Zebo Tang University of Science and Technology of China (USTC)
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Transcript of Zebo Tang University of Science and Technology of China (USTC)
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 1Zebo Tang, USTC
Zebo TangUniversity of Science and Technology of China (USTC)
Open and Closed Charm measurements at RHIC
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 2Zebo Tang, USTC
Open charm measurements at RHIC
STAR measurements:
Signal/Spectra
D0 K c + X (y=0, low pT) c e + X
Flow & energy loss
Radial flow from NPE
RAA from NPE
Correlations
D*-jet, e-h, e-D0
PHENIX measurements:
Signal/Spectra
D0 K-+0 c + X (<y>=1.65, pT>1 GeV/c) c e + X e+e-
Flow & energy loss
Elliptic flow from NPE
RAA from NPE
Correlations
e-h, e-
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 3Zebo Tang, USTC
Energy lossPHENIX: PRL98(2007)172301STAR: PRL98(2007) 192301
Strong suppress, energy lossSimilar magnitude as light hadronsBottom yields and bottom energy loss?
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 4Zebo Tang, USTC
Heavy flavor feeddown
Good high pT J/ measurements are neededSmall effect on RAA
No conclusion change
Carla M. Vale, QM2009
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 5Zebo Tang, USTC
Correlation
arXiv:0903.4851
B is also suppressedRadiative energy loss unfavored
Bertrend Biritz, QM2009
PHENIX, arXiv:0903.4851
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 6Zebo Tang, USTC
Jet flavor conversion?
pT (GeV/c)
STAR preliminary
hardparton
path length L
Quark
Quark
path length L
Quark
gluon
hardparton
Kaon consistent with Jet conversionHow about charm and bottom?How about LHC energy?
Yichun Xu, QM2009
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 7Zebo Tang, USTC
Forward rapidityCarla M. Vale, QM2009
More suppression at forward rapidity? need more statistics, better systematic control, and in Au+Au
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 8Zebo Tang, USTC
Quarkonium melting in medium
?
• Suppression has long be proposed as a signature of QGP formation
• Plasma thermometer
• Quarkonium production mechanism
Ágnes Mócsy, QM2009
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 9Zebo Tang, USTC
Charmonium production mechanism
NRQCD
Color singlet
Color octet
Color singlet model (CSM), LO
underpredicted CDF data by order of magnitude
Color octet model (COM), LO
good agreement with CDF cross section
disagreement with CDF polarization
CSM*, NLO
better agreement
NNLO* applicable at pT>5-7 GeV/c
COM*
improvement of polarization,
NLO will come, valid at pT>3 GeV/c
CSM+s-channel cut
valid at low pT
Decay feeddown (CDF):
(2s): 7%-15%, slightly increase with pT
c0,1,2: ~30%, slightly decrease with pT
B: Strong pT dependence
LO
Know your reference!
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 10Zebo Tang, USTC
Charmonium measurements at RHIC
STAR measurements:
Mid-rapidity (ee)
L2 J/ trigger:
low pT in p+p
EMC trigger:
high pT in p+p, Cu+Cu, d+Au
BJ/ in p+p
Minbias:
low pT in Au+Au, Cu+Cu, d+Au
Forward rapidity (ee)
J/ and c in p+p (2.5<<4.0)
PHENIX measurements:
Mid-rapidity (ee)
J/ in p+p, d+Au, Cu+Cu, Au+Au (low and intermediate pT)
’ and c in p+p
Forward rapidity ()
J/ in p+p, d+Au, Cu+Cu, Au+Au
(1.2<||<2.2)
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 11Zebo Tang, USTC
Low pT spectra in p+p
CSM+s-channel cut works well at intermediate pT
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 12Zebo Tang, USTC
High pT spectra in p+p
Significantly extend previous measurements from 5 to 14 GeV/c
CEM, LO COM describe overall trend, leave little to no room for feeddown
NNLO* CSM, steeper than data
STAR Preliminary
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 13Zebo Tang, USTC
xT scaling
n is related to thenumber of point-likeconstituents takingan active role in theinteraction
n=8: diquark scattering
n=4: QED-like scattering
and proton at pT>2 GeV/c: n=6.6±0.1 (PLB 637, 161(2006))
J/ at high pT: n=5.6±0.2 (close to CS+CO prediction)
Soft processes affect low pT J/ production
pT>2 GeV/c
STAR Preliminary
pT>5 GeV/c
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 14Zebo Tang, USTC
Forward rapidity
J/ cJ/Further constrain models
High xF intrinsic heavy flavor
Chris Perkins, QM2009
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 15Zebo Tang, USTC
PolarizationCesar Luiz da Silva, QM2009
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 16Zebo Tang, USTC
Feeddown
R(ψ’) =8.6±2.5% PHENIXR(c) <42% (90%C.L.) PHENIX
Susumu X. Oda, QM2008
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 17Zebo Tang, USTC
BJ/
No significant near side correlationB contribution (13 5) %Little room for parton fragmentation
STAR PreliminaryarXiv:0904.0439
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 18Zebo Tang, USTC
Constrain bottom yields
• pQCD predicts significant BJ/ • correlations shows low B contribution• can be used to further constrain B yields• constrain Be
M. Cacciari, P. Nason and R. Vogt RL 95(2005),122001; CLEO collaboration PRL 89(2002),282001
STAR PreliminaryarXiv:0904.0439
Gang Wang, QM2008
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 19Zebo Tang, USTC
RAA at low pT
PHENIX, PRL98, 232301
• Similar suppression as that at SPS• More suppression at forward rapidity• Regeneration? Sequential suppression?
J/
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 20Zebo Tang, USTC
RAA at high pT
STAR Cu+Cu 0-20%:RAA(pT>5) = 1.40.40.2No suppression
RAA(pT~5.5)>0.6 (86% C.L.)RAA(pT~7.0)>0.6 (82% C.L.)Combined: 97%Indicates increase of RAA
RAA(pT~5.5)>AdS/CFT+Hydro (93% C.L.)RAA(pT~7.0)>AdS/CFT+Hydro (94% C.L.)Combined: 99%Contrast to AdS/CFT+Hydro prediction
PHENIX Spectra not available, prevents statistics analysisNo way PHENIX can make conclusion contrasting to STAR
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 21Zebo Tang, USTC
RAA at high pT
• Consistent with no suppression at high pT: RAA(pT>5 GeV/c) = 1.4± 0.4±0.2
• Indicates RAA increase from low pT to high pT
• How does production mechanism (CS vs. CO) affect energy loss?• Contrast to AdS/CFT+ Hydro prediction (H. Liu, K. Rajagopal and U.A. Wiedemann PRL 98, 182301(2007), T. Gunji, JPG 35, 104137(2008)
• Good jobs: • two-component model, leakage and B feeddown is important (R. Rapp, X. Zhao, arXiv:0806.1239)
• transport+hydro, from initial produced instead of regenerated (Y.Liu, Zhen Qu, N. Xu and P. Zhuang, arXiv:0901.2757)
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 22Zebo Tang, USTC
Elliptic flow
Inherit open charm flow or not? Regeneration?Too early to compare to models, need more statistics
pT integrated v2 = (-10±10)% @ |y|<0.35 and (-9.3 ± 9.2)% @ -1.2<|y|<1.2 Ermias T. Atomssa
QM2009
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 23Zebo Tang, USTC
Future
PHENIXJ/500 GeV p+p
STARJ/eeL3 trigger, Online tracking
More and more statisticsBetter and better detectorsBetter and better techniques
Bright future, better understanding
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 24Zebo Tang, USTC
backup
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 25Zebo Tang, USTC
Why heavy flavorWicks et al, NPA 784 (2007) 426Muller nucl-th/0404015
• Heavy quark masses are not modified by QCD vacuum. Strong interactions do not affect them.
• Important tool for studying properties of the hot-dense matter created at RHIC energy.
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 26Zebo Tang, USTC
Flow
1. Tfo = 220 MeV (best fit) – freeze out earlier <t> = 0.23 (best fit), <0.42 (1-) favor moderate or small radial flow.
2. Sizable v2 strong-interacting Quark Gluon Plasma
STAR Preliminary
PRL, 98, 172301 (2007), D. Hornback, QM2008STAR: nucl-ex/0805.0364, Y. Zhang, QM2008
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 27Zebo Tang, USTC
STAR Preliminary
Beam pipe + SVT + SSD+ Dalitz
Beam pipe + Dalitz
TPC Inner Field cage
Cou
nt
Outlook: HF-lepton
Projection (0.4/nb)Run-8
Run-3
Run 8 data compared to run3
Material in front of TPC reduced by an order of magnitude
Final charm cross section is in progress
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 28Zebo Tang, USTC
Outlook: Direct reconstruction
D0
Phys. Rev. Lett. 94 (2005)
S. Butyk (QM2008 poster)PHENIX Preliminary
Year5 pp 200 GeV
Before background
HFTSimulation
Small signal to background ratio
Precise vertexing will helps a lot
Still long way to go
RHIC&AGS Users' Meeting, BNL, June 1-5, 2009 29Zebo Tang, USTC
How does open affect closed
Open charm Radial flow (thermal)
Sizeable elliptic flow
Strong suppression at high pT (energy loss)
Total charm cross section
Be
Charmonium Regeneration possible
Inherit elliptic flow
Lose energy (CO)
No energy loss (CS)
Model input
BJ/