[PPT] - IKF Helmholtz Research School Institut fr Kernphysik Frankfurt PowerPoint Presentation

SLIDE 1

Quarkonia Measurements with ALICE at the LHC

Frederick Kramer

for the ALICE Collaboration IKF, Goethe-Universit¨ at Frankfurt

Hadron 2011 Conference, Munich, June 16th, 2011

Helmholtz Research School

H-QM Quark Matter Studies

Institut für Kernphysik Frankfurt

IKF

SLIDE 2

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Introduction J/ψ in pp Collisions Differential Cross Sections Multiplicity Dependence J/ψ in Pb-Pb Collisions Nuclear Modification Factors

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 1 / 14

SLIDE 3

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Introduction

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 1 / 14

SLIDE 4

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Physics Motivation: J/ψ in Heavy-Ion Collisions Quark-Gluon Plasma (QGP): Deconfined state of strongly interacting matter

QGP induced effects: → AA

◮ Melting due to Debye screening ◮ Recombination of uncorr. Q¯

Q ⇈

◮ Thermal production (at LHC) ⇈

c c c c c c c c c c c c

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 2 / 14

SLIDE 5

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Physics Motivation: J/ψ in Heavy-Ion Collisions Quark-Gluon Plasma (QGP): Deconfined state of strongly interacting matter

QGP induced effects: → AA

◮ Melting due to Debye screening ◮ Recombination of uncorr. Q¯

Q ⇈

◮ Thermal production (at LHC) ⇈

c c c c c c c c c c c c

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 2 / 14

SLIDE 6

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Physics Motivation: J/ψ in Heavy-Ion Collisions Quark-Gluon Plasma (QGP): Deconfined state of strongly interacting matter

QGP induced effects: → AA

◮ Melting due to Debye screening ◮ Recombination of uncorr. Q¯

Q ⇈

◮ Thermal production (at LHC) ⇈

D D D D D D J/ψ J/ψ D D

c c c c c c c c c c c c

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 2 / 14

SLIDE 7

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Physics Motivation: J/ψ in Heavy-Ion Collisions Quark-Gluon Plasma (QGP): Deconfined state of strongly interacting matter

QGP induced effects: → AA

◮ Melting due to Debye screening ◮ Recombination of uncorr. Q¯

Q ⇈

◮ Thermal production (at LHC) ⇈

D D D D D D J/ψ J/ψ D D

c c c c c c c c c c c c

◮ Cold nuclear matter effects: → pA

◮ Nuclear absorption (small at LHC) ◮ Shadowing (depending on x) ⇈

◮ Direct Quarkonia production + feed down (J/ψ) → pp

Quarkonia in heavy-ion collisions - probe of deconfinement

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 2 / 14

SLIDE 8

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Physics Motivation: J/ψ in pp Collisions

CSM- CSM- (GeV/c)

T

p

5 10 15 20 25 30

α

1
0.8
0.6
0.4
0.2

0.2 0.4 0.6 0.8 1 CDF Data NRQCD [J.P.Lansberg: Phys. Lett. B 695 (2011) 149] [A.Abulencia: Phys. Rev. Lett. 99(13) (2007) 132001]

Competing models:

◮ Colour Singlet Model (CSM) ◮ Non-Relativistic QCD approach (NRQCD) ◮ Colour Evaporation Model (CEM) ◮ Polarization

parameter α = σT −2σL

σT +2σL

Elementary production mechanisms not well understood pp: crucial baseline for Pb-Pb

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 3 / 14

SLIDE 9

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

The ALICE Experiment ∼ 1000 members 116 institutes, 33 countries

J/ψ → e+e−

|y| < 0.9 pt > 0 TPC, ITS

J/ψ → µ+µ−

2.5 < y < 4.0 pt > 0 Muon Spectrometer

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 4 / 14

SLIDE 10

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

J/ψ in pp Collisions

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 4 / 14

SLIDE 11

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

J/ψ in pp Collisions - Invariant Mass Spectra at 7 TeV J/ψ → e+e−

2

Counts per 40 MeV/c

20 40 60 80 100 120

OS LS*1.25 =7 TeV s ALICE pp

)

2

(GeV/c

ee

m

1.5 2 2.5 3 3.5 4 4.5 5

20

20 40 60 80 100

OS-1.25*LS /dof=1.1)

2

χ MC (

[ALICE: arXiv:1105.0380]

◮ Background: Subtraction of

like-sign spectrum

◮ Signal: Bin counting

J/ψ → µ+µ−

)

2

(GeV/c

μμ

M 2 2.5 3 3.5 4 4.5 5

μμ

dN/dM 500 1000 1500 2000 2500 3000 3500 4000

=7TeV s pp,

ALICE Performance

20/5/2011

278 ± = 15090

ψ J/

N 1.0 MeV ± = 85.6

ψ J/

σ )= 2.5 σ S/B (3

◮ Fit of Crystal-Ball function

(signal) + 2 exponentials (background)

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 5 / 14

SLIDE 12

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Differential Cross Sections - 7 TeV dσ/dy

y

5
4
3
2
1

1 2 3 4 5

b) µ /dy (

ψ J/

σ d

1 2 3 4 5 6 7 8 9 10

e

+

ALICE, e

µ

+

µ ALICE, CMS LHCb

pen: reflected

=7 TeV s pp

d2σ/dptdy

(GeV/c)

T

p

2 4 6 8 10 12

b/GeV/c) µ dy (

T

/dp

ψ J/

σ

2

d

2

10

1

10 1

, |y|<0.9

e

+

ALICE e , 2.5<y<4.0

µ

+

µ ALICE CMS, |y|<1.2 ATLAS, |y|<0.75 LHCb, 2.5<|y|<4.0 =7 TeV s pp

[ALICE: arXiv:1105.0380], [CMS: arXiv:1011.4193], [ATLAS: arXiv:1104.3038], [LHCb: arXiv:1103.0423]

pt spectra in good agreement with other LHC experiments

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 6 / 14

SLIDE 13

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Differential Cross Sections - 2.76 & 7 TeV dσ/dy

y

5
4
3
2
1

1 2 3 4 5 b) µ /dy (

ψ J/

σ d 1 2 3 4 5 6 7 8 9

pen: reflected

ALICE preliminary

production ψ inclusive J/

(arXiv:1105.0380)

1

=7 TeV, L=3.9 nb s , pp

e

+

e (arXiv:1105.0380)

1

=7 TeV, L=13.3 nb s , pp

µ

+

µ

1

=2.76 TeV, L=1.1 nb s , pp

e

+

e

1

=2.76 TeV, L=20.2 nb s , pp

µ

+

µ

d2σ/dptdy

(GeV/c)

T

p 1 2 3 4 5 6 7 8 b / GeV/c) µ (

T

/dydp

ψ J/

σ

2

d

2

10

1

10 1

(arXiv:1105.0380)

1

=7 TeV, L=13.3 nb s

1

=2.76 TeV, L=20.2 nb s =7 TeV, CS+CO NLO s (M. Butenschoen et al., arXiv:1105.0820) =2.76 TeV, CS+CO NLO s (M. Butenschoen et al., priv. comm.)

ALICE preliminary pp, 2.5<y<4

Good agreement of d2σ/dptdy with NLO NRQCD calculations

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 7 / 14

SLIDE 14

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Inclusive J/ψ Production vs. Collision Energy

(TeV) s

1 10

b) µ /dy (

ψ J/

σ d

1 10

/dy, scaled to CDF data point

c c

σ line: d

c

= 2m

R

µ =

F

µ =1.2 GeV,

c

NLO (MNR), m

ALICE, |y|<0.9 ( CDF, |y|<0.6 PHENIX, |y|<0.35 preliminary )

1/2

s

2

10

3

10

4

10

2

> (GeV/c)

2 T

<p 2 4 6 8 10 12

production ψ Inclusive J/

<8 GeV/c

T

ALICE 2.5<y<4, p PHENIX 1.2<|y|<2.2 PHENIX |y|<0.35 HERAB E866 NA50 NA3 NA60 ALICE Preliminary [M.L.Mangano: Nucl. Phys. B373 (1992) 295]

◮ ALICE mid-rapidity data follows

trend of cross section vs. √s

◮ NLO pQCD dσc¯ c/dy prediction

scaled to match CDF data

◮

p2

t

extracted from fits to the

pt differential distributions

◮ Approximately logarithmic

increase with √s

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 8 / 14

SLIDE 15

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Multiplicity Dependence Y R

J/ψ: Yield in multiplicity bin over yield per inelastic pp collision

>

=0 η

| η /d

ch

<dN

=0 η

| η /d

ch

dN = η /d

R ch

dN 1 2 3 4 5 6 yield ψ yield over inclusive J/ ψ = J/

ψ J/ R

Y 1 2 3 4 5 6 7 8 9

ALICE Preliminary = 7 TeV s pp at

Global systematic error : 8%

ee (|y| < 0.9) → ψ J/ (2.5 < y < 4.0) µ µ → ψ J/

Approximately linear increase with charged particle density Indication for multiple parton interactions

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 9 / 14

SLIDE 16

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

J/ψ in Pb-Pb Collisions

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 9 / 14

SLIDE 17

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

J/ψ in Pb-Pb Collisions - Invariant Mass Spectra at 2.76 TeV J/ψ → e+e−

2

counts per 80 MeV/c

20 40 60 80 100 120 140 160

)

2

0.45 (2.88-3.20 GeV/c ± 0.07, Signif.: 4.8 ± 19.7, S/B: 0.34 ± S: 92

pposite sign (OS)

Bkgnd*0.09 ALICE Performance =2.76TeV

NN

s Pb-Pb, 12/05/2011 ee → ψ J/ | < 0.8

ψ J/

|y > 0

ψ J/ t

p

)

2

(GeV/c

ee

M

1.5 2 2.5 3 3.5 4 4.5

2

counts per 80 MeV/c

20
10

10 20 30 40 50 60 OS-0.09*Bkgnd /dof=1.1)

2

χ MC ( 5.1 / 12.6 Mevents (40-80%)

◮ Background: Track rotation

◮ Rotate one track by a

random angle around φ

◮ Signal: Bin counting

J/ψ → µ+µ−

)

2

Dimuon invariant mass (GeV/c 2 2.5 3 3.5 4 4.5 5 )

2

Events / ( 50 MeV/c 1 10

2

10

3

10

ALICE performance = 2.76 TeV

NN

s Pb+Pb, 19/05/2011 centrality bin : 40-80% 24 ± = 216

ψ J/

N 0.10 ± = 0.66

) σ 3 ± (

S/B 2.9 ± = 9.0

) σ 3 ± (

S+B S /nDoF = 1.39

2

χ

◮ Fit of Crystal-Ball function

(signal) + 2 exponentials (background)

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 10 / 14

SLIDE 18

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Inclusive J/ψ RAA RAA = YPb−Pb Ncoll · Ypp

◮ Bars: Statistical errors ◮ Boxes:

Centrality-dependent systematic uncertainties

◮ Filled box: Common

systematic uncertainties

◮ Not corrected for

feed-down from B decay Strong suppression already at peripheral collisions

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 11 / 14

SLIDE 19

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Inclusive J/ψ RAA

centrality 40-80% 20-40% 10-20% 0-10%

AA

R 0.2 0.4 0.6 0.8 1 1.2 1.4

>0 (preliminary)

T

= 2.76 TeV), 2.5<y<4, p

NN

s ALICE (Pb-Pb EPS09 (R. Vogt , priv. comm.)

RAA = YPb−Pb Ncoll · Ypp

◮ Bars: Statistical errors ◮ Boxes:

Centrality-dependent systematic uncertainties

◮ Filled box: Common

systematic uncertainties

◮ Not corrected for

feed-down from B decay Large uncertainties of shadowing prediction - pA data crucial

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 11 / 14

SLIDE 20

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Inclusive J/ψ RAA

*>

part

<N 50 100 150 200 250 300 350 400

AA

R 0.2 0.4 0.6 0.8 1 1.2 1.4

>0 (preliminary)

T

= 2.76 TeV), 2.5<y<4, p

NN

s ALICE (Pb-Pb >0 (arXiv:1103.6269)

T

= 0.2 TeV), 1.2<|y|<2.2, p

NN

s PHENIX (Au-Au >0 (nucl-ex/0611020)

T

= 0.2 TeV), |y|<0.35, p

NN

s PHENIX (Au-Au

coll

> is weighted by N

part

(*) ALICE <N

RAA = YPb−Pb Ncoll · Ypp

◮ Bars: Statistical errors ◮ Boxes:

Centrality-dependent systematic uncertainties

◮ Filled box: Common

systematic uncertainties

◮ Not corrected for

feed-down from B decay Less suppression in central events at LHC than at RHIC

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 11 / 14

SLIDE 21

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Inclusive J/ψ RCP RCP =

Nperiph.

coll

· Y cent.

Pb−Pb

Ncent.

coll

· Y periph.

Pb−Pb ◮ Systematic uncertainties

f the reference

(40-80%) propagated to the ratio Weak centrality dependence of RCP

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 12 / 14

SLIDE 22

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Inclusive J/ψ RCP

centrality 40-80% 20-40% 10-20% 0-10% normalized to 40-80%

CP

R 0.2 0.4 0.6 0.8 1 1.2

= 2.76 TeV

NN

s Pb-Pb >0 (preliminary)

T

ALICE, 2.5<y<4, p >6.5 GeV/c (arXiv:1012.5419)

T

ATLAS, |y|<2.5, p

RCP =

Nperiph.

coll

· Y cent.

Pb−Pb

Ncent.

coll

· Y periph.

Pb−Pb ◮ Systematic uncertainties

f the reference

(40-80%) propagated to the ratio RCP of most central collisions larger at forward rapidities (ALICE) than at central rapidity & high pt (ATLAS)

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 12 / 14

SLIDE 23

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Inclusive J/ψ RCP

centrality 40-80% 20-40% 10-20% 0-10% normalized to 40-80%

CP

R 0.2 0.4 0.6 0.8 1 1.2

= 2.76 TeV

NN

s Pb-Pb >0 (preliminary)

T

ALICE, 2.5<y<4, p >0 (preliminary)

T

ALICE, |y|<0.8, p >6.5 GeV/c (arXiv:1012.5419)

T

ATLAS, |y|<2.5, p

RCP =

Nperiph.

coll

· Y cent.

Pb−Pb

Ncent.

coll

· Y periph.

Pb−Pb ◮ Systematic uncertainties

f the reference

(40-80%) propagated to the ratio Challenging analysis in e+e− at mid-rapidity: Still large errors

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 12 / 14

SLIDE 24

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Summary & Outlook

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 12 / 14

SLIDE 25

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Summary

◮ pp collisions:

◮ ALICE has measured the inclusive J/ψ production in √s = 7 and

2.76 TeV pp collisions in e+e− and µ+µ−

◮ Results are in good agreement with NLO NRQCD calculations ◮ The inclusive J/ψ yield shows a linear increase with the multiplicity

◮ Pb-Pb collisions:

◮ The inclusive J/ψ RAA and RCP have been presented as a function

f collision centrality

◮ J/ψ RAA larger at LHC (2.5 < y < 4.0) than at RHIC in

1.2 < y < 2.2; closer to RHIC at |y| < 0.35

◮ J/ψ RCP larger at ALICE (2.5 < y < 4.0) than at ATLAS (|y| < 2.5,

pt> 6.5GeV ) in central collisions

◮ Unique at LHC for ALICE: pJ/ψ t

reach down to 0 GeV/c

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 13 / 14

SLIDE 26

Introduction J/ψ in pp Collisions J/ψ in Pb-Pb Collisions Summary & Outlook

Outlook

◮ Polarization measurements ◮ Measurement of secondary J/ψ ◮ Transition Radiation Detector as trigger and to improve PID

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 27

Backup

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 28

Backup - J/ψ from B Decay cτ ∼ 500µm → likely to have a displaced vertex B fraction: Simultaneous fit

f inv. mass + pseudo

proper decay length x = Lxy MJ/ψ pt

m) µ ) ( ψ (J/

T

)/p ψ *M(J/

xy

L

1000
500

500 1000 1500 m µ Entries/40

1

10 1 10

2

10

data total fit ψ prompt J/ ψ secondary J/ background

ALICE performance s = 7 TeV √ pp 18/05/2011

) > 1.3 GeV/c ψ (J/

T

p

e

+

e → ψ J/

| < 0.9 η |

◮ Measurement possible at central rapidity due to excellent impact

parameter resolution (σrφ < 75µm for pt > 1GeV/c)

◮ First estimation ongoing, high statistics sample collected in 2011

should allow for a precise measurement

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 29

Backup - J/ψ Polarization

◮ Important observable to test theory ◮ 2010 7 TeV pp statistics allow determination of full angular

distribution of J/ψ decay muons

◮ Expected statistical error of the polarization parameter < 0.2 for 3

pt bins

)

2

(GeV/c

µ

+ µ

M 1.5 2 2.5 3 3.5 4 4.5 5

µ

+ µ

dN/dM 1 10

2

10

| < 0.15

HE

θ 0.00 < |cos

< 8 GeV/c

T

3 < p = 7 TeV s p+p at ALICE Performance 12/04/2011 )

2

(GeV/c

µ

+ µ

M 1.5 2 2.5 3 3.5 4 4.5 5

µ

+ µ

dN/dM 1 10

2

10

| < 0.30

HE

θ 0.15 < |cos

)

2

(GeV/c

µ

+ µ

M 1.5 2 2.5 3 3.5 4 4.5 5

µ

+ µ

dN/dM 1 10

2

10

| < 0.45

HE

θ 0.30 < |cos

)

2

(GeV/c

µ

+ µ

M 1.5 2 2.5 3 3.5 4 4.5 5

µ

+ µ

dN/dM 1 10

2

10

| < 0.60

HE

θ 0.45 < |cos

)

2

(GeV/c

µ

+ µ

M 1.5 2 2.5 3 3.5 4 4.5 5

µ

+ µ

dN/dM 10

2

10

| < 0.80

HE

θ 0.60 < |cos

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 30

Backup - Contributions to J/ψ Yield

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 31

The ALICE Experiment ∼ 1000 members 116 institutes, 33 countries

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 32

The ALICE Experiment Time Projection Chamber

J/ψ → e+e−

|y| < 0.9 pt > 0

p (GeV/c)

t

Δp /p

t t

1 10 10

2

10

1

◮ Main tracking device ◮ PID of charged particles

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 33

The ALICE Experiment Inner Tracking System

J/ψ → e+e−

|y| < 0.9 pt > 0

[GeV/c]

t

p 1 10 m] μ resolution [ r d 50 100 150 200 250 300

Data MC, residual misal.

(LHC10c period)

ALICE Performance

30/09/2010

◮ 3 × 2 layers of silicon

detectors: pixel, drift, strip

◮ Primary + secondary

vertices

◮ Improve momentum

measurement

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 34

The ALICE Experiment Forward Muon Spectrometer

J/ψ → µ+µ−

2.5 < y < 4.0 pt > 0

◮ Absorber

+ beam shield + filter protect from hadrons

◮ 10 plane tracking system ◮ 4 plane trigger system ◮ Dipole magnet: momentum

determination

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 35

The ALICE Experiment V0

◮ Minimum bias trigger

together with the ITS

◮ V0 amplitude: Centrality

selection in Pb-Pb

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 36

J/ψ in pp Collisions - Run Statistics Triggers:

◮ e+e−: minimum bias interaction trigger ◮ µ+µ−: forward muon in coincidence with minimum bias trigger

Results are based on: Energy (TeV) LHC period Integrated Luminosity (nb−1) J/ψ → e+e− J/ψ → µ+µ− 7 2010 3.9 15.6 2.76 2011 1.1 20.2

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 37

J/ψ in Pb-Pb Collisions - Run Statistics Trigger:

◮ Minimum bias interaction trigger

Results are based on: Energy (TeV) LHC period Integrated Luminosity (µb−1) 2.76 2011 2.7 Centrality selection:

◮ Based on a geometrical Glauber-model fit to the V0 amplitude

VZERO Amplitude (a.u.)

2000 4000 6000 8000 10000 12000 14000 16000 18000 20000

Events

1

10 1 10

2

10

3

10 = 2.76 TeV

NN

s Pb-Pb at Data Glauber fit

part

+ (1-f)N

coll

NBD x f N

=1.202 κ =29.003, µ f=0.194,

0-5% 5-10% 10-20% 20-30% 30-40% 40-50% 50-60%

500 1000 10

2

10 80-90% 70-80% 60-70%

ALICE Performance

7/05/2011

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 38

Backup - Cross Section vs. Energy

◮ High precision data needed ◮ Data in new energy regime further

constrains models

◮ pp data: crucial baseline for AA

(GeV) s 10 100 1000 10000 (mb) σ

4

10

3

10

2

10

1

10 1 10

2

10

3

10

4

10

5

10

6

10

geom

σ

NN

Pb-Pb hard cross sections

2

A × (NLO)

pp

σ =

PbPb

σ

c c b b

ψ J/

>100 GeV

T

Jet E

W

Z t t

SPS RHIC LHC

Υ

[D.d’Enterria: Nucl. Part. Phys. 35(10) (2008) 104039]

LHC will deliver excellent statistics for quarkonia measurements

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 39

Backup - Relative Yield, Multiplicity

tracklets

N

/

tracklets

N

1 2 3 4 5 6

Probability

4

10

3

10

2

10

1

10 LHC10b LHC10c LHC10d LHC10e

ALICE Performance =7 TeV s pp 13.05.2011

| < 1.6

tracklet

|

Relative Yield

Y R

J/ψ = Y bin

J/ψ

Y inel

J/ψ =

Nbin

J/ψ/Nbin CINT 1B

Ninel

J/ψ /Ninel

ch

N

10 20 30 40 50 60 70 80

Tracklets

N

10 20 30 40 50 60 70 80

Entries

1 10

2

10

3

10

4

10

ALICE Performance Monte Carlo Simulations 12.05.2011

| < 1.6

|

Relative Multiplicity

dNR

ch/dη = dNch/dη|η=0 dNch/dη|η=0

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 40

Backup - Corrections pp

[GeV/c]

T

p

1 2 3 4 5 6 7 8 9

Acceptance x efficiency

0.05 0.1 0.15 0.2 0.25

unpolarized J/ uncertainty in Collins-Soper frame uncertainty in Helicity frame

ALICE Performance 06/10/2010 (GeV/c)

T

p 1 2 3 4 5 6 7 8 0.1 0.2 0.3 0.4 0.5 0.6 = 0

HE

= +/-1

HE = 7 TeV s + X, J/ p+p

ALICE Performance

8/10/2010 PWG3-MUON-021-101008

J/ψ → e e

+ -

J/ψ → μ μ

+ -

Acceptance x efficiency

PWG3-Jpsi2e-007-101006

Analysis in e+e− (10.0%)

1. Kinematical acceptance

◮ |yJ/ψ| < 0.9 ◮ |ηe+,e−| < 0.9 ◮ pe+,e−

t

> 1.0 GeV/c

2. Reconstruction efficiency
3. Particle identification
4. Mass integration limits

Analysis in µ+µ− (32.9%)

1. Kinematical acceptance

◮ −4.0 < yJ/ψ < −2.5 ◮ pµ+,µ− > 4.0 GeV/c

2. Reconstruction efficiency

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 41

Backup - Partial Efficiencies pp

[GeV/c]

T

p

1 2 3 4 5 6 7 8 9

efficiency

0.2 0.4 0.6 0.8 1

kinematics tracking (with SPD any) tracking (with SPD first) particle identification

ALICE Performance 06/10/2010

PWG3-Jpsi2e-005-101006

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 42

Backup - Systematic Error Estimation pp Channel e+e− µ+µ− Trigger efficiency 0% 4% Acceptance input 1% 2% Reconstruction efficiency 11% 3% Signal extraction 8.5% 7.5% R factor 0% 3% Luminosity 8% Branching ratio 1% Total sys. error 16.1% 12.6% Polarization α = −1 α = 1 α = −1 α = 1 Collins-Soper +19%

13%

+31%

15%

Helicity +21%

15%

+22%

10%

◮ Largest contribution: (yet) unknown polarization

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 43

Backup - Systematic Error Estimation Pb-Pb Source e+e−centrality common 0-10% 10-20% 20-40% 40-80% NJ/psi 19% 14% 17% 14% NJ/psi/N 40−80%

J/psi

12% 8% 7% Acceptance input 3% Tracker efficiency 4% 2% 1% 0% 5% Trigger efficiency 4% Reconstruction eff. 2% Branching ratio 1% Cross section 13% TAA 4% 4% 4% 6% TAAi / TAA

40−80%

6% 5% 4% Total for RAA 20% 15% 17% 15% 15% Total for RCP 14% 10% 8%

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 44

Backup - Polarization Reference Frames

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 45

Backup - Polarization Reference Frames Characterization of the Quark-Gluon Plasma

◮ Direct Quarkonia production

+ feed down (J/ψ) → pp

◮ Cold nuclear matter effects: → pA

◮ Nuclear absorption

(small at LHC)

◮ Shadowing (depending on x) ⇈

QGP induced effects: → AA

◮ Melting due to Debye screening ◮ Recombination of uncorr. Q¯

Q ⇈

◮ Thermal production (at LHC) ⇈

=0 η

| η dN/d

100 200 300 400 500 600 700 800

(CNM)

AA

/ R

AA

R

0.4 0.6 0.8 1 1.2 1.4

Narrow boxes: correlated sys Wide boxes: CNM baseline sys EKS98 CNM baseline PHENIX Au+Au y=0 NA60 In+In NA50 Pb+Pb

[N.Brambilla: arXiv:1010.5827v3/hep-ph]

RAA =

Y J/ψ

Pb−Pb

Ncoll·Y J/ψ

pp Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 46

Fit to pt Spectra dσ dpt ∼ pt

1 +
pt

p0

2x (1)

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14

SLIDE 47

Physics Motivation: Quark-Gluon Plasma

Big Bang

u

?

I n fl a t i

n

G U T Q G P N u c l e i A t

m

s T

d

a y 10 s 10 10

37

28 15

t T (K) E (GeV) 1.2 x 10 y 2.7 2.3 x 10

10

13

10 s 10 10

10

15 2

10 s 10 10

5

12

1

3 x 10 y 3 x 10 3 x 10

5 3

10

S t a r s 10 y 15 10

9

12

d s e u d s Z t b c W g μ γ g e τ ν γ e u d s t b c g g

before collision initial state QGP freeze out fireball

Frederick Kramer Quarkonia Measurements with ALICE at the LHC 14 / 14