star future plans and upgrades
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STAR Future Plans and Upgrades
Hank CrawfordUCB/SSL
for the STAR Collaboration
AGS-Users-090605 1Crawford
Run 10Run 11Beyond
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
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For BES details, see http://drupal.star.bnl.gov/STAR/starnotes/public/sn0493
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 glueballsat central rapidity in pp2pp program with longitudinally polarized beams
pp at 500 and 200 GeV –Exploiting unique RHIC longitudinal and transverse polarization
Long Term Physics Goals
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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 motion
view 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
STAR Detector (current)
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MRPC ToF barrelMRPC ToF barrel100% ready for run 10100% ready for run 10
PMD
FPD
FMS
EMC barrel
EMC End Cap
DAQ1000DAQ1000
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
Particle Identification
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Reconstruct particles in full azimuthal acceptance of STAR!
Charm Bott
om
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
Run 10: BES: Search for signatures of a phase transition and a critical point.
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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
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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.
σx2 is the in-plane axis
σy2 is the out-of-plane
axis
ε = eccentricity
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
Run 10 : BES: Search for turn-off of new phenomena already established at higher RHIC energies
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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/nq vsmT scaling
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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
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
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
Run 10: 200 GeV program
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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
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
Run 10 200 GeVAuAu : Anti-Hypernuclei
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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 ZhangbuXu at this meeting
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 Gevrequires 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
Future inclusive jet ALL sensitivity
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• 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
Future: transverse spin forward γ + mid-rapidity jet
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Bacchetta et al., PRL 99, 212002
• 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
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
MxK+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
SoltanInstitue for Nuclear Studies, Warsaw, Poland
J.H. Lee
STAR Upgrades
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GMT – GEM Monitoring of tpcTracks - 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 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 - ??
GMT and FGT will be ready for Run 12
STAR Detector - future
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MRPC ToF barrelMRPC ToF barrel
100% ready for run 10100% ready for run 10
BBC
PMD
FPD
FMS
EMC barrelEMC End Cap
DAQ1000DAQ1000
FGT
Completed
Ongoing
MTD
R&DHFT
TPC
FHC
HLT
GEM Chambers to Monitor the TPC Tracking Calibrations (GMT)
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With increasing luminosity space charge distortion becomes major correction to TPC tracking.
David UnderwoodArgonne National LaboratoryGene VanBurenBrookhaven National LaboratoryJim ThomasLawrence Berkeley National LaboratoryJan BalewskiMITStephen Baumgart, Helen Caines, OanaCatu, Alexei Chikanian, Evan Finch, John Harris, Mark Heinz, Anders Knospe, Richard Majka, Christine Nattrass, JoernPutschke, SevilSalur, Jack Sandweiss, Nikolai SmirnovYale University
Proposalsubmitted 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.pdfSome 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
FGT Physics motivation - W program
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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
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Layout / GEM technology
SBIR proposal
(Phase I/II):
Established
commercial GEM
foil source (Tech-
Etch Inc.)
FNAL
testbeamofthree
prototype triple-
GEM
chambersincluding
APV25 chip readout
Performance meets
requirements!
Procurement and test offull full triple-GEM quarter triple-GEM quarter sectionsectioninprogress
New WEST support structure
HFTFGT
Residual [mm]
Residual: ~70μm
FGT Schedule and Milestones
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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
Forward Hadron Calorimeter (FHC)
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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
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
MUON Telescope Detector (MTD) at STAR
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Brookhaven National LaboratoryKen Asselta, Bill Christie, LijuanRuan, John Scheblein, Robert Soja,
ZhangbuXu 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 UniversitySaskiaMioduszewski
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.
MTD status
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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 m) and thin 0.4% Xo per layer
Physics Projections with HFT+TOF
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Charm collectivity => Medium properties, light flavor thermalization
Charm energy loss => Energy loss mechanisms, Medium properties
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
Summary
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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
Backup slides
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The Spin Puzzle
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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
Probing the Sea through Ws
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• 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 ALL
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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 ObservablesNijReconstructed for Different Bunch Patterns
Concurrent Measurements:
First look at “jet-like” events using FMS
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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 (NikolaPoljack – SPIN08)
MTD prototype tests
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•MTD hits: matched with real high pT tracks from TPCμz 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
MTD Multi-Resistive-Plate-Chamber (MRPC) cells
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Long MRPC Technology with double-end readout
HV: 6.3 KVgas mixture: 95% Freon + 5% isobutane
time resolution: ~ 60 psspatial resolution: ~ 1cm
efficiency: > 95%
GMT - GEM Monitoring of TPC Tracking
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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
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at ToF, cm
-1. 0. 1.0.
100.
200.
Distance in RPhi between hit at Tof and TPC track crossing Distance in RPhi between hit at Tof and TPC track crossing point (point (ToF, cm).ToF, 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 ~0 and ~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 pt/pt ~ s/s, need to correct distortions to sub mm level to maintain good momentum resolution.
GMT status:
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Proposalsubmitted 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.pdfSome 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, OanaCatu, Alexei Chikanian, Evan Finch, John Harris, Mark Heinz, Anders Knospe, Richard Majka, Christine Nattrass,
JoernPutschke, SevilSalur, Jack Sandweiss, Nikolai SmirnovYale University
Forward Heavy Mesons in FMS
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ω (from π0γ)
J/Ψ from e+e-
η from π0π0
FHC adds other mesons and baryons
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• 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
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
Fluctuation Observables
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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.
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