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STAR Future Plans and Upgrades. Run 10 Run 11 Beyond. Hank Crawford UCB/SSL for the STAR Collaboration. STAR Physics Goals for Run 10. search for QCD Critical point and for disappearance of signatures seen at top RHIC energy through Beam Energy Scan (BES) .

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star future plans and upgrades

STAR Future Plans and Upgrades

Run 10

Run 11


Hank Crawford


for the STAR Collaboration


star physics goals for run 10
STAR Physics Goals for Run 10
  • search for QCD Critical point and for disappearance of signatures seen at top RHIC energy through Beam Energy Scan (BES).
    • First energy scan from √sNN = 7.7 to 39 GeVAu+Au collisions
    • Combine with C-AD: machine development for √sNN = 5 GeVAu+Au collisions
  • study properties of the produced matter using200 GeVAuAu
    • Collective effects - heavy flavor dynamics
    • Correlations – ridge, parity violation
    • “full” jet dynamics – energy loss and modifications in medium
    • New particles and anti-particles

First AuAu run with full Time-of-Flight (TOF)

and full DAQ1000

SVT and SSD removed to minimize scattering and background

For BES details, see


star physics goals for run 11
STAR Physics Goals for Run 11

pp at 500 and 200 GeV –

Exploiting unique RHIC longitudinal and transverse polarization

Continue investigation of the origin of spin and the internal structure of the proton

using both 500 GeV and 200 GeV polarized pp collisions

study hydrodynamic behavior of matter at energy densities up to 50% higher than that achievable with Au+Au collisions in first run with U+U collisions to at 200 GeV

Study diffractive physics and search for glueballsat central rapidity

in pp2pp program with longitudinally polarized beams


long term physics goals
Long Term Physics Goals

Verify new state of matter (QGP) through measure of thermalization

Search for Chiral Symmetry Restoration

Quantify parton dynamics in nuclear collisions:

level of parity violation

mechanisms involved in energy loss

what correlations drive evolution

Determine internal structure of proton:

origin of spin and probe existence of orbital motion

view color force through Drell-Yan pairs

virtual quark content through heavy-meson production

Parton distribution to low-x

Parton dynamics – elastic and inelastic processes

Probe large mass objects via large rapidity separation correlations (Δη≈6)

Discover new particles and phenomena

and follow any leads from BES


s tar detector current
STAR Detector (current)

MRPC ToF barrel

100% ready for run 10

EMC barrel

EMC End Cap







Large variety of

Identified species

Is key to understanding




Full azimuthal particle identification!

γ, e, π, ρ, K, K*, p, φ, Λ, Δ, Ξ, Ω, D, ΛC, J/ψ, Υ ,ω…


particle identification
Particle Identification

Charm Bottom

Reconstruct particles in full azimuthal acceptance of STAR!


run 10 star tof all 120 trays ready
Run 10: STAR TOF – all 120 trays ready

TOF enables BES and HFT program

TOF 1/β cut rejects hadrons providing nearly complete and accurate electron identification for di-lepton program.

US project: Rice, UT-Austin, UCLA, BNL, LBNL

China project: USTC, Tsinghua, SINAP, IOPP Wuhan, IMP Langzhou


run 10 bes search for signatures of a phase transition and a critical point
Run 10: BES: Search for signatures of a phase transition and a critical point.

Elliptic & directed flow for charged particles and for identified protons and pions, which have been identified by many theorists as highly promising indicators of a “softest point” in the nuclear equation of state;

Azimuthally-sensitive femtoscopy, which adds to the standard HBT observables by allowing the tilt angle of the ellipsoid-like particle source in coordinate space to be measured; these measurements hold promise for identifying a softest point, and complements the momentum-space information revealed by flow measurements

Fluctuation measures, indicated by large jumps in the baryon, charge and strangeness susceptibilities, as a function of system temperature – the most obvious expected manifestation of critical phenomena.


azimuthally sensitive femtoscopy
Azimuthally-sensitive femtoscopy

ε = eccentricity

σx2 is the in-plane axis

σy2 is the out-of-plane


Freeze-out anisotropy from 2nd -order oscillations of HBT radii.  All measurements

are subject to ~30% systematic uncertainty. Inset shows hydro evolution of source

shape for an equation of state with (upper) and without (lower) softening due to

finite latent heat.



Sigma-dynamic (σdyn) is a measure of the event-by-event fluctuations in the particle ratio. This fluctuation is expected to be maximized at the CP.



Results for K/p are compared to models to remove to general trends.

Expected error with 100 k central events


run 10 bes search for turn off of new phenomena already established at higher rhic energies
Run 10 : BES: Search for turn-off of new phenomena already established at higher RHIC energies

Constituent-quark-number scaling of v2 , indicating partonic degrees of freedom;

Hadron suppression in central collisions as characterized by the ratio RCP ;

Untriggered pair correlations in the space of pair separation in azimuth and pseudorapidity, which elucidate the ridge phenomenon;

Local parity violation in strong interactions, an emerging and important RHIC discovery in its own right, is generally believed to require deconfinement, and thus also is expected to turn-off at lower energies.


v2 n q vs m t scaling
V2/nq vsmT scaling

Elliptic flow per constituent quark versus transverse mass per constituent quark for Au + Au collisions at 200 GeV at RHIC.

See talk by Xin Dong

at this meeting


search for parity violation

L or B

Search for Parity Violation

The separation between the same-charge and opposite-charge correlations.

- Strong EM fields

- De-confinement and Chiral

symmetry restoration

See talk by Xin Dong at this meeting


qcd phase diagram
QCD Phase Diagram

STAR can trace

trajectories by measurement of

variety of particle yields

as a function of energy

T and μ are then calculated from

the set of yields

A schematic representation of the QCD Phase Diagram. The location of the critical point, the separation between the 1st-order transition and chemical freeze-out, and the focusing of the event trajectories towards the critical point, are not based on specific quantitative predictions, but are all chosen to illustrate plausible possibilities.


run 10 200 gev program
Run 10: 200 GeV program

γ-hadron correlations: a “golden probe” of parton energy loss in the medium

Heavy Flavor signals : understand energy loss mechanisms – radiative, collisional




Projection of uncertainties in

Upsilon(1S) RAA for two sets of

integrated luminosity.


full jet reconstruction in heavy ion collisions at star

~ 21 GeV

STAR preliminary

pt per grid cell [GeV]



Full-Jet Reconstruction in heavy-ion collisions at STAR

AuAu 10%

  • Extended the kinematical reach to study jet quenching phenomena to jet energies > 40 GeV in central Au+Au collisions at RHIC
  • Strong evidence of broadening in the jet energy profile observed
  • Significant suppression in the di-jet coincidence seen in central Au+Au collisions;suggests strong quenching effects accessible in the current kinematics at RHIC

Full-jet reconstruction measurements will greatly benefit from increased statistics to further extend the kinematical reach and quantitatively measure partonic energy loss phenomena at RHIC


run 10 200 gev auau anti hypernuclei
Run 10 200 GeVAuAu : Anti-Hypernuclei



Coalescence calculations

show we will have measurable

sample of anti-alphas and

perhaps double-Λ-hypernuclei

Upper panels show the invariant mass distribution of helium3 + pion in Au+Au collisions at 200 GeV. Open circles represent the signal candidate distributions, solid black lines are background distributions. Lower panels show the helium3 candidates Z (log((dE/dx)measured/(dE/dx)expected)) distribution from the same data set.

See talks by Xin Dong and ZhangbuXu at this meeting


run 11 pp goals
Run 11 pp goals

1. Measure parity-violating AL for mid-rapidity W production at 500 GeV

requires 15 pb-1 at P>50%

2. Measure xF dependence of π0 AN and forward jets at 500 Gev

requires 6.5 pb-1 at P>50%

3. Begin to Measure γ-jet AN at 200 GeV to see color through sign change wrt SIDIS

requires 15 pb-1 at P>65% (full sample required is 30 pb-1)

4. Measure AN for “full” forward jets to separate Collins and Sivers components

requires same 15 pb-1 as 3 with FHC

5. Complete map of x dependence of gluon helicity contribution to spin

80 pb-1 required; Run11 increment awaits Run9 analysis


future inclusive jet a ll sensitivity
Future inclusive jet ALL sensitivity

Projected sensitivities:

Run 9 & future 500 GeV running

Projected improvement in xΔg from Run 9

  • Goal for the current 200 GeV run:
    • 50 pb-1 @ 60% pol – reduce ALL uncertainties a factor of ~4
    • Will provide much stronger constraints on gluon polarization
  • Goal for future 500 GeV running:
    • 300 pb-1 @ 70% pol
    • Extend precision determination to lower xg

See Carl Gagliardi talk this meeting


future transverse spin forward mid rapidity jet
Future: transverse spin forward γ + mid-rapidity jet

Bacchetta et al., PRL 99, 212002

See Carl Gagliardi talk this meeting

  • Conventional calculations predict the asymmetry to have the same sign in SIDIS andγ+jet
  • Calculations that account for the repulsive interactions between like color charges predict opposite sign
  • Critical test of our basic theoretical understanding


pp2pp future physics with tagged forward protons elastic and inelastic processes
PP2PP: Future Physics with Tagged Forward Protons Elastic and Inelastic Processes

Elastic Scattering: Roman Pots only

Central Production: RP + ToF; Tracks in the TPC

Phase II - install RPs so that we can run with STAR without special conditions. RPs need to be between DX-D0 magnets.

In Phase II hundreds of millions of events can be acquired by running in parallel with STAR

central production in double pomeron exchange
Central Production in Double Pomeron Exchange

H. Spinka

Argonne National Laboratory, USA

R. Gill, W. Guryn*, J. Landgraf, T.A. Ljubičič, D. Lynn, R. Longacre,

P. Pile, S. Tepikian, K. Yip

Brookhaven National Laboratory, USA

Y. Gorbunov,

Creighton University, Omaha, NE 68178

I. G. Alekseev, L. I. Koroleva, A. Manaenkova, B. V. Morozov, D. N. Svirida

ITEP, Moscow, Russia

S. Bueltmann, I. Koralt,S. Kuhn, D. Plyku

Old Dominion University, Norfolk, USA

G. Eppley, W. J. Llope

Rice Univ., Houston


SoltanInstitue for Nuclear Studies, Warsaw, Poland

J.H. Lee

Glueball possible decay channels:




Mx (K+K+K-K-

star upgrades
STAR Upgrades

GMT – GEM Monitoring of tpcTracks - improve TPC tracking

FGT – Forward GEM Tracker - provide forward tracking for 500 GeV pp measurements of anti-quark contribution to spin

GMT and FGT will be ready for Run 12

HFT – Heavy Flavor Tracker - provide low-mass inner tracking to allow heavy-quark measurements probing thermalization at low pT – Run 14?

FHC – Forward HadronCalorimeter - provide forward hadron identification to enable “full” jet reconstruction in separating Collins and Sivers function – Run 10?

MTD – MuonTelescope Detector - provide muon identification at mid-rapidity to enable charm suppression study – Run 13?

HLT – High Level Trigger - provide online-tracking trigger – Run 11?

FMP – Forward Meson Preshower – to allow π0 identification up to 100 GeV and beyond - ??


star detector future
STAR Detector - future


EMC barrel

MRPC ToF barrel

100% ready for run 10

EMC End Cap















gem chambers to monitor the tpc tracking calibrations gmt
GEM Chambers to Monitor the TPC Tracking Calibrations (GMT)
  • David Underwood
  • Argonne National Laboratory
  • Gene VanBuren
  • Brookhaven National Laboratory
  • Jim Thomas
  • Lawrence Berkeley National Laboratory
  • Jan Balewski
  • MIT
  • Stephen Baumgart, Helen Caines, OanaCatu, Alexei Chikanian, Evan Finch,
  • John Harris, Mark Heinz, Anders Knospe, Richard Majka, Christine Nattrass,
  • JoernPutschke, SevilSalur, Jack Sandweiss, Nikolai Smirnov
  • Yale University

With increasing luminosity space charge distortion becomes major

correction to TPC tracking.

Small GEM cells

Replace TOF slat to

verify TPC track pointing

  • Proposalsubmitted Oct. 15, 2007
  • Reviewed in Star ~ Oct., 2008
  • “The committee therefore recommends unanimously to accept the proposal, and to construct and install the detectors in a timely schedule.”
  • Updated Proposal Oct., 2008
  • Some R&D funding available FY2009
  • Schedule: ~2 years to construct and install. Tied to developments for FGT
  • Cost estimate: ~$140k


fgt physics motivation w program


FGT Physics motivation - W program
  • Quark / Anti-Quark Polarization - W production
  • Key signature: High pT lepton (e-/e+) (Max. MW/2) - Selection of W-/W+ : Charge sign discrimination of high pT lepton - STAR FGT
  • Required: Lepton/Hadron discrimination - STAR EEMC and FGT

Full STAR detector W signal and QCD background simulation completed


fgt layout gem technology development


Residual: ~70μm

Residual [mm]

FGT Layout/ GEM Technology Development
  • Layout / GEM technology
  • SBIR proposal (Phase I/II): Established commercial GEM foil source (Tech-Etch Inc.)
  • FNAL testbeamofthree prototype triple-GEM chambersincludingAPV25 chip readout
  • Performance meets requirements!



Procurement and test offull triple-GEM quarter sectioninprogress

New WEST support structure


fgt schedule and milestones


FGT Schedule and Milestones
  • Overview
    • Goal: Complete FGT construction in ~fall 2010 followed by full system test and subsequent full installation in ~summer 2011⇒ Ready for anticipated first long 500GeV polarized pp run in FY12
    • Review: Successful review January 2008 / Beginning of construction funds FY08
    • Cost estimate / planning / milestones: R&D and pre-design work: FY07 / FY08
      • Triple-GEM Detector: Complete prototype tested (Bench and FNAL testbeam)
      • Front-End Electronics (FEE) System: Complete prototype tested / FEE design completed
      • Data Acquisition (DAQ) System: Layout exists based on similar DAQ sub-detector systems with extensive experience (ANL/IUCF)
      • Mechanical pre-design completed: Triple-GEM detector and new support structure
      • GEM foil development: Successful development of industrially produced GEM foils through SBIR proposal in collaboration with Tech-Etch Inc. (BNL, MIT, Yale University)
    • Critical: Timely FGT DOE construction funds: FY08, FY09 and FY10

Bernd Surrow


forward hadron calorimeter fhc
Forward Hadron Calorimeter (FHC)

Real jet physics with FMS + FHC (EM+had)

Lambdanπ0 (+other hadons possible)

Photon (isolation)

= recycle

BNL-AGS-E864 hadron calorimeter detectors

Refurbished and used by PHOBOS

Estimated statistical precision for uncertainty in analyzing power for p+pjet + X at s = 200 GeV.


fhc timeline
FHC Timeline
  • Proposal review in STAR – expect approval soon
  • If approved, we can install for RHIC run 10 
    • move entire stacks from PHOBOS (IP10) to STAR assembly building after run 9 ends
    • move one entire stack to “north side” using tunnel access doors.
    • unstack/restack in place for “south side” due to no tunnel access.



high level trigger hlt examples of physical potential
High Level Trigger (HLT) Examples of Physical Potential
  • Heavy flavor measurements.
  • Physics addressed : the mechanism of fast thermal equilibration.
  • Information used in trigger : dE/dx and tracking from TPC & HFT, High tower from BEMC and/or TOF hits. 
  • Large pt spectra and correlation for identified particles.
  • Physics addressed : Energy loss, Hadronization etc.
  • Information used in trigger : tracking from TPC, TOF.
  • Anti-matter production.
  • Physics addressed : Understanding the fundamentals of our universe.
  • Information used in trigger : dE/dx from TPC, High tower from BEMC.

Run 9 p+p 200 GeV, May 19 - 25

muon telescope detector mtd at star
MUON Telescope Detector (MTD) at STAR

To detect charged particles that do not range out in the return steel of the STAR magnet – primarily muons – and use their

TPC momentum and MTD/TOF velocity to

reconstruct quarkonia.

Brookhaven National Laboratory

Ken Asselta, Bill Christie, LijuanRuan, John Scheblein, Robert Soja, ZhangbuXu

University of California, Berkeley

Hank Crawford, Jack Engelage

Rice University

Geary Eppley, Bill Llope, Ted Nussbaum

University of Science and Technology of China

Hongfang Chen, Cheng Li, Yongjie Sun, Zebo Tang

Shanghai Institute of Applied Physics

Xiang-Zhou Cai, Fu Jin, Yu-Gang Ma, Chen Zhong

Texas A&M University


University of Texas -- Austin

Jerry Hoffmann, Jo Schambach

Tsinghua University

Yi Wang, Xiaobin Wang

Yale University

Guoji Lin, Richard Majka


mtd status
MTD status

Prototypes tested in runs 8 and 9

Expect full proposal in FY10

Installation for Run 13






HFT upgrade in STAR

  • Heavy quark is one of the ideal probes to quantify the properties of the hot dense medium created in relativistic heavy ion collisions.
  • Heavy quark program at RHIC/STAR is underway. Present physics conclusions are rather qualitative.
  • With detector upgrades, STAR will be able to perform precision measurements on open charm and quarkonia measurements in p+p, p(d)+A, and A+A collisions.
  • Precision measurements via direct reconstruction of displayed vertices and particle identification over 2pi covering low and high pT
  • SSD (existing double sided strip detector) is

outer layer

  • IST is a layer of silicon strip
  • PIXEL is 2 inner layers of high resolution

Pixel (MAPS) (18*18 mm) and thin 0.4% Xo

per layer

~ 30 microns pointing resolution at 0.7 GeV/c

~ 30 microns secondary vertex resolution (large p)


physics projections with hft tof
Physics Projections with HFT+TOF

Charm energy loss => Energy loss mechanisms, Medium properties

Charm collectivity => Medium properties, light flavor thermalization


hft status
HFT status
  • R&D for the pixel sensors, readout and support structure has been successfully carried out over several years.
  • Design and layout mature.
  • Technical driven schedule for project
  • Received CD-0 Feb. 2009
  • Aim for CD-1 review in Sept 2009
  • Engineering prototype installed for run-12
  • Completed for run-14



Run 10 AuAu : BES has high international interest

BES should provide many clues to onset of new state of matter

New TOF and DAQ100 will lead to much improved understanding

of highest RHIC energy collisions including jet reconstruction

and di-lepton signatures with energy loss for correlated particles

Run 11 pp at 500 and 200 GeV:

clear separation of Collins and Sivers effects

mid-rapidity W signals

gamma-jet AN and di-jet ALL

Run 12: GMT and FGT will give sea-quark spin contribution through

forward and mid-rapidity W+W-

Future includes HFT and understanding of thermalization


the spin puzzle

A future challenge

The Spin Puzzle

The proton is viewed as being a “bag” of

bound quarks and gluons interacting via QCD

Spins + orbital angular momentum need

to give the observed spin 1/2 of proton

Fairly well measured

only ~30% of spin

Being measured



probing the sea through ws
Probing the Sea through Ws
  • Reconstruct Ws through e+ ande- decay channels
  • V-A coupling leads to perfect spin separation
  • Neutrino helicity gives preferred direction in decay

Measure parity violating single helicity asymmetry AL

(Helicity flip in one beam while averaging over the other)


experimentally measuring a ll
Experimentally Measuring ALL

Concurrent Measurements:

Numbers of ObservablesNijReconstructed for Different Bunch Patterns

Relative Luminosity R from BBC Coincidence Rates for different Bunch Patterns

Polarization of Beams (magnitude from CNI Polarimeters, direction of polarization vector from combination CNI Polarimeters, BBC)


first look at jet like events using fms
First look at “jet-like” events using FMS

Event selection done with:

  • >15 detectors with energy > 0.4GeV in the event
  • (no single pions in the event)
  • cone radius = 0.5 (eta-phi space)
  • “Jet-like” pT > 1 GeV/c ; xF > 0.2
  • 2 perimeter fiducial volume cut (small/large cells)

ANjet is only sensitive to Sivers

Hadron correlation with in jet

for Collins effect


arXiv:0901.2828 (NikolaPoljack – SPIN08)

mtd prototype tests
MTD prototype tests
  • MTD hits: matched with real high pT tracks from TPC
  • μz distribution has two components:
  • narrow (muon) and broad (hadron)
  • spatial resolution (narrow Gaussian)
  • ~10 cm at pT> 2 GeV
  • narrow to broad ratio is ~2; can be
  • improved with dE/dx and TOF cut


mtd multi resistive plate chamber mrpc cells
MTD Multi-Resistive-Plate-Chamber (MRPC) cells

Long MRPC Technology with double-end readout

HV: 6.3 KV

gas mixture: 95% Freon + 5% isobutane

time resolution: ~ 60 ps

spatial resolution: ~ 1cm

efficiency: > 95%


gmt g em m onitoring of tpc t racking
GMT - GEM Monitoring of TPC Tracking
  • With increasing luminosity space charge distortion becomes major correction to TPC tracking.
  • Exciting new physics opportunities will become available in STAR with higher luminosity
  • Many of these rely on precision tracking in the TPC.
    • Separation of J/Ψ states,
    • high Pt tracking for jet studies , upsilon, W
    • possible tracking triggers (fast filters)
    • good pointing resolution to the silicon detectors at inner radius for charm reconstruction.


gmt detail
GMT detail

Distance in RPhi between hit at Tof and TPC track crossing point (DToF, cm).

Constraining corrections using a measurement at outer radius is best done at h~0 and h~1

Z at ToF radius, cm

40x1026 cm-2 * s-1


1026 cm-2 * s-1

at 0.5T field, a 5(10) GeV/c track crossing from the inner TPC pad row to the outer pad row will have a sagitta of 6.3 (3.2) mm

~twice that if primary vtx and/or PIXEL is used in fit

Since Dpt/pt ~ Ds/s, need to correct distortions to sub mm level to maintain good momentum resolution.



-1. 0. 1.

D at ToF, cm


gmt status
GMT status:

Proposal to Install GEM Chambers to Monitor the TPC Tracking Calibrations (GMT)

David Underwood

Argonne National Laboratory

Gene VanBuren

Brookhaven National Laboratory

Jim Thomas

Lawrence Berkeley National Laboratory

Jan Balewski


Stephen Baumgart, Helen Caines, OanaCatu, Alexei Chikanian, Evan Finch,

John Harris, Mark Heinz, Anders Knospe, Richard Majka, Christine Nattrass,

JoernPutschke, SevilSalur, Jack Sandweiss, Nikolai Smirnov

Yale University

  • Proposalsubmitted Oct. 15, 2007
  • Reviewed in Star ~ Oct., 2008
  • “The committee therefore recommends unanimously to accept the proposal, and to construct and install the detectors in a timely schedule.”
  • Updated Proposal Oct., 2008
  • Some R&D funding available FY2009
  • Schedule: ~2 years to construct and install. Tied to developments for FGT
  • Cost estimate: ~$140k


forward heavy mesons in fms
Forward Heavy Mesons in FMS

FHC adds other mesons and baryons

ω (from π0γ)

η from π0π0

J/Ψ from e+e-


photon jet at star
Photon-Jet at STAR

If photon goes to FMS

We benefit from ALL

But we may lose from pT

Jet: |η|<0.8,

pT>5 GeV

Photon: 1.08<η<2.0,

pT>7 GeV

back to back in plane

• Clean probe of qginteraction

• Signal requires more luminosity than dijet measurements: em* s vs. s* s

• Want to focus on asymmetric partonic collisions: high-x quark and low-x gluons with the detected in the direction of the incident quark here the cross section and asymmetry is maximized

• Shower Maximum Detector (SMD) shower shape & Monte Carlo normalization analysis in progress



fluctuation observables
Fluctuation Observables

If we pass through a QCD phase transition, we expect a change in the number

of degrees of freedom and a corresponding change in particle number fluctuations.

We measure the number of pions, kaons, protons, etc in each event and form ratios

to cancel volume effects. We then look at fluctuations in the event-by-event ratios

as a function of collision energy to find the critical point for QGP<->hadron gas transition.