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30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 1
Overview of heavy flavor v2
ShinIchi Esumi, Inst. of Physics Univ. of Tsukuba
(1) RAA and v2 of various particle species meson/baryon and hadron/photon hydro-collective flow and recombination (2) Heavy flavor electron measurements non-photonic electron RAA, pT slope, v2
charm quark collectivity (radial/elliptic)(3) Future single muon v2, D v2, J/ v2
STAR/PHENIX upgrade
I. Choi, W. Dong, M. Issah, R. Lacey, H. Masui, S. Sakai, N. Xu, Z. Xu, Y. Zhang
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 2
Nuclear modification factor : RAA, RCP
direct photon
hadrons
baryons
mesons
(1) suppression of hadrons in Au+Au collisions at RHIC with respect to binary N-N collision scaling(2) baryon vs meson difference(3) no suppression in direct photon
RAA=yieldAA/(yieldpp*Ncoll_AA)RCP=(yieldcent/Ncoll_cent)/(yieldperi/Ncoll_peri)
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 3
0.0
0.1
0.2
v2
Elliptic event anisotropy : v2
R * v2(dire. )R = N
incl. / Nhadronic
baryons
mesons
(3) The measurement (smaller v2) favors prompt photon production for dominant source of direct photon.
(1) hydro-like mass ordering(2) baryon/meson ordering in hadron v2
Phys. Rev. Lett. 96, 032302 (2006)
N
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 4
quar
k nu
mbe
r sc
aled
v2
orig
inal
had
ron
v 2
KET = mT – mass (hadron)
mT + nquark scaling of v2
nquark scaling alone
mT scaling alone
mT + nquark scaling
WWND 2006, M. Issah
mass
mT s
lop
e
A+A
p+p
radial flow
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 5
Hydro-trend at low pT & quark recombination at mid pT
This mT + nquark scaling includes both hydro-trend and quark recombination, therefore it’s not really new. It gives a good description of large sets of data for wider pT region (low-pT to mid-pT), but fails at higher pT.
v2
pT (GeV/c) S
STAR preliminary0-80% Au+Au 200GeVYan Lu SQM05P. Sorensen SQM05M. Oldenburg QM05
PHENIX preliminary0-93% Au+Au 200GeVH. Masui QM05
mT + nquark scaling
mT + nquark scaling
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 6
Quark recombination needed also for J/ data…
no recombination
no recombination
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 7
Early freeze-out for and J/, but still flows
Compiled by N. Xu, SQM 2006PHENIX (, K, p, J/): PRC69, 034909(04), QM05; STAR (, , ): QM05
SPS SPS
RHIC
a hint for non-zero radial flow of J/ in early hadronic stage or flow of charm quark in late QGP phase
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 8
Semi-leptonic decay of open-charm
Ne : inclusive electron yield
material amounts : 0
1.1% 1.7%
Dalitz : 0.8% X0 equivalent
0
With converterConversion in converter
W/O converter
0.8%
Non-photonic
Conversion from known material
? %
Photonic
cocktail method
converter method
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 9
Non-suppressed total charm yield (lower pT)
Non-suppressed charm yield at low pT : they are initially produced and survived until the end, did they interact with the produced hot matter?
We do not know the answer, that’s why we also measure their v2 and pT slope.
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 10
Radial flow of charm quark Yifei Zhang
AuAu Central charm hadron
AuAu Central , K, p
AuAu Central strangeness
hadron
another hint for non-zero radial flow of D-meson or flow of charm quark!?
Brast-wave fit to D-meson and single electron and muon from D-meson decay spectra
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 11
Run04: X=0.4%
Run02: X=1.3%
Non-pho./pho.
inclusive e v2
photonic e v2
line : estimated with 0 v2
measurement and simulation
e v2 without converter
Inclusive electron v2 and photonic contribution
Estimation of photonic electron v2 :decay kinematics simulation and/or experimental determination via with/without converter measurement.
Ratio of non-photonic over photonic electron yields (which is S/N) should be given in order to extract non-photonic electron v2.
e v2 with converter to enhance photonic electron yield
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 12
Extracted non-photonic electron v2
coalescence model prediction.with/without charm quark flowGreco, Ko, Rapp: PLB 595 (2004) 202
v2incl. =
Nnon-ph. v2non-ph. + Nphot. v2
phot.
Nnon-ph. + Nphot.
the 3rd hint for non-zero elliptic flow of charm quark!?
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 13
PHENIX preliminary data
(1) different v2(pt) shape assumptions for D meson (2) pT distribution by pythia tuned to reproduce electron spectra at 130GeV Au+Au(3) 2 restricted up to pT<2GeV/c
2 test with one free amplitude parameter : v2 = A * f(pT)
Extraction of D meson v2 Shingo Sakai
Minimum data are plottedfor each assumption
electron v2 fromD meson decay
D meson v2
D meson v2
D meson v2 : between and d
massD meson ~ massdeuteron
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 14
u/d/(s) quarks v2
mass effect in number of quark scaling
v2meson (pT) = v21 (R1 pT) + v22 (R2 pT) Ri = mi / mM
(mi : effective mass of quark i)
(Phys.Rev. C68 (2003) 044901 Zi-wei & Dence Molnar)
v2π(pT) ~ 2*v2q(1/2pT) v2D(pT) ~ v2u (1/6*pT) + v2c (5/6*pT)
c quark v2
0 0
Extraction of charm quark v2 Shingo Sakai
quark pT (GeV/c)
qua
rk v
2
Different shape assumptions for D meson v2 are propagated from the previous page in order to extract charm quark v2, the same minimum data are chosen again for each assumption.
Shingo preliminary
B. Zhang et al., nucl-th/0502056
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 15
v2D = v2
B : flat or decreasing
D e
B e (v2
B : flat at high pT)
B e (v2B : decreasing at high pT)
pT (GeV/c)
v 2
pT
Electron v2 from B meson Shingo Sakai
If B meson decay dominates non-photonic electron yield (RBD ~ 1) already at 2~3GeV/c (unlikely?), v2
B could be as large as v2D.
Otherwise, v2B should be smaller.
RBD measurement will be crucial.
1
0
Nelec.D + Nelec.
B
Nelec.B
to be determinedExperimentally
RBD =
RBD
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 16
Electron v2 analysis in STAR Weijiang Dong
dE/dx in TPC
Shower shape in EMC
Momentum in TPC vs. Energy in EMC
Conversion and dalitz rejection with minv.
The detector material in STAR caused too much photonic background, which caused huge systematic and statistical uncertainties. Our result is not sensitive enough to make any conclusion about heavy quark v2 so far. More work ahead! --- Weijiang, 8/Dec/2005
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 17
J/ v2, D v2, single muon v2
prompt muon ~ few %
pun.-thr. had ~ few %
decay muon> 90%
z-vertex position
nu
mb
er o
f fu
ll t
rack
trackeridentifier absorber
collision vertex rangeprompt muon
decay muon
punch-through hadron
stopped hadron
99% hadron absorbed
We only need high statistics for D, J/ v2.
Hadron measurement in muon arm is “easy”. We look for a few % prompt muon signal out of fully reconstructed tracks
~ 800(ee) + ~ 5000() J/s from full run4 200GeV Au+Au
Ihnjea Choi
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 18
R=50mm
R=180mm
R=330mm
R=50mm
R=180mm
R=330mm
A new reaction plane detector (1~||~2.5, cos2~ 0.7, Pb converter + scintillator) in PHENIX this summer 2006
Future upgrade of STAR/PHENIX detectors
Heavy Flavor Tracker for STAR
Vertex Vertex Tracker, Tracker, Forward Forward
Calorimeter Calorimeter for PHENIXfor PHENIX
PHENIXPHENIXmuon armmuon arm
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 19
Thank you very much!
(1) RAA and v2 of various particle species meson/baryon and hadron/photon hydro-collective flow and recombination (2) Heavy flavor electron measurements non-photonic electron RAA, pT slope, v2
charm quark collectivity (radial/elliptic)(3) Future single muon v2, D v2, J/ v2
STAR/PHENIX upgrade
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 20
inclusive and 0 v2
nucl-ex/0508019
v2 of direct photon gives complimentary information in understanding the origin of binary scaled direct photon production.
Bresmsrahlung, because of largerenergy loss v2 < 0
fragmentation
in vacuum, from escapedpartonv2 > 0
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 21
try to extract direct v2
v2direct =
R v2inclusive – v2
b.g.
R – 1
v2b.g. : expected v2 from hadronic decays
if v2direct = 0 R =
v2inclusive
v2b.g
nucl-ex/0508019
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 22
QM05 : Phenix preliminary run4inclusive and 0 v2
0
inclusive
v2
0 5 pT (GeV/c) 10
0-10 % 10-20 %
30-40 %
50-60 %40-50 %
20-30 %
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 23
(3) q_hat = 14 GeV2/fm
(2) q_hat = 4 GeV2/fm
(1) q_hat = 0 GeV2/fm
(4) dNg / dy = 1000
non-photonic electron v2 is similar with other hadronsnon-photonic electron v2 is similar with other hadronsat low pat low pTT but smaller at higher p but smaller at higher pTT region 4~5GeV/c region 4~5GeV/c
photonic electron v2 originated from photonic electron v2 originated from 00
is above is above 00 v2 at low pT and similar to v2 at low pT and similar to 00 v2 at high pT and v2 at high pT and subtracted already.subtracted already.
Non-photonic electron is less suppressed compared with 0, but it is still a significant suppression RAA~ 0.3 at higher pT region 4~5GeV/c
Non-photonic electron (charm origin) RAA compared with 0 RAA
Important note : RAA is much closer to unity at lower pT compared with 0 or other hadrons
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 24
B. Zhang et al.nucl-th/0502056
significant suppression at higher pT, almost same as 0 suppression above 5GeV/c
b contributionless suppressionless interaction
b contributionless flowless thermalized
Non-photonic electron : charm (+beauty) RAA and v2
some difference between experiments at higher pT, which needs to be solved. D-meson flows (+ve v2), should determine charm v2
30/Mar/2006, SQM, UCLA ShinIchi Esumi, Univ. of Tsukuba 25
rather good description above 1GeV/c in quark pT
remaining mass dependence at lower pT region
QM05 PHENIX QM05 STAR
Number of quark scaling of v2
v2 is already formed during quark phase before hadronizationadditional hadronic flow might be there after hadronization