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STAR Future Plans and Upgrades

Hank CrawfordUCB/SSL

for the STAR Collaboration

AGS-Users-090605

Run 10Run 11Beyond

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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 GeV Au+Au collisions

– Combine with C-AD: machine development for √sNN = 5 GeV Au+Au collisions

• study properties of the produced matter using 200 GeV AuAu – 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

AGS-Users-090605

For BES details, see http://drupal.star.bnl.gov/STAR/starnotes/public/sn0493

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STAR Physics Goals for Run 11

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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

Continue investigation of the origin of spin and the internal structure of the protonusing both 500 GeV and 200 GeV polarized pp collisions

Study diffractive physics and search for glueballs at central rapidity in pp2pp program with longitudinally polarized beams

pp at 500 and 200 GeV –Exploiting unique RHIC longitudinal and transverse polarization

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Long Term Physics Goals

AGS-Users-090605

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

Search for Chiral Symmetry Restoration

Quantify parton dynamics in nuclear collisions:level of parity violationmechanisms involved in energy losswhat correlations drive evolution

Determine internal structure of proton:origin of spin and probe existence of orbital motionview color force through Drell-Yan pairsvirtual quark content through heavy-meson productionParton distribution to low-xParton 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

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STAR Detector (current)

AGS-Users-090605

MRPC ToF barrel100% ready for run 10

PMD

FPD

FMS

EMC barrel

EMC End Cap

DAQ1000

Complete

Ongoing

TPC

FTPC

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

BBC

Large variety ofIdentified speciesIs key to understanding

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Particle Identification

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Reconstruct particles in full azimuthal acceptance of STAR!

Charm Bott

om

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Run 10: STAR TOF – all 120 trays ready

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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

TOF enables BES and HFT program

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

AGS-Users-090605

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.

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Azimuthally-sensitive femtoscopy

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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.

€

ε =σx2

€

ε =(σ y2 − σ x

2 )/(σ y2 +σ x

2 )

σx2 is the in-plane axis

σy2 is the out-of-plane

axis

ε = eccentricity

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Fluctuations

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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.

Expected error with 100 k central eventsResults for K/p are compared to models to remove to general trends.

K/p K/p

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

AGS-Users-090605

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.

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V2/nq vs mT scaling

AGS-Users-090605

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

See talk by Xin Dongat this meeting

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Search for Parity Violation

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L or B

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

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QCD Phase Diagram

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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.

STAR can tracetrajectories by measurement ofvariety of particle yieldsas a function of energy

T and μ are then calculated fromthe set of yields

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Run 10: 200 GeV program

AGS-Users-090605

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

Quarkonia:

Projection of uncertainties in Upsilon(1S) RAA for two sets of integrated luminosity.

J/Ψ ϒ

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

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Full-Jet Reconstruction in heavy-ion collisions at STAR

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ϕη

pt p

er g

rid

cel

l [G

eV

]

STAR preliminary

~ 21 GeV

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

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Run 10 200 GeV AuAu : Anti-Hypernuclei

AGS-Users-090605

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.

Coalescence calculationsshow we will have measurablesample of anti-alphas andperhaps double-Λ-hypernuclei

Hypertriton ANTI-hypertriton

See talks by Xin Dong and Zhangbu Xu at this meeting

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Run 11 pp goals

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1. Measure parity-violating AL for mid-rapidity W production at 500 GeVrequires 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 SIDISrequires 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 componentsrequires same 15 pb-1 as 3 with FHC

5. Complete map of x dependence of gluon helicity contribution to spin80 pb-1 required; Run11 increment awaits Run9 analysis

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Future inclusive jet ALL sensitivity

AGS-Users-090605

• 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

Projected improvement in xΔg from Run 9

Projected sensitivities:Run 9 & future 500 GeV running

See Carl Gagliardi talk this meeting

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Future: transverse spin forward γ + mid-rapidity jet

AGS-Users-090605

Bacchetta et al., PRL 99, 212002

• Conventional calculations predict the asymmetry to have the same sign in SIDIS and γ+jet

• Calculations that account for the repulsive interactions between like color charges predict opposite sign

• Critical test of our basic theoretical understanding

See Carl Gagliardi talk this meeting

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

Glueball possible decay channels:Mx Mx Mx K+ K-

Mx ( K+ K+ K-K-

H. SpinkaArgonne National Laboratory, USA

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

P. Pile, S. Tepikian, K. YipBrookhaven 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. PlykuOld Dominion University, Norfolk, USA

G. Eppley, W. J. LlopeRice Univ., Houston

A.Sandacz

Soltan Institue for Nuclear Studies, Warsaw, Poland

J.H. Lee

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STAR Upgrades

AGS-Users-090605

GMT – GEM Monitoring of tpc Tracks - improve TPC trackingFGT – Forward GEM Tracker - provide forward tracking for 500 GeV pp measurements of anti-quark contribution to spin

HFT – Heavy Flavor Tracker - provide low-mass inner tracking to allow heavy-quark measurements probing thermalization at low pT – Run 14?FHC – Forward Hadron Calorimeter - provide forward hadron identification to enable “full” jet reconstruction in separating Collins and Sivers function – Run 10?MTD – Muon Telescope 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 - ??

GMT and FGT will be ready for Run 12

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STAR Detector - future

AGS-Users-090605

MRPC ToF barrel100% ready for run 10

BBC

PMD

FPD

FMS

EMC barrelEMC End Cap

DAQ1000

FGT

Completed

Ongoing

MTD

R&DHFT

TPC

FHC

HLT

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GEM Chambers to Monitor the TPC Tracking Calibrations (GMT)

AGS-Users-090605

With increasing luminosity space charge distortion becomes major correction to TPC tracking.

David UnderwoodArgonne National Laboratory

Gene VanBurenBrookhaven National Laboratory

Jim ThomasLawrence Berkeley National Laboratory

Jan BalewskiMIT

Stephen Baumgart, Helen Caines, Oana Catu, Alexei Chikanian, Evan Finch, John Harris, Mark Heinz, Anders Knospe, Richard Majka, Christine Nattrass,

Joern Putschke, Sevil Salur, Jack Sandweiss, Nikolai SmirnovYale UniversityProposal submitted 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 http://hepwww.physics.yale.edu/star/upgrades/GEM/GMT-2.pdf Some R&D funding available FY2009

Schedule: ~2 years to construct and install. Tied to developments for FGTCost estimate: ~$140k

Small GEM cells Replace TOF slat to verify TPC track pointing

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FGT Physics motivation - W program

AGS-Users-090605

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

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FGT Layout/ GEM Technology Development

AGS-Users-090605

Layout / GEM technology

SBIR proposal

(Phase I/II):

Established

commercial GEM

foil source (Tech-

Etch Inc.)

FNAL testbeam of

three prototype

triple-GEM

chambers including

APV25 chip readout

Performance meets

requirements!

Procurement and test of full triple-GEM quarter section

in progress

New WEST support structure

HFTFGT

Residual [mm]

Residual: ~70μm

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FGT Schedule and Milestones

AGS-Users-090605

Bernd Surrow

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

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Forward Hadron Calorimeter (FHC)

AGS-Users-090605

Estimated statistical precision for uncertainty in analyzing power for p+pjet + X at s = 200 GeV.

BNL-AGS-E864 hadron calorimeter detectorsRefurbished and used by PHOBOS

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

Lambdanπ0 (+other hadons possible)

Photon (isolation)

= recycle

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FHC Timeline

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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 • 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

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MUON Telescope Detector (MTD) at STAR

AGS-Users-090605

Brookhaven National LaboratoryKen Asselta, Bill Christie, Lijuan Ruan, John Scheblein, Robert

Soja, Zhangbu Xu University of California, BerkeleyHank Crawford, Jack Engelage

Rice UniversityGeary Eppley, Bill Llope, Ted Nussbaum

University of Science and Technology of ChinaHongfang Chen, Cheng Li, Yongjie Sun, Zebo Tang

Shanghai Institute of Applied PhysicsXiang-Zhou Cai, Fu Jin, Yu-Gang Ma, Chen Zhong

Texas A&M UniversitySaskia Mioduszewski

University of Texas -- Austin Jerry Hoffmann, Jo Schambach

Tsinghua UniversityYi Wang, Xiaobin Wang

Yale University Guoji Lin, Richard Majka

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 toreconstruct quarkonia.

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MTD status

AGS-Users-090605

Prototypes tested in runs 8 and 9

Expect full proposal in FY10

Installation for Run 13

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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

2 30.5

~ 30 microns pointing resolution at 0.7 GeV/c

~ 30 microns secondary vertex resolution (large p)

SSD (existing double sided strip detector) is outer layerIST 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

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Physics Projections with HFT+TOF

AGS-Users-090605

Charm collectivity => Medium properties, light flavor thermalization

Charm energy loss => Energy loss mechanisms, Medium properties

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HFT status

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• 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

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Summary

AGS-Users-090605

Run 10 AuAu : BES has high international interestBES should provide many clues to onset of new state of matter

New TOF and DAQ100 will lead to much improved understandingof highest RHIC energy collisions including jet reconstructionand di-lepton signatures with energy loss for correlated particles

Run 11 pp at 500 and 200 GeV: clear separation of Collins and Sivers effectsmid-rapidity W signalsgamma-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

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Backup slides

AGS-Users-090605

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The Spin Puzzle

AGS-Users-090605

€

1

2=1

2ΔΣ+ Lq

z + ΔG + Lgz

Fairly well measuredonly ~30% of spin

A future challenge

The proton is viewed as being a “bag” of bound quarks and gluons interacting via QCD

Spins + orbital angular momentum needto give the observed spin 1/2 of proton

Being measuredat RHIC

€

ΔΣ= (Δu+ Δd + Δs+ Δu + Δd + Δs +L )dx∫

€

ΔG = Δgdx∫

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Probing the Sea through Ws

AGS-Users-090605

• Reconstruct Ws through e+

and e- 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)

€

u+ d →W +→ e+ + ν

€

u + d→W −→ e− + ν

€

ALW +

∝Δu(x1)d (x2) −Δd (x1)u(x2)

€

ALW− ∝Δd(x1)u (x2) −Δu (x1)d(x2)

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Experimentally Measuring ALL

AGS-Users-090605

€

€

ALL =1

P1P2

(N ++ + N−−) − R(N +− + N−+)

(N ++ + N−−) + R(N +− + N−+)

€

R =L++ + L−−

L+− + L−+

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)

Numbers of Observables Nij Reconstructed for Different Bunch Patterns

Concurrent Measurements:

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First look at “jet-like” events using FMS

AGS-Users-090605

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 jetfor Collins effect

arXiv:0901.2828 (Nikola Poljack – SPIN08)

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MTD prototype tests

AGS-Users-090605

•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 GeVnarrow to broad ratio is ~2; can be improved with dE/dx and TOF cut

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MTD Multi-Resistive-Plate-Chamber (MRPC) cells

AGS-Users-090605

Long MRPC Technology with double-end readout

HV: 6.3 KVgas mixture: 95% Freon + 5% isobutane

time resolution: ~ 60 psspatial resolution: ~ 1cm

efficiency: > 95%

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GMT - GEM Monitoring of TPC Tracking

AGS-Users-090605

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.

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GMT detail

AGS-Users-090605

D at ToF, cm

-1. 0. 1.0.

100.

200.

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

Z at ToF radius, cm

1026 cm-2 * s-1

40x1026 cm-2 * s-1

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

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GMT status:

AGS-Users-090605

Proposal submitted Oct. 15, 2007Reviewed 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 http://hepwww.physics.yale.edu/star/upgrades/GEM/GMT-2.pdf Some R&D funding available FY2009

Schedule: ~2 years to construct and install. Tied to developments for FGTCost estimate: ~$140k http://hepwww.physics.yale.edu/star/upgrades/GEM/GMT-2.pdf

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

David UnderwoodArgonne National Laboratory

Gene VanBurenBrookhaven National Laboratory

Jim ThomasLawrence Berkeley National Laboratory

Jan BalewskiMIT

Stephen Baumgart, Helen Caines, Oana Catu, Alexei Chikanian, Evan Finch, John Harris, Mark Heinz, Anders Knospe, Richard Majka, Christine Nattrass,

Joern Putschke, Sevil Salur, Jack Sandweiss, Nikolai SmirnovYale University

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Forward Heavy Mesons in FMS

AGS-Users-090605

ω (from π0γ)

J/Ψ from e+e-

η from π0π0

FHC adds other mesons and baryons

CrawfordAGS-Users-090605

• Clean probe of qg interaction• 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

Jet: |η|<0.8, pT>5 GeV

Photon: 1.08<η<2.0, pT>7 GeV

back to back in plane

If photon goes to FMSWe benefit from ALL

But we may lose from pT

Photon-Jet at STAR

D.Staszak

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Fluctuation Observables

AGS-Users-090605

If we pass through a QCD phase transition, we expect a change in the numberof 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 ratiosas a function of collision energy to find the critical point for QGP<->hadron gas transition.