44
John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Embed Size (px)

Citation preview

Page 1: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

The Relativistic Heavy Ion Frontier at the LHC

Tamura Symposium

Page 2: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

The Quark-Gluon Plasma – Present View from RHIC

• Large > c (T > Tc) system – Sufficient for QGP formation – NOT hadrons

Particle ratios fit by thermal model T = 177 MeV ~ Tc (lattice QCD)

• Large volume of quarks & gluons (hydrodynamics) – NOT just q & g scattering

Large elliptic & radial flow large pressure gradients

Ultra-low shear viscosity “nearly-perfect” fluid flow

• Dynamics of quarks and gluons – QGP EoS, quark coalescence – NOT hadrons

Flow develops at quark level & depends upon constituent quark masses

• Strongly-coupled quarks and gluons – NOT Weakly-interacting QGP (as thought)

Large parton energy loss

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 3: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Simple Expectations – Heavy Ion Interactions at LHC

QGP (fm/c)

(GeV/fm3)

T / Tc

√sNN (GeV) factor 28

2-4

5

1.9

200

RHIC

≤ 2

3

1.1

17

LHCSPS

5500

3.0 - 4.2 hotter

15-60 denser

> 10longer-lived

RHIC and LHC:

Cover 2 – 3 decades of energy (sNN ~ 20 GeV – 5.5 TeV)

To determine the properties of hot QCD at T ~ 150 – 600 MeV

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 4: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Geometry of Heavy Ion Collisions at LHC

General Orientation

Hadron masses ~ 1 GeV

Hadron sizes ~ fm

LHC Heavy Ion Collisions

Ecm = 5.5 TeV per nn-pair

Total Ecm = 1.54 PeV

Lead nucleusdiameter ~ 14 fm

= 2,700 (Lorenz contracted)

~ (14 fm/c) / < 0.01 fm/c

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 5: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Why Heavy Ions at the LHC?

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov.

2008

•Expect different timescales, shorter interaction times, higher energy (T) !

Does system still equilibrate rapidly?

Thermal model still applies? T still ~ Tc (lattice QCD)?

Does it flow?

Elliptic Flow change? v2 still saturated? More or less v2?

Is the QGP still strongly- (or weakly-) coupled?

Liquid? More like a gas? No longer “nearly-perfect” fluid flow?

Impact on energy loss!!

• Understand parton energy loss! – What are the microscopic processes?

mass and flavor dependence?

use high pT jets & tag heavy quark jets

• Understand response of the medium!

Strongly interacting quarks and gluons away-side response?

use punch-through & associated jet

• Color screening of the medium!

Deconfinement? (compare LQCD), initial T, other effects J/ & Y states

Page 6: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

LHC Heavy Ion Programs

Heavy Ion Data-taking

Pb + Pb at sNN = 5.5 TeV

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 7: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

ALICE – the Heavy Ion Experiment

ALICE is a versatile, heavy ion detector at the LHC

Overview:

Soft Probes – “ala RHIC” • Expansion dynamics different from RHIC• Soft physics measurements ala RHIC

+ extended PID• Day 1 physics +

Hard Probes – Jet Quenching• Jets, pi-zeros, leading particles to large pT

Hard Probes – Heavy Quarks• Displaced vertices (Do K- +) from TPC/ITS• Electrons in Transition Radiation Detector (TRD)

Hard Probes – Quarkonia• J/, , ’ (excellent), ’’(2-3 yrs), ’ ???

US Members: Cal. St. U. – San Luis Obispo Creighton University University of Houston Lawrence Berkeley Nat. Lab Lawrence Livermore Nat. Lab Oak Ridge National Lab Ohio State University Purdue University University of Tennessee Wayne State University Yale University

Affiliated US Member: University of Texas – Austin

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 8: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

The ALICE Experiment

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 9: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

CMS Heavy Ion Program

Overview:

CMS has a broad heavy ion physics program

- precision tracking < 2.5

- muon identification < 2.5

- high-res calorimetry < 5

- forward coverage

CMS expects to excel at

- photon-tagged jet measurements

(FF modifications)

- quarkonium measurements

US Members: University of California at Davis University of Illinois at Chicago University of Iowa University of Kansas Los Alamos National Laboratory University of Maryland MIT University of Minnesota Rice University Vanderbilt University

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 10: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

ATLAS Heavy Ion Program

Overview:

ATLAS has a broad heavy ion physics program- excels at jet and photon measurements

Jets- reconstruct jets in a large kinematical range

ET > 40 GeV and |η|<5- perform key fragmentation measurements- jet shape and FF modifications- multi-jet studies

Photons- isolate / measure photons in large range, ET > 10 GeV and |η|<2.5- unique calorimeter design allows additional rejection beyond isolation

US Members: Brookhaven National Lab Columbia University Iowa State University Stony Brook University

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 11: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Heavy Ion Physics at the LHCLHC Heavy Ions –

• expectations based on pQCD predictions & RHIC results• a lesson from RHIC – guided by theory + versatility + “expect the unexpected”

Soft Physics (pT ≤ 2 GeV/c) with heavy ions at LHC – • smooth extrapolation from SPS RHIC LHC?

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Particle Multiplicities

LHC

Page 12: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Heavy Ion Physics at the LHCLHC Heavy Ions –

• expectations based on pQCD predictions & RHIC results• a lesson from RHIC – guided by theory + versatility + “expect the unexpected”

Soft Physics (pT ≤ 2 GeV/c) with heavy ions at LHC – • smooth extrapolation from SPS RHIC LHC?• expansion dynamics different (initial state, flow, HBT, evolution of T, strange/charm/beauty)

x

z

y

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 13: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Heavy Ion Physics at the LHCLHC Heavy Ions –

• expectations based on pQCD predictions & RHIC results• a lesson from RHIC – guided by theory + versatility + “expect the unexpected”

Soft Physics (pT ≤ 2 GeV/c) with heavy ions at LHC – • smooth extrapolation from SPS RHIC LHC?• expansion dynamics different (initial state, flow, HBT, evolution of T, strange/charm/beauty)

Elliptic Flow

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 14: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Probing Hot QCD Matter with Hard Probes

hadrons

leading particle

hadrons

leading particle

parton energy loss: modification of jets and leading particles & jet-correlations

jets

jets

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 15: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Parton Energy LossJet Quenching

(Parton energy-loss, parton density, medium response)What happens to the radiation?

Egluon > Equark, m=0 > Equark, m>0

How does E depend on type of parton?

• Jets, 0, leading particles to large pT

• Modification of fragmentation• Medium response to E deposition - dissipation on near- and away-side

EGluon radiation

Collision E-loss

How does parton lose energy?

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

q = 2 / ^

q ~

Page 16: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Significant increase in hard cross sections

(pT or mass > 2 GeV/c) at LHC – large pT /total~ 2% at SPS

50% at RHIC

98% at LHC• “real” jets, large pT processes

• abundance of heavy flavors• probe early times, calculable

bb (LHC ) ~ 100 bb (RHIC)

cc (LHC) ~ 10 cc (RHIC)

Rat

e

Hard Probes with LHC Heavy Ions

Page 17: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Example: High PT Suppression – RHIC and LHC

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Courtesy: B. Wyslouch and CMS

Page 18: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Hard Probe Capabilities of ALICE

ALICE physics capabilities:- Fast trigger on jets (EMCal)

- Good discrimination (EMCal, PHOS)

- Electron/hadron disc. (TRD, EMCal)

Hard Probes statistics in ALICE:

104/year in minbias Pb+Pb:

inclusive jets: ET ~ 200 GeV

dijets: ET ~ 170 GeV

: pT ~ 75 GeV

inclusive : pT ~ 45 GeV

inclusive e: pT ~ 30 GeVThanks – Peter Jacobs

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 19: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Jet-finding - Learning from the Tevatron & RHIC

p + p experience (CDF)

- most of energy within cone of

R = (2 + 2) < 0.3

p T /

cell

(GeV

/c)

200 GeV Au + Au central collision (STAR)

Ejet = 21 GeVAu + Au experience (STAR) - HI Background

Must suppress “soft” background:

- small jet cones R = 0.3-0.4

- pT cut: pT > 1 – 2 GeV/c

- EbyE out-of-cone background energy

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 20: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Example of Anticipated Jet Measurements

dN /d = 2700 Top 0.5% σAA

Reconstructed spectra not corrected for efficiency or energy resolution.

Courtesy: B. Cole and ATLAS

Page 21: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Jet Quenching in CMS at the LHC

Jet spectra up to ET ~ 500 GeV (Pb-Pb, 0.5 nb-1, HLT(triggered)

Courtesy: C. Roland and CMS

Page 22: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Measuring the PbPb Fragmentation Function

Jet energy determination:

Rc=0.4 pT > 1 GeV/c

jet

More studies of background are needed & underway!

J. Putschke, ECT 2008

Charged particles for FF

Rc=0.7 pT > 0 GeV/c

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 23: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Tagging Jets with Photons for Parton Energy

Reconstruct the jet : Particles around leading particle inside acone R = 0.3…

Search for & identify prompt photon with largest pT

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Search for leading particle: - leading ~ 180º

e.g. Eleading > 0.1 E

Page 24: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

- Jet Simulations in CMS at the LHC

Select away-side jet with (, jet) > 172o, ||< 2 and ET (jet) > 30 GeV

• ET (jet) cut reduces false rate to ~ 10% (Otherwise, no use of jet energy)

• Jet finding efficiency increases sharply from 30 - 100 GeV jet ET

Quenched Pb+Pb

Fal

se r

ate

frac

tio

n (

%)

Jet-

fin

din

g e

ffic

ien

cy

Courtesy: C. Roland and CMS

Page 25: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

ET, > 70GeV

ET, > 100GeV

QuenchedUnquenched

QuenchedUnquenched

Fragmentation Functions in CMS

Courtesy: C. Roland and CMS

Page 26: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Heavy Flavor RAA at RHIC & LHC!

Uncertainties at RHIC (bands > ±0.1 ) - perturbative production of c and b jets - ratio of c to b jets is very uncertain.

Wicks & Gyulassy, Last Call for LHC Predictions

RHIC LHC

Heavy quark electrons at RHIC D & B mesons at LHC

LHC: - Different slopes of spectra

little effect on RAA results.

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 27: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Charm and Beauty E-Loss in ALICE

Displaced vertices (Do K- +) from trackingElectrons from Transition Radiation Detectors, EM Cal’s….1 nominal year: 107 central Pb-Pb events, 109 pp events

errors: statistical (bars) and systematic (bands)

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Sensitive to color charge

Sensitive to mass dep.E-loss calc.: Armesto, Dainese, Salgado, Wiedemann

Page 28: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

B-jet Physics

Quark vs gluon E-loss in medium

B-jets - pure sample of quark jets

WHDG, arXiv:nucl-th/0512076

Measure B-jet Fragmentation Fctn

- harder fragmentation of b-quark

(higher <z> )

- Ejet measured more precisely

- Better measurement of FF

Fragmentation Function of b-quark

Wicks et al, nucl-th/0512076

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 29: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

ALICE B-jet Physics WHDG, arXiv:nucl-th/0512076

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 30: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

A Test of “Theories” in the Future from Heavy Flavors at RHIC & LHC?

W. Horowitz, M. Gyulassy, arXiv:0804.4330v1

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 31: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

QuarkoniaHeavy Quarks (mass/color dependence of parton energy-loss)

• Displaced vertices (Do K- +) from tracking• Electrons from Transition Radiation Detectors, EM Cal’s….

Quarkonia (initial temperature, Debye color screening, recombination)

• J/, , ’ (excellent), ’’(few yrs), ’ (difficult)

Color Screening

cc

Color screening of cc pairresults in J/ (cc) suppression!

Confined

Deconfined

r

V(r)

Bound state (e.g. J/)

Quarkonium dissociation when rDebye ~ 1/(sT) < rqq

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 32: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

QuarkoniaHeavy Quarks (mass/color dependence of parton energy-loss)

• Displaced vertices (Do K- +) from tracking• Electrons from Transition Radiation Detectors, EM Cal’s….

Quarkonia (initial temperature, Debye color screening, recombination)

• J/, , ’ (excellent), ’’(few yrs), ’ (difficult)

John Harris (Yale U.) US LHC User’s Meeting, 24 October 2008

T/TC 1/r [fm-1]

(1S)

J/(1S)

c(1P)

’(2S)

b’(2P)

’’(3S)

Karsch hep-lat/0502014v2

Measure melting order of cc: ’, c, J/bb: ’’, ’,

Page 33: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Quarkonia in CMS at the LHC

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 34: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

At LHC:

Is the QCD phase diagram feature-less at 1 – 4 Tc?

What happens as we go up in T (e.g. strongly-coupled)?

Are there new phenomena?

What’s the range of theoretical validities (non-pQCD, pQCD, strings)?

Measure/understand parton energy loss at the fundamental level

Establish flavor (gluon and quark mass) dependence

Use jets and/or photons to establish hard-scattered parton energy

Jet modifications - longitudinal & transverse “heating”

Medium response to jet-heating (near- and away-side)

Measure/use open charm and beauty decays (also as jet-tags)

cc and bb states (Ti, screening/suppression, enhancement?)

Direct Photon Radiation?

Developments in theory (lattice, hydro, parton E-loss, string theory…)

“the next frontier!”

Quark-Gluon Plasma at LHC – Today’s Perspective

Page 35: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

The End

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Page 36: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium
Page 37: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale U.) BNL Physics Seminar, 2 September 2008

B.Hippolyte Hot Quarks 2008 - Estes Park

Material Budget

ALICE Ideal Reconstruction and identification low pT : lowest material

budget

Cumulative mid-rapidity material budget for ALICE, ATLAS and CMS

ALICE x/X0 (%) ATLAS x/X0 (%) CMS x/X0 (%)

Beam pipe 0.26 Beam pipe 0.45 Beam pipe 0.23

Pixels (7.6 cm) 2.73 Pixels (12 cm) 4.45 Pixels (10.2 cm) 7.23

ITS (50 cm) 7.43 SCT (52 cm) 14.45 TIB (50 cm) 22.23

TPC (2.6 m) 13 TRT (1.07 m) 32.45 TOB (1.1 m) 35.23

Page 38: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Calorimeter Comparisons

Page 39: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) LNF Spring School, Frascati 12 – 16 May 2008

ALICE Detectors & Acceptance

(charged particles)

µ arm

central barrel -0.9 < < 0.9• = 2 tracking, PID (TPC/ITS/ToF)• single arm RICH (HMPID)• single arm e.m. cal (PHOS)• jet calorimeter (proposed EMCal)

forward muon arm 2.4 < < 4• absorber, 3 T-m dipole magnet10 tracking + 4 trigger chambers

multiplicity detectors -5.4 < < 3• including photon counting in PMD

trigger & timing detectors• 6 Zero Degree Calorimeters• T0: ring of quartz window PMT's• V0: ring of scint. Paddles

Page 40: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) Winter Workshop on Nuclear Dynamics, South Padre Is. TX – 4/8/08

ALICE Jet Trigger Yields in an LHC Pb + Pb Year

Jet yield in 20 GeV bin

Large gains due to jet trigger

Large variation in statistical reach for different reference systems

Includes acceptance, efficiency, dead time, energy resolution

Page 41: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

04/21/23

Particle Charmonia +- Charmonia e+e- Bottonia +- Bottonia e+e-

Bkg-subtr. mass plot

acc. -4 < < -2.5 || < 0.9 -4 < < -2.5 || < 0.9

M res. 65 MeV 35 MeV 90 MeV 90 MeVS /

(S+B)

(1 mo.) J/ 150, ’ 7 J/ 245

30, ’ 12,

’’ 8 21, ’ 8

Perf. , ’ , ’ , ’,’’ , ’, no ’’pt J/ 0-20 GeV J/ 0-10 GeV 0-8 GeV --

Quarkonia PerformancedNch/dy = 4000 in central Pb-Pb

Page 42: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Charm and Beauty E-Loss : RAA

D0 K

1 year at nominal luminosity(107 central Pb-Pb events, 109 pp events))

B e + X

D+ K

mC = 1.2 GeV

mC = 0

mb = 4.8 GeV

B eE-loss calc.: Armesto, Dainese, Salgado, Wiedemann

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008

Sensitive to color chargeSensitive to mass

Page 43: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

Andreas Morsch, Quark Matter 2008 44

-Jet Correlations

• Dominant processes in pp– g + q → + q (Compton)– q + q → + g (Annihilation)

• -jet correlations– E Ejet

– Opposite direction– Direct photons are not perturbed by

the medium

min max

IP

PHOS

EMCal

TPC

Direct are likely to be produced isolated. Two parameters define isolation:

Cone size RpT threshold, candidate isolated if:

No particle in cone with pT > pTthres

orpT sum in cone, pT < pT

thres

• Identification– Time of flight– Charged particle veto– Shower shape

Page 44: John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008 The Relativistic Heavy Ion Frontier at the LHC Tamura Symposium

John Harris (Yale) Gordon Research Conference, Nuc. Chem 2008

The Future of RHI‘s at the LHC:

Dedicated HI experiment - ALICE

Two pp experiments with HI programs:

ATLAS and CMS

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov. 2008