Charm at RHIC

Recent results on
Charm Production
in
Heavy Ion Collisions
Gunther Roland
Mumbai
Dec 8 2005
Data
• Summary of data from QM 2005
• Data/plots from experiment overview talks:
– PHENIX: Henner Buesching, Vicki Green,
Sergey Butsyk
– STAR: Jamie Dunlop, Frank Laue
– NA60: Enrico Scomparin, Roberta Arnaldi
– NA50: Luciano Ramello
J/psi suppression at CERN
• NA50: Re-analysis of 158 AGeV Pb+Pb data
• NA60: First results of 158 AGeV In+In
NA50 J/psi over DY vs centrality
NA50 results
psi’ over DY vs L
NA50 pT dependence
NA60 Di-muon Spectrum
J/y
Charm
y’
Background
DY
NA60 In-In Results
Centrality Dependence
L does not appear to be a
good scaling variable
Comparison to models
Models were tuned to NA50 Pb+Pb data
Satz, Digal, Fortunato
Rapp, Grandchamp, Brown
Capella, Ferreiro
Charm at RHIC
1. PHENIX, STAR: Charm cross-section in
d+Au, Au+Au
2. PHENIX: J/psi suppression - new results
from 200 GeV Au+Au, first results from
200 GeV Cu+Cu
3. PHENIX, STAR: Flow of ‘charm’ hadrons
Charm production at RHIC
0-80% Au+Au
STAR Preliminary
Signal seen in STAR for J/ψ in Au+Au
Open “Charm” at RHIC
• “Charm” yields and “charm” flow
– NOT based on identified charm hadrons
– Based on ‘non-photonic’ electrons from semileptonic decays
• Subtract electron production from gamma
conversions
• Different methods in STAR (inv mass cuts), PHENIX
(converter runs)
– Significant contribution from B quarks?
Non-photonic electrons
RAA for non-photonic electrons
Suppression of charm at high pT?
(1) q_hat = 0 GeV2/fm
(4) dN g / dy =
1000
(2) q_hat = 4 GeV2/fm
(3) q_hat = 14
GeV2/fm
Expectations for heavy flavor
suppression
Bottom contribution was supposed to be unsuppressed!?
Charm at RHIC
1. PHENIX, STAR: Charm cross-section in
d+Au, Au+Au
2. PHENIX: J/psi suppression - new
results from 200 GeV Au+Au, first
results from 200 GeV Cu+Cu
3. PHENIX, STAR: Flow of ‘charm’ hadrons
Published PHENIX result
200 GeV Au+Au
RUN 2002
RUN 2004
PHENIX pp and dAu results
New PHENIX Results
J/y mm
muon arm
1.2 < |y| < 2.2
J/y ee
Central arm
-0.35 < y < 0.35
dAu
AuAu
CuCu
AuAu
CuCu
mm
mm
mm
ee
ee
200 GeV/c 200 GeV/c 200 GeV/c 200 GeV/c 200 GeV/c
CuCu
mm
62 GeV/c
Model comparison, I
Muon arm
Theory Vogt:
nucl-th/0507027
Central arm
Model comparison, II
Model comparison, III
SPS vs RHIC comparison
pT Broadening?
without recombination
only pT broadening
with recombination
+ pT broadening
J/psi rapidity distribution
Recombination (Thews et al) predicts narrowing
No quantitative comparison yet (need better pp data)
pT dependence of suppression
Quarkonia in CMS
Resolution ~ 40MeV
Charm at RHIC
1. PHENIX, STAR: Charm cross-section in d+Au,
Au+Au
2. PHENIX: J/psi suppression - new results from
200 GeV Au+Au, first results from 200 GeV
Cu+Cu
3. PHENIX, STAR: Flow of ‘charm’ hadrons
Flow for heavy hadrons
(made of light quarks)
Charm flow in Au+Au (STAR)
STAR vs PHENIX vs Theory
Theory:
Greco, Ko, Rapp: PLB 595 (2004) 202