ALICE potential for Heavy Flavour Physics

1
ALICE potential for Heavy Flavour Physics

• Gines MARTINEZ-GARCIA
  for the ALICE collaboration
• Subatech, Nantes, France

2
Physics Motivations

• Probing and characterizing the quark gluon plasma
  (QGP) in Heavy-Ion collisions
• Energy loss of Heavy Quarks (HQ) in hot and high
  density medium formed in AA central collisions
  quark coupling and dead-cone effect
• Brownian motion and coalescence of low pT HQ in
  the QGP
• Dissociation (and regeneration) of quarkonia in
  hot QGP
• Heavy flavour physics in pp collisions small x
  physics, pQCD, HQ fragmentation functions, gluon
  shadowing, Quarkonia production mechanism
  

Motivations
3
Heavy Quarks in HIC at LHC

• Small xBj (10-3 10-5)
• DtQ 0.04 0.15 fm/c
• DtQ ltlt tQGP ltlt tQ
• Shadowing / Saturation
• HQ energy loss in QGP
• HQ thermalization (low pT)

L.O.
HQ _at_LHC
4
Charmonia in HIC at LHC
RHIC
SPS
LHC
PLB637 75 (2006)

• Melting of Y and c at SPS and RHIC, and melting
  of J/Y at LHC?
• Magic cancellation between J/Y suppression and
  J/Y regeneration?

22 (39) of J/Y (Y) from open beauty meson
decays.
HQ _at_LHC
5
Bottomonia in HIC at LHC
CUSB Detector(Cornell)

• First measurement of Bottomonia.
• Regeneration is expected to be small at LHC.
• ?(1S) melts only at LHC.
• ?(2S)/?(1S) as a function of centrality and pT.

Dm(3S-2S) 332 MeV/c2
45 (30) of feed-down from higher resonances for
?(1S) (?(2S))
HQ _at_LHC
6
ALICE Capabilities

• ALICE combines electronic, muonic and hadronic
  channels
• ALICE covers down to pT 0 for quarkonia and
  open charm
• ALICE covers central (hlt0.9) and forward
  (-4.0lthlt-2.5) regions
• High precision vertexing in the central barrel

ALICE
7
Physics Analysis

• Hadronic decays
• D0?K-p, D-?K-p-p-, Ds?K K, Ds?f p,
• Leptonic decays
• Single lepton analysis
• Open charm, open beauty, electro-weak bosons
• Invariant mass analysis of lepton pairs
• BB, DD, BDsame, J/Y, Y, ? family, B ?J/Y
  anything
• Multi-lepton analysis
• BB ? J/y m ? m m m

ALICE
8
D0 ? K-? channel

• High precision vertexing, better than 100 mm
  (ITS)
• High precision tracking (ITSTPC)
• K and/or p identification (TOF).

F. ANTINORI, A. DAINESE et al.
109 pp 108 pPb 107 PbPb
107 central PbPb
D ?Kp
Open Flavours
9
D- ? K-?? channel

• Building Kpp triplets from Kp pairs (as in D0
  analysis)
• Secondary vertex quality lt180mm, pointing
  angle gt0.995 and dist to primary vertex gt1900
  mm

QM06 Poster E. BRUNA, F. PRINO et al.
Scaled to 107central PbPb
PbPb central Significance for
dNch/dy6000 40 for dNch/dy2000
90
Open Flavours
10
Open Beauty from single e

• Electron Identification (TRDTPC)
• High precision vertexing (ITS)
• Subtraction of the open charm contribution.

F. ANTINORI, M. LUNARDON, R. TURRISI et al.
107 central PbPb
Open Flavours
11
Open Beauty from m and mm
QM06 Poster N. BASTID, Ph. CROCHET, R. GUERNANE
et al.
Single Muons
BDsame
BB
5 central PbPb
Open Flavours
12
Energy Loss Physics
Charm Production Quark versus gluon Energy
Loss Lower quark coupling
Beauty production Mass dependence of Energy
Loss Dead cone effect
ALICE PPR Vol.2. J. Phys. G Nucl. Part. Phys. 32
1295
Open Flavours
13
Quarkonia in ALICE
J/Y
J/Y
Di-electron channel
hlt0.9
-4.0lthlt-2.5
?
?
Di-muon channel
-4.0lthlt2.5
Until pT 0
hlt0.9
Quarkonia
14
Quarkonia in the electron channel

• Electron Identification (TRDTPC)
• Tracking ITSTPCTRD
• 2x108 central PbPb events (no e-trigger).

QM06 Poster W. SOMMER, C. BLUME et al.
10 central PbPb dNch/dy 3000
Quarkonia
15
Quarkonia in the muon channel
PbPb cent, 0 fmltblt3 fm
F. GUERIN, S. GRIGORYAN et al.
Yields for baseline

• ?(1S) ?(2S) 0-8 GeV/c
• J/Y high statistics 0-20 GeV/c
• Y poor significance
• ?(3S) ok, but 2-3 run needed.

Quarkonia
16
J/y??? (polarization) in pp
R.. ARNALDI, D. STOCCO, E. SCOMPARIN, E.
VERCELLIN et al.
agt0 Transverse a0 alt0 Longitudinal
Possible with gt50000 J/y Error below 10 Bgk
contribution small Systematics in the J/y
acceptance due to polarization ignorance bellow
10.
pp at 14 TeV Nominal run 3x106 J/y (mm) pT
0-20 GeV/c
Quarkonia
17
Suppression Scenarii

• Suppression-1
• Tc 270 MeV
• TD/Tc1.7 for J/Y
• TD/Tc 4.0 for ?.
• Suppression-2
• Tc190 MeV
• TD/Tc1.21 for J/Y
• TD/Tc 2.9 for ?.

Ph. CROCHET, F, GUERIN, R. GUERNANE, S. GRIGORYAN
et al.
PRC72 034906(2005)
Hep-ph/0507084(2005)
Good sensitivity J/Y, ?(1S) ?(2S)
Quarkonia
18
Electroweak Boson Detection
Z. CONESA, L. APHECETCHE, Ch. FINCK and G.
MARTINEZ
PbPb MB 14400 muons from W

• Well known from SM (better than 10)
• In principle no-interaction with QGP
• Non explored region
• (M, x) (80-90 GeV/c2, 10-3 - 10-4)
• Luminosity and detector efficiency cross-check
• Reference of quark (b) energy loss

Di-muons from Z0 240 Z0 ? mm in MB PbPb 2400 Z0
? mm in MB ArAr
ElectroWeak
19
Conclusions

• Heavy Flavour production will be measured by
  ALICE in AA collisions at LHC energies
• Exclusive open charm (D0, D) combined to
  single-lepton and di-lepton continuum
  measurements of beauty
• Huge statistics on charmonia v2, polarization
• Regeneration Centrality and pT dependance
• Bottomonia measurement ?(2S)/?(1S)
• Electro-weak boson can be measured in AA
  reference for beauty energy loss
• Ds, Lc, J/y from B, multi-muon events, etc. have
  not been addressed in this talk but should be
  accessible with ALICE.

Conclusions
20
Acknowledgements
Special thanks to R. Arnaldi, F. Antinori, L.
Aphecetche, N. Bastid, Ch. Blume, E. Bruna, Z.
Conesa del Valle, Ph. Crochet, A. Dainese, Ch.
Finck, S. Grigoryan, F. Guerin, M. Lunardon, F.
Prino, K. Safarik, E. Scomparin, R. Turrisi, J.
Schukraft, W. Sommer, D. Stocco and E.
Vercellin for fruitful discussions and the
preparation of this talk.
Caminante, son tus huellas el camino, y nada
mas caminante no hay camino, se hace el camino
al andar Antonio Machado (H. S. QM2002, Nantes)
ALICE will begin to walk next year!