Overview of flow results from ALICE experiment
ShinIchi Esumi for the ALICE collaboration
Inst. of Physics, Univ. of Tsukuba

contents
Multiplicity and transverse momentum distribution
Source size measurement from HBT
Elliptic and higher order collective flow
Correlation and higher pT

CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

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PID
TPC

V0T0

ZDC

A.Toia, QM11

CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

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Multiplicity in A+A at the highest possible energy
PRL105, 252301 (2010)

factor of ~2 increase with similar Npart dependence
CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

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Identified particle
pT distribution

positive hadrons

collective expansion

locally thermal

negative hadrons

M.Floris, QM11

larger pT shift for heavier particles
larger radial flow than in this hydro model
CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

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kT dependence of HBT radii--- from extended and expanding source ---expandingsourcestatic source

higher pT~1/R

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Univ. of Tsukuba, ShinIchi Esumi

5Beam energy dependenceof 3D source size

factor of ~2 increasein source volume
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Univ. of Tsukuba, ShinIchi Esumi

6Elliptic flow (elliptic event anisotropy) : v2
lower pTxz
higher pT

Reaction planelarger energy loss
by long path length
reaction planesmaller energy lossby short path length

Hydro-dynamical expansion

2nd harmonic amplitudeof azimuthal distribution
with respect to thereaction plane Φ2: v2

φitrack - Φnevent
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Univ. of Tsukuba, ShinIchi Esumi

7v2(pT), <v2> comparison between RHIC and LHC

PRL105 252302

similar hydro properties<v2> still increases with <pT>

CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

8Identified particle v2 and (mT-m0)/nquark scaling--- including strangeness/heavy baryons --remaining
mass orderingfrom stronger
radial flow

R. Snellings, QNP12

Scaling does not work
as good as at RHIC
CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

9Small deviations in (mT-m0)/nq scaled v2
Pb+Pb 2.76TeV

Au+Au 200GeV

Au+Au 39GeV

40-45%

protonprotonPHENIX Preliminary

PHENIX Preliminary

M. Krzewicki, QM11
J. Phys. G38, (2011) 124047

roughly (mT-m0)/nq scaled for all energies
larger pT shift for heavier particles
radial flow increases with energy
CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

10Initial geometricalfluctuation & Higher
harmonic anisotropy vn

B.Alver, G.Roland

S. Jeon

PRL107 032301

CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

11Identified particle v3
nq scalinghydro
M. Krzewicki, QM11
J. Phys. G38, (2011) 124047

hydro: similar mass-splitting at lower pT
nq scaling : similar Baryon / Meson difference at higher pT
The KET/nq scaling for v3 is also not as good as for v2
CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USAUniv. of Tsukuba, ShinIchi Esumi

122-part. correlationin Δφ vs Δη

Pb-Pb 2.76TeV, 2~3GeV/c, J. Jia (ATLAS), QM11--- another way
to measure vn andto describe ridgeand mach-cone ---A. Adare, QM11
arXiv:1107.0285

CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

132-particle azimuthal correlation function--- flow un-subtracted C2 --PRL107 032301

PLB708 249-264

rapidity separated C2 is well described by v2,3,4,5
as naturally expected because of vn{2, |Δη|>1}
CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

The small deviation
gives the soft-hardinterplay…

Univ. of Tsukuba, ShinIchi Esumi

14vn and RAA at low/mid/high pT region

arXiv: 1205.5761

H. Appleshauser, QM11

vn at high pT from suppression dominance given by path lengthtransition from low(soft) to high(hard) pT region
CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

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Summary and outlook- 2.76TeV Pb+Pb collisions at LHC-ALICE- factor of 2 in charged particle multiplicity dNch/dη
- factor of 2 in freeze-out volume from HBT- increased and pronounced radial flow
- similar hydro properties compared with RHIC
- initial fluctuation and expansion drive the vn- soft-hard interplay

CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

16Identified particle v2hydro (arXiv:1105.3226)

hydro (arXiv:1105.3226)

M. Krzewicki, QM11

larger mass-splitting + familiar Baryon/Meson difference
larger radial flow in central collisions than in this hydro model
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Univ. of Tsukuba, ShinIchi Esumi

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S. Jeon

Initial geometrical fluctuation &Higher harmonic anisotropy vn
arXiv:1110.3033

PRL107 032301

CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

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B.Alver, G.Roland

G. Qin, H. Petersen, S. Bass, and B. Muller

Fluctuation of v2--- indirect measurement via
v2{2} and v2{4} difference ---R. Snellings, QNP12CIPANP2012, 2/Jun/2012, St. Petersburg, Florida, USA

Univ. of Tsukuba, ShinIchi Esumi

19Variation of vn resultswith different pT range
for the global fit

PLB708 249-264

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Univ. of Tsukuba, ShinIchi Esumi

20vn{C2 global fit} ~ vn{2, |Δη|>1}

A. Adare, QM11

good agreement of vn even towards higher pTcoming from (low x high) pT combinations in C2
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Univ. of Tsukuba, ShinIchi Esumi

21Possible charge asymmetry signalfrom Local Parity Violation
S. A. Voloshin, Phys. Rev. C 70, 057901 (2004).

STAR Collaboration: Phys. Rev. Lett. 81, 251601 (2009)STAR Collaboration: Phys. Rev. C81, 054908 (2010)

P. Christakoglou, QM11

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pT dependence of theobserved asymmetry signal

P. Christakoglou, QM11

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B. Wyslouch (CMS), QM11

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J. Jia (ATLAS), QM11

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Univ. of Tsukuba, ShinIchi Esumi

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