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Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
John Harris (Yale)
A Comprehensive New Detector for RHIC II Physics
for
L. Bland, M. Calderon, P. Steinberg, T. Ullrich (BNL)
H. Caines, J.W. Harris, C. Markert, N. Smirnov (Yale)
R. Bellwied, C. Pruneau, S. Voloshin (Wayne State)
M. Lisa, D. Magestro (Ohio State)
B. Surrow (MIT)
R. Lacey (Stony Brook)
S. Margetis (Kent State)
G. Paic (UNAM Mexico)
T. Nayak (VECC Calcutta)(forming) an “exploratory working group” on a comprehensive new
detector for RHIC II physics
…. (LBNL)?
presented at RHIC Planning Meetingpresented at RHIC Planning MeetingBNL on 4 Dec 2003BNL on 4 Dec 2003
Comprehensive RHIC II DetectorComprehensive RHIC II Detector
Ideas for a Ideas for a Comprehensive New DetectorComprehensive New Detector for for In-Depth Study of the In-Depth Study of the QGPQGP, , Initial ConditionsInitial Conditions
and and Spin PhysicsSpin Physics at RHIC II at RHIC II
R. Bellwied, J.W. Harris, N. Smirnov, R. Bellwied, J.W. Harris, N. Smirnov, P. Steinberg, B. Surrow, and T. UllrichP. Steinberg, B. Surrow, and T. Ullrich
Statement of Interest document and Yale Workshop (April 16-17, 2004)at
http://star.physics.yale.edu/users/harris/
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
PHOBOS BRAHMS
Relativistic Heavy Ion Collider Facility
RHIC AuAu Design Parameters:Beam Energy = 100 GeV/u No. Bunches = 57 No. Ions /Bunch = 1 109
Tstore = 10 hours
Lave = 2 1026 cm-2 sec-1
RHIC
AGS
LINACBOOSTER
TANDEMS
Pol. Proton Source
High Int. Proton Source9 GeV/uQ = +79
1 MeV/uQ = +32
HEP/NP
g-2
U-lineBAF (NASA)
STARPHENIX
RHIC II AuAu Parameters:Beam Energy = 100 GeV/u No. Bunches = 112 Lave = 8 1027 cm-2 sec-1
RHIC II pp Parameters:Beam Energy = 250 GeV/u Lave = 5 1032 cm-2 sec-1
RHIC pp Design Parameters:Beam Energy = 250 GeV/u Lave = 1.5 1032 cm-2 sec-1
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Luminosities for AuAu at RHIC & PbPb at LHC
L dt (nb-
1)
RHIC
2x1026 8x1026L (cm-2s-1)
RHIC: 14 weeks production/yr, 4 experiments
LHC: 4 weeks production/yr, 2-3 experimentsDesign L by third year
LHC
8x1026
RHIC II: 14 weeks production/yr
RHIC II ?
8x1027
L dt (RHIC II) = 35 L dt (LHC)
eRHIC / EIC (?)
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Questions about RHIC II
• Is there compelling physics at RHIC II (with LHC)?
• How to harvest effectively this physics? – Evaluate experimental capabilities / detector complement at RHIC II?– Funding (upgrades, R&D, new detectors)?
• Finally, how to convince colleagues outside the field? – Long-term competition and NSAC Long Range Plan (2006)?
• Other physics / questions?– Identify them and best solutions……..(just starting)
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
A Start at Addressing Questions about RHIC II
Compelling physics at RHIC II!– Identify in detail properties of the QGP
(as a function of multiple variables)• Parton tomography of the QGP• Melting of the “Onium” States [J/, ’, Y(1s), Y(2s), Y(3s)]• Collective flow effects• Fluctuations (parity violation)?• Two-photon HBT to determine the temperature of the QGP• Others
– Establish the initial conditions at low x (forward rapidities)• Saturation / color glass condensate
– Determine structure and dynamics of the proton• Rare processes: sea polarization, parity-violating processes
– Investigate details of QCD – exotic hadrons, glueballs• 5-quarks, glueballs, others…..
– Exotic or new effects?– Others?
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
How to Harvest this Physics?• Utilize hard probes / large (pT, y) acceptance
– Jets
– High-pT PID particles
– -high-pT correlations
– e+e-,+ pairs for J/, Y(1s), Y(2s), Y(3s)– e, determination for W decays– Detailed low-x forward coverage (tracking, calorimetry)
• General Detector Requirements– ~4 EM + hadronic calorimetry (includes detailed forward coverage)– high resolution tracking (in large Bdl and forward)– PID to p ~ 20-30 GeV/c (flavor tagging)– high rate DAQ and specialized triggering
• Experimental Approach & Possible Solution– Utilize (to extent possible) existing High Energy Magnet/components
• e.g. SLD, CDF, D0, H1, …..– Build “smart”, fast, state-of-art detector components
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
d+Au RCP at forward rapidities
pT [GeV/c]
RC
P • Au-side RCP almost no variation with centrality
• d-side RCP interesting - central is most suppressed
L.Barnby, STAR QM’04
STAR Preliminary FTPC
Au-side
d-side
cen
tral
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
d
Au
Phenix Preliminary
Hadrons
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
dAu
Phenix Preliminary
Hadrons
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
dAu
Shadowing?Cronin effect &anti-shadowing?
Stopped Hadrons!
Phenix Preliminary
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Predictions from Theory for dAu and pAu
Hard Scattering: I. Vitev nucl-th/0302002 v2
Y=0
Y=3
Y= -3
CGC at y=0
Very high energy
As y grows
Color Glass Condensate
D. Kharzeev et al., PR D68:094013,2003
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Nuclear modifications in dAu at = 3.2!
RHI Physics at RHIC (II) in an LHC-era
Saturation at low x (10-3)?
RHIC in unique region!
ycm final state effects
forward initial state
HERA RHIC LHC eRHIC
BRAHMS, R. Debbe (QM-2004)
PRL 91 072305 (2003)
LHC ions saturated (ycm)?
LHC ycm
RHIC ycm
RHIC forward
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Measure QGP Properties & Shadowing/Saturation/CGC (low-x forward physics) with Hard Probes – some examples:
– Measure modification of FF’s as parton traverses QGP via
• jets, photons, high-pT identified particles
– Measure initial conditions (saturation) vs final state (parton E-loss) effects
• x-dependence – compare pA, AA, forward- vs mid-rapidities
– Determine initial energy of the parton scattering for accurate E-loss via
• Photon-tag on opposite side (rates are low)
– Measure flavor-dependence of jet quenching via
• -jet, -leading hadron, di-hadrons, di-jets (even lower rates)
• displaced vertices for D- and B-decays (reduced E-loss for heavy quarks)
– Measure deconfinement via melting of the Y(1s), Y(2s) and Y(3s) states
• e and identification
– Collective flow (effects on every observable, time evolution)
– Fluctuations (parity violation, always new ideas)?
– Two-photon HBT to determine photon spectrum & temperature of the QGP
Interesting RHI Physics at RHIC II
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Measure Polarization in Proton and Rare Processes with Hard
Probes:
– Heavy flavor production (polarized and unpolarized gluon distn’s)
– Jet physics (for polarization in proton)
– Electro-weak Physics (W+, W- decays for polarization of QCD sea)
– Physics beyond the Standard Model (parity-violating interactions)
• Understanding Details of Strong Interactions (QCD)
some examples in pp collisions (possibly AA):
– Measure “composite” particle spectrum (pentaquarks, glueballs?) in 1–3 GeV
mass range
• High statistics 2-, 3-, 4-particle correlations with PID in pT range up to 5
GeV/c and forward to large pseudo-rapidity
• Missing mass and energy measurements as well as quantum numbers
(very forward)
– Further search for the H di-baryon
Interesting Polarized and Unpolarized pp Physics at RHIC II
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Detailed Study of the QGP and Initial Conditions
FQGP (gQGP) = finitial (√s, A1+A2, b, x1, x2, Q2)
fQGP (pT,y , ,pT
jet,y jet ,jet,flavor jet, flow)
• Probes
– Jets
– High pT identified (light-, s-, c-, b-quark) particles
– photons
– -jet, - high-pT identified particle, particle-particle, di-jets
• Use Hard Probes over Multi-Parameter Space:
– Energy - √s
– Geometry - system A1+A2 , impact parameter b
– Rapidity (x-dependence) to forward angles
– Transverse momentum of jet / leading particle
– Particle type (flavor)
– Orientation relative to flow plane ( flow)
– Photon-tag on opposite side
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Detailed “Tomography” of the QGP
/parton
parton
flow plane
FQGP (gQGP) = finitial (√s, A1+A2, b, x1, x2, Q2)
fQGP (pT,y , ,pT
jet,y jet ,jet,flavor jet, flow)
Detailed QGP “Tomography”
parton
parton
parton parton
par
ton
parto
n
parton parton, parton parton
parton
parton
jet
leading particle
(light-, s-, c-, b-quark)
jet
jet
leading particle
(light-, s-, c-, b-quark)
leading particle
(light-, s-, c-, b-quark)
parton
parton
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Modification of Fragmentation Function
Induced Gluon Radiation• Softens fragmentation
in je
i j t
t
n e
: increases
z : decreases
chn
Gyulassy et al., nucl-th/0302077
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Gyulassy RHIC II Workshop (4/16/04) Talk
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Gyulassy RHIC II Workshop (4/16/04) Talk
Two main jet physics categories for new detector
• Global medium modification measurements based on rate, tracking hermiticity and complete calorimetry (add: Gamma-jet and forward jet measurements)
• Determine jet energy and particle distribution with and without medium modification
• Determine gluon vs. quark jet distributions and medium modifications
• Specific medium modifications measurements based on particle identification, rate, hermiticity and completeness of jet (add: Identified leading and associated particles, full jet measurments in terms of energy and pid).
• Heavy quark energy loss through R(AA) and rapidity distribution• Decouple effects of PDF and FF medium modifications based on
identified particle distributions inside the jet.• Determine energy loss mechanism from medium modification to
different flavor partons• Determine radiative vs. collisional energy loss as a function of jet
characteristics
R. Bellwied, RHIC II Workshop
• We might push the envelope on the ‘reference system’, i.e. our measurements in the pp system will replace many basic jet property measurements by adding particle identification and coverage to the original measurements.
– New insight in the relative importance of PDF and FF to the final state particle distribution.
– New insight into the origin of the spin of the nucleon– New insight into gluon vs. valence quark vs. sea quark PDF– New insight into the parton to hadron fragmentation functions based on better pid
measurements
• Bottomline: The goal is to characterize the features of in-medium QCD compared to in-vacuum QCD. Along the way we learn about the medium and we learn about fragmentation and hadronization. This program is complementary to the LHC main physics goals.
…and let’s not forget…
R. Bellwied, RHIC II Workshop
• Long range vs. short range gluon radiation
• Quark jet vs. gluon jet medium modification
• Impact of flavor dependence of parton distribution on medium modification
• Understanding leading particle asymmetries and their modifications
• Modifications to identified particle correlations in jet
• Different medium modifications to different particle fragmentation functions? Are heavy quarks different in medium than light quarks?
Fundamental questions of in-medium vs. vacuum QCD properties that can be answered with specific jet measurements
R. Bellwied, RHIC II Workshop
Question: do heavy quarks (charm, bottom) lose energy similar to light quarks ? Dead cone effect ?
Example: Heavy Quark Energy Loss
• Exclusive jet tagging:
– High- pT lepton (B→Dl) &
displaced vertex
– Hadronic decay (ex.D0 K-+) &
displaced vertex
• Ratio D/hadrons (or D/0)
enhanced and sensitive to
medium properties.
tpp
tAA
collAA dpdN
dpdN
NR
/
/1
R. Bellwied, RHIC II Workshop
Nuclear modification of heavy quark fragmentation function (e.g. nucl-th/0205064)
R. Bellwied, RHIC II Workshop
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Flavor-tagged Phenomena• Strange and charmed hadron/antihadron asymmetry
– Leading particle effect (e.g. E791, hep-ex/0009016)
• Intra-jet strange hadron production
– Difference in gluon and quark jets (e.g. OPAL, hep-ex/9805025)
• Fragmentation function parametrizations for heavy hadrons
– Flavor quenching, dead cone effects (e.g. hep-ph/0106202)
• Additional production mechanisms for s,c,b hadrons
– Recombination or gluon radiation (e.g. nucl-th/0306027)
• Transverse and longitudinal polarization
– Disappearance in AA (e.g. nucl-th/0110027)
General Jet Phenomena• Rapidity gaps between jets
– Difference between quark and gluon jets (e.g. hep-ph/9911240)
• Jet like contributions outside the jet cone (pp, pA, AA)
– ‘pedestal effect’, small vs. large angle gluon radiation
(e.g. Stewart, PRD42 (1990) 1385, hep-ph/0303121)
Measure Other Modifications in pp vs pA vs AA
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• PYTHIA prediction agrees well with the inclusive 0 cross section at 3-4
• Dominant sources of large xF production from:
• q + g q + g (22) + X
• q + g q + g + g (23) + X
g+g and
q+g q+g+g
q+g
Soft processes
PYTHIA: a guide to the physics (L. Bland, RHICII Workshop 4/17/04)Forward Inclusive Cross-Section: Subprocesses involved:
q
gg
q g
STAR FPD
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Relativistic Heavy Ions– Jets, high pT leading particles:
• Excellent p/p up to pT = 40 GeV/c (ycm)• Electromagnetic / hadronic calorimetry over ~4 phase space• Particle identification out to high pT (p ~ 20-30 GeV/c) • hadron (,K,p) and lepton (e/h, /h) separation central and forward
– Flavor dependence: • Precision vertex tracking (displaced vertices c/b-decays)
– Onium: • Large solid angle coverage for e and
High rate (40kHz) detectors, readout, DAQ, trigger capabilities.
Detector Requirements from RHI Physics
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Spin (polarized pp)– Heavy Quark Production (gluon polarization): e, detection
open beauty production as probe of gluon polarization
leading order diagram for heavy quark production in gg-fusion:
– QCD (especially jet physics, gluon polarization):
jet reconstruction (EM + hadron calorimetry)
single-photon detection (/πo separation), b/c-tagging
leading order diagrams for gluon-initiated jets:
– Electroweak Physics (QCD sea polarization via W):
W e, + X requires forward e and detection,
no away-side jet
e, triggers
large forward acceptance
– Physics beyond the Standard Model (parity violating processes):
e and detection, jet reconstruction, b/c-tagging, missing energy
Detector Requirements from Spin Physics
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Full acceptance in barrel and forward/backward region (0 < || < 3-4) – Tracking
– High-rate capabilites (pixel, silicon and GEM-type detectors)– Precision inner vertex detector system - secondary vertex
reconstruction, momentum resolution– Large Bdl, B ~ 1.5 T over 2 m.
– Particle Identification– , K, p to ~20-30 GeV/c– precision inner vertex detector system - secondary vertex
reconstruction, momentum resolution– Electromagnetic and hadronic energy
– transverse and longitudinal tower segmentation (for jet reconstruction and electron/hadron separation).
• Specialized calorimeter / tracking beyond ||~4 at small x for Emissing
• system in barrel and forward/backward region for heavy flavors• Large Bdl, B ~ 1.5 T over 2 m.• Precise relative luminosity measurement at high-rates • Local polarimeter & absolute luminosity measurement• High rate DAQ, triggering for rare processes, secondary-vertex trigger
Detector Specification
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Re-cycle existing equipment– Utilize detector components from other collider experiments that are
decommissioned, or will be in the near future, e.g. SLD, CDF, D0, CLEO– Should be possible to identify and procure existing high field magnet and a
large amount of electromagnetic and/or hadronic calorimetry.
• Build new fast detectors, electronics, DAQ, triggers– New technologies, tracking, PID, electronics, DAQ, triggering
Our Approach
CDF D0 CLEO ALEPH SLD
Magnet 1.4T,SC 2.0T,SC 1.5T,SC 1.5T,SC 1.5T-upg-SC
R in m 1.5 0.55 1.45 2.48 2.8
L in m 4.8 2.7 3.5 7.0 7.0
Bdl 2.1 1.0 2.0 3.75 4.2
HCal Fe/Sc, 0.78/√E
LiquidAr, 0.62/√E
No FET str tube 0.65/√E
FET str tube 0.85/√E
EMC Pb/Sc, 0.13/√E
LiquidAr, 0.15/√E
CsI crys, 0.03/√E
Pb/W, 0.18/√E
LiquidAr, 0.15/√E
detector yes yes yes yes yes
Decommis-sioned ?
2009 2007-09 2007 yes yes
Y
X R = 2.8 m
SLD magnet, hadronic cal. + -chambers || < 3 (depth = 15 x (5 + 5) cm, r = 0.3 cm, z = 3 cm)
π/K/p (1-30 GeV/c) PID: Gas RICH (C5F12) with Spherical Mirror Read-out: CsI pads sensitive to UV and MIP
AeroGel Cherenkov Detectors with two values of N
SC Magnet Coil, 1.5 T
EMC: Crystals + Fe(Pb)/Sc (accordion type, projective) or LAr 6x6 mrad towers
Additional Tracking: Si Vertex, 4 Pad Detectors in Barrel and End Caps (-pattern) Si + Pad Detectors Forward
dZ = 3.0 m
3-6 layers Si-strip detectors or mini-TPC
ToF RPC’s
R =
2.8
m
A Proof of Principle
Comprehensive RHIC II Detector
Detector Coverage
1. 2. 3. 4. 5. 6. 7. 8. 9. 10 12. 14. 16 18.
p (GeV/c)
A1+ToF A1+A2+RICHRICH
ToF
PID (, K, p)
Calorimetry & μ-detector: -3 < η < +3
Tracking: -3 < η < 4.5
PID: = -1.2 < η < 3
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Tracking Detectors under ConsiderationTracking Detectors in Barrel Simulation Detector R position half-length Sigma-r Sigma-Z Thickness
(cm) (cm) (cm) (cm) (cm)Vertex detector[1]1. APS 1 2.8 9.6 0.001 0.001 0.02 or 2 4.3 12. Si Pixel 3 6.5 21. 4 10.5 27.
Main tracker 2a. Si strip 1 19. 39. 0.003 0.03 0.03 2-sided 2 24.5 42. 3. 31. 45. 4. 38.5 51. 5. 46. 57. 6. 56. 60. or
2b. miniTPC 22.5 – 60. 55. 0.012 0.035 0.2 Mylar + Gas (35 pad rows with 0.2x0.8 pad size)
High pT tracker
3. Micro-pattern pad detector 1. 70. 76. 0.17 0.17 0.3 G10 + 2. 115. 110. 0.01 0.9 1.Gas + 3. 135. 130. 0.01 1.2 0.05 Mylar 4. 170. 165. 0.01 1.4
[1] Only two vertex detector layers were used in the track reconstruction of this simulation. These were Si pixels of 20100 m2 size at 6.5 and 10.5 cm radii.
What is needed to extend forward What is needed to extend forward measurements significantlymeasurements significantly
• Extend pt reach to ~6 GeV/c for inclusive spectra.
• Kinematic limit restricts such measurements to ~2-3.5
• Momenta and PID determination in range of 20-60 GeV/c
Videbaek – Yale RHIC II Workshop 4/16/04
GEANT simulation was started for the “SLD-like” set upAll materials and detector resolution parameters:
“reasonable and conservative”
N. Smirnov, RHIC II Physics and Perspectives for a New Comprehensive Detector Workshop
Solenoid with Bz = 1.5T; {toroidal field, lamp-shape field, …}
6 planes Si tracker
CalorimeterR
Z
Y
X+/-3.5 m
1.6 m
μ-detector
η = 1.
η = 2.
η = 3.45
η = 4.2
R = 3. mBz = 1.5 T
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Momentum Resolution
dPt/Pt, %
dPt/Pt, %dPt/Pt, %
Pt, GeV/c
Pt, GeV/c
dPt/Pt, %
Pt, GeV/c
IηI < 0.8 0.8<IηI < 1.6
IηI > 2.2
IηI
Pt = 10. GeV/c
Pt = 2. GeV/c
5. 10. 20. 30. 5. 10. 20. 30.
2. 4. 8. 12.
10 10
10
1 1
10
40
40
1 2 3
Pad detectors only
all tracking detectors
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Detector parameters to consider:– Particle identification (PID) reach in momentum– Pseudo-rapidity coverage– Detector resolutions: momentum, energy, two-track– Data acquisition (DAQ) rate
• A new comprehensive detector would be superior to:– Upgraded STAR in terms of resolution, PID, coverage (inc.
calorimetry), rate– Upgraded PHENIX in terms of PID, coverage (inc. calorimetry)– ALICE in terms of PID, coverage, resolution, statistics/operation
(pp, pA?, AA)– CMS in terms of PID, statistics/operation (pp, pA?, AA)
Detector Parameter Considerations for Detector Comparisons
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Fast tracking detectors complement fast PID, calorimetry– 40x improvement in DAQ rate compared to STAR
High resolution EM calorimeter and chambers– allows resolution of all Y states
Near 4 coverage in tracking, PID, calorimetry– 20x improvement in heavy quark probes compared to PHENIX
(> 20,000 Y per RHIC year, and still > 3000 Y(3s))
PID out to 20-30 GeV/c over ~4 with high two-track resolution tracking– Measure actual jet physics rather than leading particle physics
• Particle identify all particles in jet
• Measure intra-jet correlations between identified hadrons in jet
– Direct heavy flavor tagging of jets via leading particle reconstruction
-jet measurements with away-side spectrum out to 20 GeV/c
(20 weeks at 40Lo)
– pT = 10 GeV/c 2.6 M events - pT = 15 GeV/c 260 K events
– pT = 20 GeV/c 30 K events
Various Aspects of Detector Extend the Physics Reach
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Quarkonium Measurements at RHIC• AA
– Goal: suppression as a signature of deconfinement in a QGP– Thermometer for early stages:
Tdis(’) < Tdis((3S)) < Tdis(J/) Tdis((2S)) < Tdis((1S))
• pp– Interesting in its own right
• no nuclear effects (production pure)• close s gap (fixed target CDF,D0)
– baseline for pA, AA– Spin: G via J/
• pA– necessary to understand nuclear effects
• xF, x1, x2 dependence
– Rates for rare processes increases by A compared to pp
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Quarkonium Measurements at RHIC
• Decay modes: 1S, 2S), (1S, 2S) ℓ ℓ
cJ/b
• – clean trigger– experiments have usually higher statistics than ee
– not the best when low pT is important
• ee
– trigger hard for J/ (no problem for )– larger background than
Requirements for 3rd Generation Detector
High Rate
Large acceptance rate + xF coverage
Pythia 6.2 Pythia 6.2
Requirements for 3rd Generation Detector
J/ measurements require:highly granular E.M Calorimeter at least at mid-
rapidityprobably only feasible in pp, pA, peripheral AA
need simulations here large acceptance
Reduce hadronic background high e/h possible with good calorimetry and PID up to
10-20 GeV/c situation better for muons anyhow
Good measure of reaction planeeasy with ZDC+SMD
T. Ullrich, RHIC II Workshop 4/16/04
Rates at RHIC-II
Assume here: large acceptance (||<3) one channel only (e+eor ) RHIC-II:
L = 5·1032 cm-2 s-1 (pp) L = 7-9·1027 cm-2 s-1 = 7-9 mb-1 s-1 (AuAu) hadr. min bias: 7200 mb 8 mb-1 s-1 = 58 kHz 30 weeks, 50% efficiency Ldt = 80 nb-1
100% reconstruction efficiency
AA = pp (AB)
T. Ullrich, RHIC II Workshop 4/16/04
Rates at RHIC-II Au+Au min bias rates
R(J/) = 27 Hz R(’) = 1 Hz R((1S)) = 0.01701 Hz R((2S)) = 0.00297 Hz R((3S)) = 0.00324 Hz
Au+Au, 30 weeks50% efficiency 2.7·108 J/ 1·107 ’ 170100 (1S) 29700 (2S) 32400 (3S)
pp lose factor (AB) gain Lpp/LAA ~ 60,000
T. Ullrich, RHIC II Workshop 4/16/04
e+e-(1S)
(2S)
full scale simulation / reconstruction
(3S)
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Need Open Charm Measurement
SPSs = 17 GeV RHIC
s = 200 GeV
At RHIC open charm production provides reference and is perhaps the only way to understand charmonium suppression (same gluon conditions in the initial stage)
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Quarkonia Summary In terms of quarkonia physics RHIC-II is not too far behind LHC
(LHC)/(RHIC) = 9 (GRV-HO) – 25 (MRS-D1) RHIC-II: 5 higher L RHIC: > 5 times longer running
T. Ullrich, Yale Workshop 4/2004
Measuring “just” J/ is not enough to extract a physically meaningful result
AA, pp, pA as function of pT, xF, centrality, reaction plane
A 3rd generation detector and RHIC-II luminosity provide a world class measurement in pp, pA, AA
Sufficient statistics to allow the study of production vs. pT, xF, centrality, reaction plane
Quarkonia in polarized pp might open a whole new opportunity unique to RHIC (I know too little about it for this talk)
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Forward Physics at RHIC-II
in p+p (transverse & longitudinal) and p(d)+nucleus
• ‘hard scattering’ particle correlations spanning large rapidity difference
o flavor tagging of partonic scattering
o longitudinal/transverse spin effects, selected on Bjorken x values of colliding partons
o probe rapidity dependence of saturation scale
• Large rapidity Drell-Yan (electroweak probes)
o quantify Sivers function (parton orbital angular momentum in proton)
o probe gluon saturation
from Les Bland Talk at RHIC II Workshop 4/16/04
p+p (200 GeV) X + W+/- e(μ)+/- + ν
A B
A
A
B
B
Pt, GeV/c
Rapidity
dPt/Pt
dPt/Pt
{e+}
{μ+}
N. Smirnov, RHIC II Physics and Perspectives for a New Comprehensive Detector Workshop
40
20
20
10
0 1 1 2
Sigma of dPt/Pt ~3.% ~6.% in a case p+p (500 GeV)
PYTHIA event generator
Case A: |η| < 1.2Case B: |η| = 1.2 - 2.4
– HBT possibilityThere is space to install a few miniTPCs ( 15 pad rows, 0.2x0.8 cm² pad size, 45 cm maximum drift distance) with a ~1. X0 photon convertor in a front (removable).
A: GEANT & TPC response & reconstruction. B: & Eloss, scattering C: & all EM interactions
Y
X
A B C
~0.3 deg ~0.5 deg
photon angle resolution dS/R
N. Smirnov, RHIC II Physics and Perspectives for a New Comprehensive Detector Workshop
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
What we still need to know
Is the produced matter a thermalized Quark-Gluon Plasma? If yes, what are its properties ?
Confirm that the observed high pT suppression is indeed due to the parton radiative energy loss
Study the dependence on the quark mass; induced QCD radiation is suppressed for heavy quarks (“dead cone” effect in the medium) => smaller quenching for the
charm/beauty jets; different jet shapes
Kharzeev, Yale Workshop 4/2004
Are effects observed at forward rapidity due to parton saturation in the CGC?
Back-to-back correlations for jets separated by several units of rapidity are very sensitive to the evolution effects (A.H.Mueller,H.Navelet, ’87) & to the presence of CGC (DK, E.Levin,L.McLerran, hep-ph/0403271)
Open charm, dileptons, photons (DK, K.Tuchin, hep-ph/0310..) in the forward region
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
What else is interesting at RHIC II
Diffractive production, especially double diffractive production at central rapidity very intriguing effects observed at CERN, (WA102 ‘97, F. Close, A. Kirk, hep-ph/9701222) possibly related to QCD anomalies: (J. Ellis, DK, hep-ph/9811222) (E. Shuryak and I. Zahed, hep-ph/0302231)
use A and Z dependence of the production cross sections to discriminate between (mostly) glueball and quark states!
Kharzeev, Yale Workshop 4/2004
Spin physics: access the sea polarization by looking at the target fragmentation region
difficult in fixed target expts, but very interesting effects (e.g., strong L polarization in n DIS) have been observed (WA59, …)
and related to the sea quark polarization: (J. Ellis, DK, A. Kotzinian, hep-ph/9506280; … )
these studies can give information on the spin correlations of partons in the nucleon
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
M. Gyulassy (nucl-th/0403032)
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
M. Gyulassy (nucl-th/0403032)
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Gyulassy RHIC II Workshop (4/16/04) Talk
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
Gyulassy RHIC II Workshop (4/16/04) Talk
Heavy Ion Tea, LBNL, Berkeley CA, 4/27/04Comprehensive RHIC II Detector
• Unique physics at RHIC II complementary with LHC– Detailed QGP tomography
– Fragmentation in-medium and in vacuum for light and heavy quarks, gluons
– Onium suppression
– Saturation vs. CGC
– Rare processes in spin physics
– Other? - must still develop this case!
• Comprehensive new detector system can harvest this physics– Proof of principle (full x, and pT range for all flavors)
– Maximize physics output from RHIC II – must still develop this case!
• Detailed simulations to optimize detector configuration– continuing!
• Forming exploratory working group!• Interest in community (to be developed!)
– Next generation of RHI physics in U.S.
– More theoretical input / guidance
– Experimental interest?
– Comments
Summary
presented at RHIC Planning Meetingpresented at RHIC Planning MeetingBNL on 4 Dec 2003BNL on 4 Dec 2003
Comprehensive RHIC II DetectorComprehensive RHIC II Detector
Ideas for a Ideas for a Comprehensive New DetectorComprehensive New Detector for for In-Depth Study of the In-Depth Study of the QGPQGP, , Initial ConditionsInitial Conditions
and and Spin PhysicsSpin Physics at RHIC II at RHIC II
R. Bellwied, J.W. Harris, N. Smirnov, R. Bellwied, J.W. Harris, N. Smirnov, P. Steinberg, B. Surrow, and T. UllrichP. Steinberg, B. Surrow, and T. Ullrich
Statement of Interest document and Yale Workshop (April 16-17, 2004)at
http://star.physics.yale.edu/users/harris/