STAR Experiment at RHIC

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-

29, 2011

STAR

STAR Experiment

at RHIC


Nu Xu

for the STAR Collaboration



Nuclear Science Division

Lawrence Berkeley National Laboratory





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STAR

Outline



(1) Introduction



-

Collaboration membership status



-

Graduate students



-

Publications and physics focus



(2) Run 11 performance and recent results



(3)
Decadal Plan
and
eSTAR

Task Force




(4) Ongoing upgrades and issues

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STAR

STAR Collaboration Membership



STAR Membership:

U.S
. Labs:

Argonne,

Lawrence
Berkeley
,
Brookhaven

U.S. Universities:

UC Berkeley, UC Davis,
UCLA, Creighton,
Indiana,

UIC, Kent
State, MSU, Ohio State, Penn State, Purdue, Rice,
Texas A&M, UT Austin, Washington, Wayne State, Valparaiso, Yale,
MIT,
Kentucky
,
Old Dominion, Houston


Brazil:
Universidade

de Sao Paulo,
Universidade

Estadual

de Campinas

China
:

IOPP, USTC, Tsinghua
U,
SINAP,
IMP,
ShanDong

U

Croatia:
Zagreb
U

Czech Republic:
Institute of Nuclear
Physics,
Czech Technical U

France:
Institut

de
Recherches

Subatomiques

Strasbourg
, SUBATECH

Germany:

Frankfurt

India:
IOP, Jammu,
IIT
-
Mumbai,
Panjab

U, Rajasthan, VECC

Poland:

Warsaw
U
of
Technology, Cracow group

Russia:
MEPHI,

JINR, IHEP
,
ITEP

South Korea:
Pusan
National
U,
KISTI


1)
10 new institutes joined STAR since 2008


4 institutes left STAR since 2008 (LHC)


2) ~ 68% institutes are very active


~ 25% institutes are fairly active



3) New institutes

have applied for membership:



(1) HIT, China:

two
-
particle correlation


(2) GSI, Germany:

Hypernuclear

production


4)
New election
: May 18
th

Collaboration meeting




12 countries; 52 active institutes

~

555
scientists and
engineers

~ 396 scientific paper authors



Research topics at the QCD Lab:

-

properties of
sQGP

& QCD critical
point

-

proton spin structure

-

gluonic

matter: CGC, DPE

List of degree recipients:
153
PhD

and 21 other
degrees awarded on
STAR

research to students at
36
institutions

Jammu University
2009 Sunil
Manohar

Dogra

2009
Neeraj

Gupta

Max
-
Planck
-
Institut

2005 Frank
Simon

2004
Joern

Putschke

2002 Markus
Oldenburg

2000 Holm
Huemmler

1997 Michael
Konrad

MSU

2002 Marguerite
Tonjes

Ohio State University

2009
Zbigniew

Chajecki

2004
Selemon

Bekele

2004 M. Lopez
-
Noriega

2003 Randy
Wells

2002 Robert
Willson

Panjab

University
2010
Lokesh

Kumar
2008 Monika Sharma

Purdue
University

2010 Michel
Skoby

2008
Terry
Tarnowsky

2007 Jason
Ulery

2006
Levente

Molnar

2002 Alex
Cardenas

Rice University

2010
Jianhang

Zhou

USTC,
China

2011
Xiaofeng

Luo

2009
Yichun

Xu
2009
Zebo

Tang
2007
Haidong

Liu

2007
Yifei

Zhang

2005
Xin

Dong

2004
Shengli

Huang

2004 Lijuan
Ruan

IOP, Bhubaneswar

2010
Sadhana

Dash
2007 R.
Sahoo


2003
D.
Misra

2005 A.
Dubey


VECC

2008 P.
Netrakanti

2007 D. Das

2005 S. Das


University of Birmingham

2010
Essam

Elhalhuli

2009 Thomas Burton
2008 Anthony Timmins
2008 Leon Gaillard
2005 John Adams

2002 Matthew Lamont

UC


Los Angeles

2010 Bertrand
Biritz

2010 David
Staszak

2010 Priscilla
Kurnadi

2010 Bertrand Helmut
2010
Dhevan

Gangadharan

2008 Steve
Guertin

2006
Jingguo

Ma

2006 Johan Gonzalez

2006
Weijiang

Dong

2005 Dylan
Thein

2005 Jeff Wood

2005
Hai

Jiang

2003 Yu Chen

2003 Paul Sorensen

2002
Hui

Long

2001 Eugene Yamamoto

Univ.

Sao Paulo

2008 Mauro
Cosentino

1998 Jun Takahashi

Carnegie Mellon University

2003 Christopher Kunz

Creighton University

2006 Michael
Swanger
, MS

2003 Steve
Gronstal
, MS

2003 Nil
Warnasooriya
, MS

Texas A&M

2008 Michael
Daugherity

2006 Thomas Henry


NIKHEF/Utrecht

2011
Ermes

Braidot

2008 Federica
Benedosso

2008
Martijn

Russcher

2007
Yuting

Bai

2007
Oleksandr

Grebenyuk



MIT

2011 Matt Walker

2010 Tai Sakuma
2009 Alan Hofmann
2008 Julie
Milane


SUBATECH

2010
Artemios

Geromitsos

2005
Magali

Estienne

2004 Gael
Renault

2003
Ludovic

Gaudichet

2002 Javier
Castillo

2000
Fabrice

Retiere

2000 Walter
Pinganaud

UT
-

Austin

2009
Kohei

Kajimoto

2004
Aya

Ishihara
2004
Yiqun

Wang

2003 Bum
Choi

2002 Curtis
Lansdell

Warsaw U. of Technology

2011 Daniel
Kikola


2010
Marcin

Zawisza


2007 H.
Zbroszczyk

2004 Adam
Kisiel

University of Washington

2002 Jeff
Reid

IOPP,
Chian

2011
Jiayun

Chen
2010 Na Li
2010
Shusu

Shi
2008
Aoqi

Feng


2007
Xiaoyan

Lin

2007 Yan
Lu

2005
Zhixu

Liu

2002
Jinghua

Fu

Yale University

2011 Anders
Knospe

2010 Stephen
Baumgart

2008
Fei

Du
2009
Guoji

Lin
2009 Christine
Nattrass

2008
Oana

Catu

2007
Betty
Abelev

2006
Sevil

Salur

2005 Mark Heinz
2004
Jon
Gans

2003
Haibin

Zhang

2003 Michael
Miller

2002 Matthew
Horsley

2001 Manuel
Calderon

IUCF




2008
Weihong

He

SINAP



2010
Jian

Tian

2010 Fu Jin


2009
Xinghua

Shi
2009 Song Zhang


2008
Jin
-
Hui

Chen
2006
Guoliang

Ma

Wayne State University

2010 Sarah
LaPointe

2010 Muhammad
Elnimr

2006
Ahmed
Hamed


2005
Ying
Guo

2005 Alexander
Stolpovsky


Nucl. Physics Inst., Prague

2010 Jan
Kapitan


2010
Petr

Chaloupka

UC
-

Davis

2006 Mike
Anderson
2005
Roppon

Picha

2002 Ian
Johnson

University of Frankfurt

2006
Wetzler
,
Alexander
2006 Thorsten
Kollegger

2003
Dominik

Flierl

2003 Jens
Berger

2003 Clemens
Adler

2003
Christof

Struck



Reserches

Sub. Strasbourg

2006
Speltz
,
Jeff

2004
Julien

Faivre

2002 Boris
Hippolyte

2001 Christophe
Suire

Kent State University

2005
Camelia

Mironov

2005 Gang
Wang

2003 Ben
Norman

2002
Wensheng

Deng

2002
Aihong

Tang


LBNL

2008
Xiangming

Sun
2007 Sarah
Blyth

2007 Mark
Horner

2003 Vladimir
Morozov

LPP,
JINR, Russia
2006 Alexei
Zubanov


MEPhI
, Moscow, Russia

2007 Sergei Timoshenko


University of Zagreb

2010 Nikola
Poljak

Blue = awarded
2010
-

2011

153
Ph.D degrees

21 other degrees

(Since last review:

18)


STAR continues to do an excellent


job of educating

the next generation of physicists!

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STAR

STAR Publications

Total # of refereed publications
:

138
!


-

Phys. Rev. Lett
:

53,
Phys. Rev
:

56,
Science:

1;

Nature:

1




2010
-
2011
: Total
# of publications since last review:

14


-

Phys. Rev. Lett
:

4,
Phys. Rev
:

8,
PLB: 1; Nature: 1


and 4
manuscripts are in referee process
.


Quark Matter Conference 2011
:


4 + 2 plenary talks // 13 parallel talks // 28 posters


STAR
is well focused

and productive!

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STAR

Antimatter Discoveries by STAR at RHIC


“Observation of the
Antimatter Helium
-
4 Nucleus”



by
STAR Collaboration


Nature
, 473, 353(2011).



April
, 2011

March, 2010


“Observation of an
Antimatter
Hypernucleus




by
STAR Collaboration


Science
, 328, 58(2010).

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STAR

STAR Physics Focus

1) At 200 GeV top energy


-

Study
medium properties, EoS


-

pQCD in hot and dense medium


2) RHIC beam energy scan


-

Search for the
QCD critical point


-

Chiral symmetry restoration


Polarized
p+p

program


-

Study
proton intrinsic properties


Forward program


-

Study low
-
x properties, search for
CGC


-

Study elastic (inelastic) processes (pp2pp)


-

Investigate
gluonic exchanges

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STAR

BNL PAC, 21
-

22, 2010



HFT
2013

TPC

FGT
2011(planne
d)

STAR Detectors
Fast

and
Full

azimuthal particle identification


EMC+EEMC+FMS

(
-
1 ≤


≤ 4)

TOF

DAQ1000

MTD

2013

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STAR

(2) Run 11 performance and


recent physics results (selected)



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STAR


STAR

Efficiencies

Average of Delivered luminosity samples
is:

57% (pp 500) and 61% (AuAu200)



includes
: live time, turning on/off, problems,
pedestals, commissioning …

200 GeV Au+Au Collisions 500 GeV p+p Collisions

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STAR

A Typical Run

Level 0



Gate open







Write to RCF

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STAR

Run11: Integrated Luminosities

500 GeV p+p, transverse

FMS
~ 27pb
-
1


19.6 GeV Au+Au


MB trigger:

17M

200 GeV Au+Au


~ 2.85nb
-
1
(20B)

MB trigger:


700M







1)
500 GeV transverse p+p collisions


-

FMS, small
-
x



2)
19.6 GeV Au+Au collisions


-

critical point search


3)

200 GeV Au+Au collisions


-

di
-
electron and Upsilon


4)

Taking data at 27 GeV


1

2

3

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STAR

New TOF Performance


s
NN

= 39

GeV Au + Au Collisions

TPC

TPC+ToF

Beam Energy

Timing Resolution

Remarks

200 (GeV)

85 (
ps
)

At

39 GeV, u
sing a new calibration
scheme without information of start
time from VPD, 87
ps

of timing
resolution has been achieved.

62.4 (GeV)

90 (
ps
)

39 (GeV)

85 (
ps
)

11.5 & 7.7 (GeV)

~ 80 (
ps
)

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STAR

STAR Di
-
electron Program


1)
Direct radiation, penetrating
-
bulk probe,
new to STAR
!

2)
Beam energy, p
T
, centrality, mass dependence (
8
-
10x more events
):


R
AA
, v
2
, radial expansion, HBT, polarization, …

3) HFT/MTD upgrades: key for the correlated charm contributions.




s

= 200 GeV
p+p Au+Au
MinBias

Au+Au Central

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STAR

v
2
of J/ψ vs. p
T

1)
STAR:
TPC + TOF + HLT

2)
v
2
J/
ψ
(p
T
) ~ 0 up to p
T
= 8 GeV/c in 200 GeV Au+Au collisions

3)
Either
c
-
quarks do not flow
or
coalescence is not the dominant
process for J/ψ production at RHIC.

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STAR

ϒ(1S+2S+3S) R
AA

1)
STAR Triggered


2)
In central collisions,

(1
S+2S+3S) is
suppressed, 3
s

away
from
R
AA
= 1!


3)
R
AA

(0
-
60%)=
0.56
±
0.11(stat)+0.02
-
0.14(sys)


R
AA

(0
-
10%)=
0.34
±
0.17(stat)+0.06/
-
0.07(sys)


s
NN

= 200
GeV Au+Au collisions

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STAR

Beam Energy Scan

at
RHIC

Motivations:



Signals
of phase boundary


Signals
for critical point

Observations:




(1)
v
2

-

NCQ scaling:


partonic vs. hadronic
dof


(2) Dynamical correlations:


partonic vs. hadronic
dof


(3)

Azimuthally HBT:


1
st

order phase transition


(4) Fluctuations:


Critical points


(5) Directed flow v
1


1
st

order phase transition



-

http://drupal.star.bnl.gov/STAR/starnotes


/public/sn0493

-

arXiv:1007.2613

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STAR

LPV vs. Beam Energy

1)
Difference
between
same
-

and opposite
-
sign
correlations decreases
as beam energy
decreases

2)
Same
sign charge correlations become positive at 7.7
GeV

3)
Several different approaches in the collaboration

STAR Preliminary

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STAR

Particle and Anti
-
Particle
v
2

vs.

s
NN

1)
v
2
(

baryon) > v
2

(anti
-
baryon
); v
2
(


+
) < v
2

(

-
) at 7.7 GeV

2)
We are taking data:
27 GeV Au+Au collisions

STAR Preliminary

STAR Preliminary

STAR Preliminary

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STAR

Bedanga Mohanty

Higher Moments

of
Net
-
protons

STAR Preliminary

1)
STAR results* on net
-
proton high moments for
Au+Au collisions at

s
NN

= 200, 62.4 and 19.6
GeV.


2)
Sensitive to critical point**:



1)
Direct comparison
with Lattice results**:






4)
Extract
susceptibilities and freeze
-
out temperature.
An independent test on thermal equilibrium in HI
collisions
.

5)
17M good events at 19.6GeV collected in Run 11.


6)
We are taking data:

at 27 GeV Au+Au collisions


* STAR:
1004.4959,

PRL 105, 22303(2010).

** M.
Stephanov
: PRL,102, 032301(09).

*** R.V.
Gavai

and S. Gupta: 1001.2796.

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STAR

Quark Flavor Measurements: W
±


1)
Results* are consistent with model:
Universality of the helicity distr.
Funct
.
!

2)
Combined results of Run 9 and Run 11 reduces the error ~ 0.63.

3)
Precision measurements require
large luminosity
,
high polarization
at RHIC!













* STAR: Phys. Rev. Lett.
106
, 62002(2010).

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STAR

STAR A
LL

from 2006 to 2009

2009
STAR

A
LL

measurements
:


Results fall between predictions from DSSV and GRSV
-
STD


Precision sufficient to merit finer binning in
pseudorapidity

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STAR

Expected inclusive jet A
LL

precision


Run
12 will provide a very useful complement to Run 9


During Run 13, we can further reduce the 200 GeV
uncertainties compared to Run 9 by:


A factor of ~2 for jet p
T

>~ 12 GeV


A factor of ~sqrt(2) for jet p
T

<~ 12 GeV

Run 11

Run 12

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STAR

Recent Results Summary

STAR has been very effective and productive:


1)
TOF, HLT, DAQ1k upgrades completed successfully


2)
200 GeV Au+Au collisions


-

Large acceptance
di
-
electron program started


-

Upsilon suppression vs. centrality and high statistics J/ψ v
2



-




3)

Beam Energy Scan


-

Systematic data of Au+Au collisions at 7.7/11.5/
19.6/27
/39/62.4GeV:


See some interesting results and data analysis in progress.


4)

Spin Physics


-

First W
±

A
L

results (2009) published;
di
-
jet A
LL

analysis


5)

High statistics, high quality data have been collected


-

pp 500 GeV FMS and low material Au+Au 200 GeV




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STAR

(3) STAR Future Planning Activities









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STAR

STAR Decadal Plan

Membership:
Helen
Caines
, Hank Crawford,
Jamie
Dunlop
(chair of heavy
-
ion task force
),
Olga
Evdokimov
,
Carl
Gagliardi

(chair
), Declan Keane, Thorsten
Kollegger
,
Bedanga


Mohanty
, Ernst Sichtermann,
Bernd
Surrow
(chair of spin task force
),
Thomas


Ullrich
,
Flemming

Videbaek

(chair of upgrades
), Wei
Xie
, Nu Xu, Zhangbu Xu


Issues discussed:


Science:

Properties of QGP at RHIC; QCD critical point;





Initial conditions; Proton helicity structure; Exotics



-

Trigger development for the next 10 years (enhance rare probe capabilities)



-

Additional detectors at the forward rapidity (
pA
,
ep
,
eA
)



-

Maintain and upgrade the existing detectors



-

New members for the collaboration


Status:

Phase
-
I exercise completed by Nov. 2010.




Document has been submitted to BNL and discussed at last PAC.




Live document, discussions continuous
, next update May 2012.






For Scientific Discovery
:

Compelling physics, Cost effective, Community


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STAR

eSTAR

Task Force

Membership
:

Subhasis

Chattopadhyay
,

Hank

Crawford,

Renee

Fatemi
,

Carl

Gargliardi
*,

Jeong
-
Hun

Lee,

Bill

Llope
,

Ernst

Sichtermann
,

Huan

Huang,

Thomas

Ullrich
,

Flemming

Videbaek
,

Anselm

Vossen
,

Wei

Xie
,

Qinghua

Xu,

Zhangbu

Xu


Ex
-
officio
:

B
.

Christie,

J
.

Dunlop,

O
.

Evdokimov
,

B
.

Mohanty
,

B
.

Surrow,

N
.

Xu



Charges
:

In

order

to

prepare

the

experiment

to

complement

the

ongoing

physics

programs

related

to

AA,

pA

and

pp

collisions

with

a

strong

ep

and

eA

program

by

an

additional

electron

beam

and

prepare

the

collaboration

to

participate

in

the

US

Nuclear

Physics

Long

Range

Planning

exercises

during

2012
-
2013
,

we

establish

the

eSTAR

Task

Force
.

This

task

force

will

be

in

function

during

the

next

three

years
.

The

main

charges

for

the

task

force

are
:


(1)
Identify

important

physics

measurements

and

assess

their

science

impact

during

the

eSTAR

era

(
2017
-
2020
)
.

Prepare

a

white

paper

or

an

updated

decadal

plan

including

physics

sensitivities

and

detailed

R&D

projects
.

(2)
With

(
1
)

in

mind

as

well

as

the

eRHIC

interaction

region

design(s
)

and

other

constraints,

identify

and

advise

STAR

Management

on

priorities

for

detector

R&D

projects

within

the

collaboration
.


(3)
Engage

the

collaboration

by

organizing

special

ep/eA

workshops,

document

the

progress

and

report

annually

to

the

collaboration
.

(4)
Work

with

the

STAR

management

and

the

EIC

task

force

(setup

by

the

BNL

management)

to

strengthen

the

physics

case(s
)

for

eSTAR

and

a

future

EIC

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STAR

(4)
Ongoing upgrades and issues











Compelling physics, Cost effective, Community


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STAR

STAR Upgrade
Timeline

*minimal configuration for Run 12 and completion before Run 13

Upgrade

Completion

Key Physics Measurements

FMS

Completed 2008

(a)
Trans. Asymmetry at forward
-
y

(b)
CGC

TPC DAQ1000

Completed 2009

Minimal

dead time, large data set

MRPC TOF

Completed 2010

Fast

PID in full
azimuthal

acceptance

Forward

GEM
Tracker

Summer 2011

*Ready for Run 12

Forward
-
y

W
±

for flavor separated
quark polarization

Heavy Flavor

Tracker

Summer 2013

Ready for Run 14

(a)
Precision

hadronic ID for charm
and Bottom hadrons

(b)
Charm and Bottom hadron energy
loss and flow

Muon

Telescope

Detector

Summer 2013

Ready for Run 14

(a)
High p
T

muon

trigger

(b)
Quarkonia

states

pp2pp’

Summer 2014

Ready for Run 15

(a)
DPE

processes

(b)
Search

for
glueball

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STAR



Forward GEM Tracker

FGT

HFT

1)
FGT: RHIC

CE
project

2)
Six light
-
weight triple
-
GEM disks

3)
New mechanical support structure

4)
Planned installation: Summer 2011

1)
Full charge
-
sign discrimination at high
-
p
T

2)
Design polarization performance of

70%
or better

to
collect at least 300pb
-
1


3)
Ready* for Run 12!



* minimal configuration



FGT
Quadrant

FGT

Quarter section Layout

HV layer

GEM layers (1
-
3
)

2mm apart!

No spacer!

2D readout
board

Readout
module

Packaged
APV chip

HV board

Terminator
board

Interconnect
board

Pressure
volume

Pressure
volume

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FGT

Schedule

I. Minimal
configuration

1)
Full FGT: 24 quarter sections / 6 disks (4 quarter sections per disk)

2)
Minimal
configuration:
4 disks with 3 quarter sections each, i.e. 50% of full
FGT system (24 quarter sections)

3)
4 disks, i.e. 4 space points are required for proper charge
-
sign discrimination



II. Schedule (draft)

1)
July
-
September
2011:

Quarter
section assembly and testing

2)
September 2011:



Disk
assembly and WSC integration

3)
October 2011:



Integration ESC
/ WSC / Beam pipe

/ Installation


Request RHIC cool down: January 1, 2012

in order to install as many FGT disks as possible


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SSD


IST


PXL

HFT

Heavy Flavor Tracker at STAR

FGT

1)
Identify heavy flavor hadron directly

2)
Precision measurement HF hadron energy
loss and collectivity

3)
R&D and Capital funds have been critical!

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Physics Goals for HFT

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Charm Baryon/Meson Ratios

Key for the production mechanism for Charm hadrons and their chemistry




Y. Oh,
et al
., PR
C79
, 044905(09);S.H. Lee,
et al.
, PRL
100
, 222301(08).

QGP

medium


C



pK
-

+


D
0



K
-

-
+

2
-
body collisions by
c

and
ud

3
-
body collisions by
c, u

and
d

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STAR

Heavy Flavor Physics

Λ
C
:
lowest charm baryon state,


~ 60μm


-

Hadro
-
chemistry with charm


-

Heavy flavor energy loss, meson vs. baryon effect

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STAR

STAR:
Muon

Telescope Detector


Muon

Telescope Detector (MTD) at STAR:

1)
MRPC technology;
μ
ε

~ 45%; cover ~60% azimuthally and |
y
| < 0.25

2)
TPC+TOF+MTD:
muon
/hadron enhancement factor ~ 10
2
-
3


3)
For high p
T

muon

trigger, heavy
quarkonia
, light vector mesons,
B

J/

+X

4)
China
-
India
-
STAR collaboration: build on the success of STAR MRPC TOF

TPC

beam pipe

TOF

EMC

MTD

magnet

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STAR

1)
Upsilon at RHIC:
unique, no regeneration, only initial
production

2)
MTD at STAR:
Υ

=>
μμ
,
unique, no
Bremsstrahlung

tails, clean separation of the
excited states

Study Medium Property Through
Υ

Υ

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STAR Project Management


BNL management
allocate total amount for
R&D, Capital and large
upgrade items


STAR management
discuss and distribute


STAR internal review

BNL review

More support from university groups for
operation activities, R&D efforts are needed

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Summary

1)
Recent upgrades (TOF, HLT) has provided STAR with new unique
opportunities


2)
The large acceptance of the mid
-
rapidity and the forward FGT, FMS
provides rich opportunities in spin physics


3)
BES runs are successful, systematic analysis emerging, final analysis
may point to future BES program at RHIC


4)
STAR has embarked on an evolving long term planning including
transitions to
eSTAR
. The whole collaboration is involved


5)
TPC issues: no sign of aging
has seen


6)
THE near term upgrades FGT, MTD and the HFT will ensure a vibrant
new STAR physics program in to the mid
-
term era at RHIC


7)
STAR management is working closely with BNL management on the
on
-
going upgrade projects

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STAR



FGT
Quadrant Problems and Solutions

-

Quarter section fully assembled and
operational (Cosmic
-
ray signal / 55Fe
signal) without spacer grid:


P1: GEM foils cannot be stretched
sufficiently to guarantee that GEM foils
separated by 2mm. Original design to
avoid efficiency loss.



Solution: Need for a spacer grid.
Order has been placed and expect full
quarter section assembly including
spacer grid.


P2: GEM foil frames are part of HV
distribution. The distance between HV
lines and metallic pins are ~1mm /

Difficulty in holding full HV (~4kV).



Solution: Need for non
-
metallic pins
providing sufficient strength / Likely G10
in addition to stretching bars

Spacer added

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FGT

Performance (4)

Cosmic
-
ray

tests:


1)
Test
-
stand completed
and fully
operational


2)
One
quarter section
fully read out (2 APV
boards) by final FEE
and
DAQ


3)
System
test data
available in STAR
software
framework


4)
Analysis
is ongoing!

Cosmic
-
Ray
Hit
distribution

GEM foil
quarter
section 5 not
connected