![Page 1: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/1.jpg)
Exploring Hot QCD Matter with ALICE
PHENO11, Madison WI Hot QCD Matter in ALICE 1
• Heavy Ion Collisions: what are we after?• ALICE Overview• ALICE results from 2010 Pb+Pb run• Putting together RHIC and LHC:
What have we learned about hot QCD matter ?
Peter Jacobs, Lawrence Berkeley National Laboratoryfor the ALICE Collaboration
![Page 2: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/2.jpg)
QCD Phase Diagram: qualitative view
PHENO11, Madison WI Hot QCD Matter in ALICE 2
Tem
pera
ture ~170
MeV
Baryon chemical potential µB
~few hundred MeV
Deconfined Quark-Gluon Plasma
![Page 3: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/3.jpg)
QCD thermodynamics: calculation
PHENO11, Madison WI Hot QCD Matter in ALICE 3
42
30TgDOF
4T
T [MeV]
QCD on the lattice (B=0)
Cross-over, not sharp phase transition (like ionization of atomic plasma)
Slow convergence to non-interacting Steffan-Boltzmann limitWhat are the quasi-particles? “Strongly-coupled” plasma?
RHIC LHC?
![Page 4: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/4.jpg)
4Hot QCD Matter in ALICE
ALICE is the comprehensive heavy ion experiment at the LHC
Design optimized for huge particle multiplicities of nuclear collisions
ALICE
PHENO11, Madison WI
![Page 5: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/5.jpg)
ALICE vs ATLAS/CMS
PHENO11, Madison WI Hot QCD Matter in ALICE 5
Requirements for heavy ion physics:• measure large-scale collective phenomena:
reconstruct complex hadronic events• precise measurements of heavy flavor, photons, leptons, jets and jet fragments• energy scale
→ robust tracking ~ 100 MeV – 100 GeV→ calorimetry ~ 200 GeV
• low material budget near vertex• particle ID: multiple detector technologies
Requirements for Higgs/SUSY searches:• missing energy signatures: hermetic coverage• energy scale 10 GeV – 1 TeV• tiny cross sections: high rate and rejection capabilities
ALICE favors robust tracking, precision, and low mass over large acceptance, high rate, and huge dynamic range
![Page 6: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/6.jpg)
November 7 2010: First Pb+Pb collisions at √sNN=2.76 TeV
PHENO11, Madison WI Hot QCD Matter in ALICE 6
![Page 7: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/7.jpg)
PHENO11, Madison WI 7
Particle ID: TPC dE/dx
Hot QCD Matter in ALICECopious production of anti-nuclei
![Page 8: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/8.jpg)
Tomography via -conversions
PHENO11, Madison WI Hot QCD Matter in ALICE 8
Inner material understood better than 10%
Compare data and MC
NLO(W. Vogelsang)
M
![Page 9: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/9.jpg)
Charm in Pb+Pb
PHENO11, Madison WI 9Hot QCD Matter in ALICE
J/ψμ+μ-
D+K-
D0K-+
![Page 10: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/10.jpg)
Heavy flavor in p+p: consistency check
PHENO11, Madison WI Hot QCD Matter in ALICE 10
Compare directly measured electrons and electrons calculated from D-decay
good agreement at low pt (charm dominant)
![Page 11: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/11.jpg)
Measuring collision geometry I
PHENO11, Madison WI Hot QCD Matter in ALICE 11
Nuclei are “macroscopic”characterize collisions by impact parameter
Correlate particle yields from ~causally disconnected parts of phase space
correlation arises from common dependence on collision impact parameter
![Page 12: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/12.jpg)
Measuring collision geometry II
PHENO11, Madison WI Hot QCD Matter in ALICE 12
For
war
d ne
utro
ns
Charged hadrons ~3
• Order events by centrality metric• Classify into percentile bins of “centrality”
HI jargon: “0-5% central”
Glauber modeling• Nbin: effective number of binary nucleon collisions (~5-10% precision)• Npart: number of (inelastically) participating nucleons
![Page 13: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/13.jpg)
ALICE Results I: hadron multiplicityPRL, 105, 252301 (2010), arXiv:1011.3916
√sNN=2.76 TeV Pb+Pb, 0-5% central, |η|<0.5
2 dNch/dη / <Npart> = 8.3 ± 0.4 (sys.)PHENO11, Madison WI 13Hot QCD Matter in ALICE
![Page 14: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/14.jpg)
dNch/dη: model comparisons
pp extrapolation
pQCD-based MC
Saturation
PRL, 105, 252301 (2010), arXiv:1011.3916
dNch/dη = 1584 ± 76 (sys.)
√sNN=2.76 TeV Pb+Pb, 0-5% central, |η|<0.5
Energy density estimate (Bjorken):
PHENO11, Madison WI 14Hot QCD Matter in ALICE
![Page 15: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/15.jpg)
dNch/dη: Centrality dependencePRL, 106, 032301 (2011), arXiv:1012.1657
Interpolation between 2.36 and 7 TeV pp
Pb+Pb, √sNN=2.76 TeV
2.5% bins
|η|<0.5
ALICELH
C s
cale
RH
IC scaleRHIC
peripheral central
PHENO11, Madison WI 15Hot QCD Matter in ALICEStriking centrality-independent scaling RHICLHC
![Page 16: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/16.jpg)
dNch/dη vs. centrality: modelsPRL, 106, 032301 (2011), arXiv:1012.1657
Two-component models Soft (~Npart) and hard
(~Ncoll) processes
Saturation-type models Parametrization of the saturation
scale with centrality
Comparison to data DPMJET (incl. string fusion)
stronger rise than data HIJING 2.0 (no quenching)
Strong centrality dependent gluon shadowing
Fine-tuned to 0-5% dN/dη Saturation models [12-14]
Most have too much saturation
Pb+Pb, √sNN=2.76 TeV
Albacete and Dumitru (arXiV:1011.5161):• Most sophisticated saturation model:
evolution, running coupling• Captures full centrality dependence…?
PHENO11, Madison WI 16Hot QCD Matter in ALICE
![Page 17: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/17.jpg)
Collective Flow of QCD Matter
PHENO11, Madison WI Hot QCD Matter in ALICE 17
Initial spatial anisotropy
xy z
py
px
22
22
xy
xy
22
22
2
yx
yx
pp
ppv
Elliptic flow
Final momentum anisotropy
Interaction of constituents
![Page 18: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/18.jpg)
Elliptic flow v2: LHC vs RHIC
PHENO11, Madison WI Hot QCD Matter in ALICE 18
PRL 105, 252302 (2010)PRL 105, 252302 (2010)
Striking similarity of pT-differential v2 at RHIC and LHC
![Page 19: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/19.jpg)
19Hot QCD Matter in ALICE
Shear viscosity in fluids
PHENO11, Madison WI
Shear viscosity characterizes the efficiency of momentum transport
Large quasi-particle interaction cross section Strongly-coupled matterSmall shear viscosity”perfect liquid”
AdS/CFT and kinetic theory: absolute lower bound
![Page 20: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/20.jpg)
Elliptic flow: data vs. viscous hydrodynamic modeling
PHENO11, Madison WI Hot QCD Matter in ALICE 20
e.g. Song, Bass, and Heinz, arXiv:1103.2380
pT-differentialpT-integrated
peripheralcentral
Preferred values: /s(RHIC)=0.16, /s(LHC)=0.20
![Page 21: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/21.jpg)
Shear viscosity: expectations from QCD
PHENO11, Madison WI Hot QCD Matter in ALICE 21
Analytic: Csernai, Kapusta and McClerran PRL 97, 152303 (2006)Lattice: H. Meyer, PR D76, 101701R (2007)
pQCD w/ running coupling
Chiral limit,resonance gas
1/4 Lattice QCD
Temperature (MeV)
If TLHC > TRHIC, expect /s(LHC) > /s(RHIC)
![Page 22: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/22.jpg)
Jet quenching
22
Total medium-induced energy loss:
Plasma transport coefficient:
Apr 4, 2011 LHC News - Sonoma State
Radiative energy loss in QCD (multiple soft scattering):
![Page 23: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/23.jpg)
Jet quenching via leading charged hadron suppression
PHENO11, Madison WI Hot QCD Matter in ALICE 23
Phys. Lett. B 696 (2011)Phys. Lett. B 696 (2011)
peripheral
central
pTpT
p+p reference at 2.76 TeV: interpolated
![Page 24: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/24.jpg)
Jet quenching: RHIC vs. LHC
Apr 4, 2011 LHC News - Sonoma State 24
Phys. Lett. B 696 (2011)Phys. Lett. B 696 (2011)
Qualitatively similar, quantitatively different
Where comparable, LHC quenching is larger
higher color charge density
![Page 25: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/25.jpg)
0 vs charged hadrons/RHIC vs LHC
PHENO11, Madison WI Hot QCD Matter in ALICE 25
RHIC 0, , direct
RHIC/LHC charged hadrons
High pT dependence qualitatively different:• different quenching mechanisms?• consequence of steeper incl spectrum at RHIC? (near phase space limit…)
![Page 26: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/26.jpg)
Jet quenching: comparison to pQCD-based models
Apr 4, 2011 LHC News - Sonoma State 26
X-F Che et al.,arXiv1102.5614 Horowitz and Gyulassy, arXiv1104.4958
Several formalisms different treatments of medium, radiative/elastic e-lossModels calibrated at RHICScale energy density with charged multiplicity (factor~2)
Models systematically predict too much quenching….?• must measure p+p reference at 2.76 TeV (data now on tape)• something missing in the formalism?
![Page 27: Exploring Hot QCD Matter with ALICE PHENO11, Madison WIHot QCD Matter in ALICE1 Heavy Ion Collisions: what are we after? ALICE Overview ALICE results from](https://reader036.vdocuments.us/reader036/viewer/2022070411/56649f425503460f94c61c2c/html5/thumbnails/27.jpg)
Summary and Outlook
PHENO11, Madison WI Hot QCD Matter in ALICE 27
Initial LHC heavy ion run: machine and ALICE worked superbly
First task is to rediscover and compare to the striking heavy ion phenomena found at RHIC
• qualitative similarities but quantitative differences• consistent picture of strongly-coupled (low viscosity) fluid with high color-charge density (opaque to jets)
• discrepancies with models: requires some rethinking
Next for ALICE: qualitative quantitative• quarkonia (deconfinement signature)• charm• full jets (newly commissioned large EMCal)• correlations of many kinds…