Transcript Document

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/y 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
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Nuclear modification factor : RAA, RCP
(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
)
baryons
direct photon
mesons
hadrons
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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f
Elliptic event anisotropy : v2
baryons
v2
N
DF
Phys. Rev. Lett. 96, 032302
(2006)
0.2
0.1
mesons
0.0
(1) hydro-like mass ordering
(2) baryon/meson ordering
in hadron v2
R * v2(dire. g )
R = Ngincl. / Nghadronic
(3) The measurement (smaller v2) favors prompt photon
production for dominant source of direct photon.
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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mT + nquark scaling of v2
quark number scaled v2
original hadron v2
WWND 2006, M. Issah
30/Mar/2006, SQM, UCLA
mT slope
radial flow
mT scaling alone
p+p
mass
KET = mT – mass (hadron)
nquark scaling alone
mT + nquark scaling
ShinIchi Esumi, Univ. of Tsukuba
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Hydro-trend at low pT & quark recombination at mid pT
v2
PHENIX preliminary
0-93% Au+Au 200GeV
H. Masui QM05
mT + nquark scaling
pT (GeV/c)
K0 S L
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.
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
X
W
STAR preliminary
0-80% Au+Au 200GeV
Yan Lu SQM05
P. Sorensen SQM05
M. Oldenburg QM05
mT + nquark scaling
5
Quark recombination needed also for J/Y data…
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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Early freeze-out for f, X, W and J/y, but still flows
Compiled by N. Xu, SQM 2006
PHENIX (, K, p, J/y): PRC69, 034909(04), QM05; STAR (f, X, W): QM05
SPS
SPS
a hint for non-zero radial flow of
J/y in early hadronic stage or flow
of charm quark in late QGP phase
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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Semi-leptonic decay of open-charm
Ne
: inclusive electron yield
1.7%
0.8% 1.1% ? %
With converter
Conversion in converter
Photonic
W/O converter
Conversion from known material
cocktail method
Dalitz : 0.8% X0 equivalent
converter method
Non-photonic
0
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
material amounts :
0
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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
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Radial flow of charm quark
AuAu Central
charm hadron
Yifei Zhang
AuAu Central
strangeness
hadron
another hint for
non-zero radial
flow of D-meson
or flow of charm
quark!?
AuAu Central
, K, p
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
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Inclusive electron v2 and photonic contribution
Estimation of photonic electron v2 :
decay kinematics simulation and/or
experimental determination via
with/without converter measurement.
e v2 with converter to enhance
photonic electron yield
Ratio of non-photonic over photonic
electron yields (which is S/N) should
be given in order to extract nonphotonic electron v2.
e v2 without converter
photonic e v2
line : estimated with 0 v2
measurement and simulation
Non-pho./pho.
Run04: X=0.4%
inclusive e v2
Run02: X=1.3%
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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Extracted non-photonic electron v2
coalescence model prediction.
with/without charm quark flow
Greco, Ko, Rapp: PLB 595 (2004) 202
v2incl. =
Nnon-ph. v2non-ph. + Nphot. v2phot.
Nnon-ph. + Nphot.
the 3rd hint for non-zero
elliptic flow of charm
quark!?
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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Extraction of D meson v2
D meson v2
c2 test with one
free amplitude
parameter :
v2 = A * f(pT)
Minimum c2 data are plotted
for each assumption
Shingo Sakai
electron v2 from
D meson decay
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) c2 restricted up to pT<2GeV/c
D meson v2
D meson v2 : between  and d
massD meson ~ massdeuteron
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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Extraction of charm quark v2
Shingo Sakai
B. Zhang et al.,
nucl-th/0502056
mass effect in number of quark scaling
(Phys.Rev. C68 (2003) 044901
Zi-wei & Dence Molnar)
0
0
Shingo preliminary
quark v2
v2meson (pT) = v21 (R1 pT) + v22 (R2 pT)
Ri = mi / mM
(mi : effective mass of quark i)
u/d/(s) quarks v2
v2π(pT) ~ 2*v2q(1/2pT)
v2D(pT) ~ v2u (1/6*pT) + v2c (5/6*pT)
Different shape assumptions for D meson v2
are propagated from the previous page in
order to extract charm quark v2, the same
minimum c2 data are chosen again for each
assumption.
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
c quark v2
quark pT (GeV/c)
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Electron v2 from B meson
Shingo Sakai
v2
If B meson decay dominates non-photonic electron
yield (RBD ~ 1) already at 2~3GeV/c (unlikely?),
v2B could be as large as v2D.
Otherwise, v2B should be smaller.
RBD measurement will be crucial.
Nelec.B
RBD =
Nelec.D + Nelec.B
v2D = v2B : flat or decreasing
1
D -> e
RBD
B -> e
(v2B : flat at high pT)
0
pT
B -> e (v2B : decreasing at high pT)
pT (GeV/c)
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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Electron v2 analysis in STAR
dE/dx in
TPC
Weijiang Dong
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
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J/y v2, D v2, single muon v2
identifier
tracker
decay muon
absorber
Ihnjea Choi
99% hadron
absorbed
stopped hadron
punch-through
hadron
prompt muon
~ 800(ee) +
~ 5000(mm) J/ys
from full run4
200GeV Au+Au
30/Mar/2006, SQM, UCLA
Hadron measurement in
muon arm is “easy”.
We look for a few %
prompt muon signal out
of fully reconstructed
tracks
ShinIchi Esumi, Univ. of Tsukuba
number of full track
We only need high
statistics for D, J/Y v2.
collision vertex
range
> 90%
decay muon
pun.-thr. had ~ few %
prompt muon ~ few %
z-vertex position
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Future upgrade of STAR/PHENIX detectors
A new reaction plane detector
(1~|h|~2.5, <cos2DF> ~ 0.7,
Pb converter + scintillator)
in PHENIX this summer 2006
R=330mm
Heavy Flavor Tracker for STAR
R=180mm
R=50mm
PHENIX
muon arm
30/Mar/2006, SQM, UCLA
Vertex
Tracker,
Forward
Calorimeter
for PHENIX
ShinIchi Esumi, Univ. of Tsukuba
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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/y v2
STAR/PHENIX upgrade
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
19
inclusive g and 0 v2
v2 of direct photon gives complimentary information in
understanding the origin of binary scaled direct photon production.
Bresmsrahlung,
because of larger
energy loss
v2 < 0
fragmentation
in vacuum,
from escaped
parton
v2 > 0
nucl-ex/0508019
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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try to extract direct g v2
direct g
v2
=
R v2inclusive g – v2b.g.
if
R–1
v2direct g
=0
R=
v2b.g
v2inclusive g
v2b.g. : expected g v2 from hadronic decays
nucl-ex/0508019
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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inclusive g and 0 v2
v2
0-10 %
QM05 : Phenix preliminary run4
10-20 %
0
inclusive g
20-30 %
30-40 %
40-50 %
50-60 %
0
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
5
pT (GeV/c)
10
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Non-photonic electron (charm origin) RAA compared with 0 RAA
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 v2 is similar with other hadrons
at low pT but smaller at higher pT region 4~5GeV/c
(1) q_hat = 0 GeV2/fm
(4) dNg / dy = 1000
photonic electron v2 originated from 0
is above 0 v2 at low pT and similar to
0 v2 at high pT and
subtracted already.
(2) q_hat = 4 GeV2/fm
(3) q_hat = 14 GeV2/fm
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
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Non-photonic electron : charm (+beauty) RAA and v2
significant suppression at higher pT, almost
same as 0 suppression above 5GeV/c
some difference between experiments at higher pT,
which needs to be solved.
D-meson flows (+ve v2), should determine charm v2
b contribution
less suppression
less interaction
b contribution
less flow
less thermalized
B. Zhang et al.
nucl-th/0502056
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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Number of quark scaling of v2
rather good description above 1GeV/c in quark pT
remaining mass dependence at lower pT region
QM05 PHENIX
QM05 STAR
v2 is already formed during quark phase
before hadronization
additional hadronic flow might be there
after hadronization
30/Mar/2006, SQM, UCLA
ShinIchi Esumi, Univ. of Tsukuba
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