Collectivity makes the world go around
Kai Schweda
Physikalisches Institut
University of Heidelberg / GSI Darmstadt
Hans Georg Ritter Symposium
3/15/13
RNC group in 2001
Ian Johnson Fabrice Retiere Art Poskanzer Nu Xu student from South Africa
David Hardtke Peter Jacobs Jay Marx
Howard Wieman Jim Thomas
Jennifer Klay Jinghua Fu
Eugene Yamamoto
3/15/13
Howard Matis
Masashi Kaneta
Kirill Filimonov
Falk Meissner
me
Hans Georg
1/5
Grazyna Odyniec
on top of the world
Hans Georg
high-energy nucleus-nucleus
collisions
central collision
collision
happens here
size ~10fm
4000 charged
particles
illuminates
TPC volume
size ~4m
STAR year 2 data
White papers - STAR: Nucl. Phys. A757, p102.
3/15/13
Hans Georg Ritter Symposium
5/24
More central collisions
Collectivity observed in spectra
strongly curved
 strong flow
exponential
 no flow
STAR: Phys. Rev. C70, 041901(R).
3/15/13
Hans Georg Ritter Symposium
6/24
matter flows - collectivity
Nu Xu plot 2.0
strange matter
flows
bulk matter
flows
STAR Data: Nucl. Phys. A757, (2005) 102.
partonic collectivity ?
3/15/13
Hans Georg Ritter Symposium
7/24
Anisotropy Parameter v2
coordinate-space-anisotropy

momentum-space-anisotropy
y
x
Initial/final conditions, EoS, degrees of freedom
discovery of partonic collectivity
elliptic flow of (multi-) strange
f and W
and
quark number scaling:
first observed in L and K0S
PhD theses of Jinghua Fu,
Wuhan/LBNL and Paul
Sorensen, UCLA/LBNL
 partonic collectivity
S. Voloshin, QM02, 379c (2003)
STAR, PRL 95, 122301 (2005)
PHENIX, PRL 98, 162301 (2007)
STAR, PRC 75, 054906 (2007)
STAR, PRL 95, 122301 (2005)
9/24
higher harmonics
• extract power spectrum of vn,
like WMAP*
• higher harmonics
• odd harmonics important
• v3: access h/s
STAR, arXiv:1301.2187 [nucl-ex];
STAR, PRL 92 (2004) 062301;
A. Mocsy and P. Sorensen, NPA 855 (2011) 241;
B. Alver and G. Roland, PRC 81 (2010) 054904;
*WMAP data: The NASA/WMAP Science team;
http://map.gsfc.nasa.gov/media/080997/index.html.
QGP plot: B. Schenke, S. Jeon, and C. Gale, arXiV:1109.6289.
3/15/13
Hans Georg Ritter Symposium
10/24
everything counts in large amounts
M. Sumbera, arXiv:1301.7224 [nucl-ex].
3/15/13
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11/24
entering the anti-world
STAR, Nature 473 (2011) 353.
• anti-alpha discovered
• rarest signal in HI ever observed (2/108)
3/15/13
Hans Georg Ritter Symposium
12/24
STAR: key to success
large acceptance
Hans Georg
low-pT
coverage
excellent PID
large data
sets
3/15/13
Hans Georg Ritter Symposium
13/24
Go heavy or go home !
• new scale:
mc,b » LQCD
•
mc,b ≈ const.
• mu,d,s ≠ const.
X. Zhu, M. Bleicher, S.L. Huang, K.S., H. Stöcker,
N. Xu, and P. Zhuang, PLB 647 (2007) 366.
3/15/13
Hans Georg Ritter Symposium
14/24
Where does all the charm go ?
J/(charmonium)
Ds
D±
Lc
D*+
D0
• Total charm cross section: open-charmed hadrons,
e.g. D0, D+, D*+, Lc, … and c,b  e() + X
• Quarkonia, e.g. J/ carries 1% of total charm
3/15/13
Hans Georg Ritter Symposium
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Open-charm production
•
at RHIC: large
combinatorial background
•
PhD thesis
Xin Dong USTC/LBNL
•
STAR upgrade with Heavy
Flavor Tracker will impose
high precision
STAR, PRD 85 (2012) 092010;
ALICE, JHEP 1207 (212) 191.
3/15/13
Hans Georg Ritter Symposium
16/24
Heavy-quark detection
• golden channel: D0  K- +  ,
c = 123 m
• displaced decay vertex is
signature of heavy-quark
decay
plot: courtesy of D. Tlusty.
3/15/13
Hans Georg Ritter Symposium
17/24
Heavy Flavor Tracker
HFT
SSD
IST
PXL
3/15/13
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18/5
The Heavy Flavor Tracker for STAR
• Hans Georg with an
HFT prototype
• 10 m precision
demonstrated
• 10 weeks of running
in 2014 will decisively
address open charm
at RHIC
some more statistics
• STAR white paper:
Nucl. Phys. A757 (2005) 102
1581
- most cited RHIC paper
- most cited HI experimental paper
• Bjorken, PRD 27 (1983) 127
2023
• Mastsui and Satz, PLB 178 (1986) 416
1719
3/15/13
Hans Georg Ritter Symposium
20/24
populating the world …
Dan Cebra Javier Castillo Xin Dong
Davis
CEA
LBNL
Ian Johnson
PSI
Kirill Filimonov
Berkeley
Jinghua Fu
Wuhan
Tom Gutierrez
San Luis Obispo
Masashi Kaneta Jennifer Klay Marco v. Leuween Mike Lisa Spiros Margetis
Tohoku
San Luis Obispo Utrecht
Ohio State Kent State
Joakim Nystrand Joern Putschke Fabrice Retiere Lijuan Ruan
Bergen
Wayne State Triumf
BNL
Sevil Salur
Rutgers
Bedangadas
Mohanty
Bhubaneswar
ks
Raymond Snellings
Heidelberg Utrecht
Paul
Sorensen
BNL
Fuqiang
Wang
Purdue
some personal remarks
o ‘cultural shock’:
- flat hierarchies, informal style
- took me 6 months to get over it
o can you think about charm ?
Hans Georg in 2001
o Berkeley style:
- people doing the work are getting
exposed, i.e. plenary talks, committees, …
3/15/13
Hans Georg Ritter Symposium
Happy 69½ Birthday,
Hans Georg !
24/5