Capabilities of the R2D
detector
Matt Lamont, Yale University
Relevant RHIC-I results
Hydrodynamics:
Strong collectivity in a liquid like (not
plasma) phase which requires a partonic EoS
Jet Quenching:
The ‘quenching’ of high pT particles due to
radiative partonic energy loss.
Energy loss 15 times higher (several
GeV/fm3 ) than in cold nuclear matter
(compare RHIC AA to HERMES eA)
Constituent quark scaling:
recombination provides a description ~1.5 - 5
GeV/c for identified particle properties
v2 and jet quenching might probe d.o.f above Tc !
Matthew.Lamont@yale.edu : RHIC II Workshop
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Contributions to particle production
in RHI collisions
SPS, RHIC-I
Soft
0
LHC, RHIC-II
RHIC-II: pT to 30 GeV/c
Parton
Medium60 GeV
Max.
jet
energy:
recombination
modified
Fragmentation
and
fragmentation
(jet quenching)
coalescence
~ 2 GeV/c
~ 6 GeV/c
~ 30 GeV/c ?
Matthew.Lamont@yale.edu : RHIC II Workshop
pT
3
Are p+p particle spectra at
RHIC-II pT limited ?
pq,g > 10 GeV/c
pq,g > 10 GeV/c
all h
|h| < 0.5
106 particles in AA
5 Gev higher in momentum
 factor 10x smaller yield
100K L with pT >20GeV
Multiply pp events by factor of ~ 8 x 1015 for AuAu events in 30 nb-1 RHIC-II year
Matthew.Lamont@yale.edu : RHIC II Workshop
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R2D Concepts
• What is missing in current RHIC detectors ?
– Large, continuous coverage in h,  and pT
• Onium, -jet, RAA (hpT,), v2 (hpT)
– PID out to high pT
• Identified v2, identified jets, identified 2-particle
correlations
– Hadronic calorimetry
• Isolation cuts, missing energy, unbiased jet triggering
Matthew.Lamont@yale.edu : RHIC II Workshop
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Requirements for an Ideal Detector
• High rate detectors, DAQ
– Required for high luminosity A+A, p+A and p+p collisions at RHIC II
• Uniform high magnetic field over “large volume”
– Good quality tracking/momentum measurements
• Precision Vertex tracking
• 4 EM and Hadronic Calorimeters
– Missing energy measurements and  identification
• e/h discrimination
– At low pT as well as at high pT
 /K/p identification
– Momentum up to ~ 25 GeV/c
• Forward capabilities
– High-rapidity measurement/identification possibility
Matthew.Lamont@yale.edu : RHIC II Workshop
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EOI for a comprehensive New
Detector for RHIC II
P. Steinberg, T. Ullrich (Brookhaven National Laboratory)
M. Calderon (Indiana University)
J. Rak (Iowa State University)
C. Markert, S. Margetis (Kent State University)
M.A. Lisa, D. Magestro (Ohio State University)
R. Lacey (State University of New York, Stony Brook)
G. Paic (UNAM Mexico)
T. Nayak (VECC Calcutta)
R. Bellwied, C. Pruneau, A. Rose, S. Voloshin (Wayne State University)
and
H. Caines, A. Chikanian, E. Finch, J.W. Harris, M.A.C. Lamont,
J. Sandweiss, N. Smirnov (Yale University)
Submitted : Aug 04, ArXiv : nucl-ex/0503002
Matthew.Lamont@yale.edu : RHIC II Workshop
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L-R2D - SLD Magnet
2.8m
6m
Matthew.Lamont@yale.edu : RHIC II Workshop
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S-R2D - “CDF” Magnet
CDF, CLEO and BABAR have same size magnets
SC Coil; R = 1.5 m; Bz = 1.5 T
EMC, CsI crystal, ~24 X0
Si Strip Detectors
AeroGel2 Ch. D.
AeroGel1 Ch. D.
HC and Muon Detectors
Rcoil = 150 cm
Gas RICH Detectors
GEM Tracking D.
Si Vertex D.
Matthew.Lamont@yale.edu : RHIC II Workshop
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Differences between L-R2D
and S-R2D
• Magnetic field strength
– 1.3T  1.5T - not much difference (~2.5x STAR)
• PID capabilities
– Dependent on RICH detectors, not layout
• Size/Cost
– SLD layout is larger and more costly in terms of
infrastructure (need changes to 12 o’clock, CDF
layout fits inside a current hall).
• No difference in physics observables for
either layout.
Matthew.Lamont@yale.edu : RHIC II Workshop
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Need high pT PID and large
acceptance !
2
10 GeV
PHENIX

STAR, 4 GeV
R2D, 25 GeV
4 GeV
0
-4
-3
-2
-1
0
1
Matthew.Lamont@yale.edu : RHIC II Workshop
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3
4
h
11
Large acceptance for all
detector components
• High momentum PID
– RICH + Aerogel
• Calorimeters
– EMCAL + HCAL
• Central Tracker
• Vertex Tracker
• All components cover |h| < 3.5 PLUS
dedicated forward tracker to |h| < 4.8
Matthew.Lamont@yale.edu : RHIC II Workshop
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Acceptance in h and pT
Essential for jets, high pT correlations, quarkonium, spin programs
•
h distributions in pp (+jet)
Preliminary STAR results on number
correlations for pT < 2 GeV/c
• Broadening in h and  pp
pp
 AA
AA
Octupole Twist
nucl-th/0505004
parton fragmentation modified in dense
color medium:
Dh elongation even on near side
can measure 40 GeV jets: 180k in 30 nb-1
Matthew.Lamont@yale.edu : RHIC II Workshop
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L-R2D
Detector
Coverage
PID
Calorimeter and μ-detector: η = +/- 3.4
Tracking: η = (-3.5 – +4.5)
PID: h = +/- 1.2 (2.8)
RICH : C5F12 - n = 1.00175
PID (, K, p)
dE/dx, ToF
A1+ToF
1.
2.
3.
A1+A2+RICH
4.
5.
6.
7.
RICH
8.
9.
10
12.
14.
Matthew.Lamont@yale.edu : RHIC II Workshop
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18.
p (GeV/c)
14
Momentum reconstruction
{ |η| = (0. - 2.) }
dpT/pT, %
20
dpT/pT, %
η = 3. – 4.
10
|η| = 2.5 – 3.
8.
Pad Detectors only
All tracking
4.
*
|η| = 2. – 2.5
|η| = (0. - 2.)
4
10
5.
pT, GeV/c
Matthew.Lamont@yale.edu : RHIC II Workshop
15.
30.
pT, GeV/c
15
J/,  e+e- (μ+μ-), |h|<2
One particle / event; no background
J/Ψ  e+eΥ  e+ew/ upgrade
(1S)
STAR:
Dm = 340  170 MeV
(1S)
(2S) (3S)
(2S)
3.
Dm ~ 35 MeV
4. GeV
9.
PHENIX:
Dm = 170  60 MeV
10. GeV
Dm ~ 65 MeV
For J/Ψ (Y)  μ+μ- resolutions are the same.
Matthew.Lamont@yale.edu : RHIC II Workshop
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Quarkonium Rates in R2D
Au+Au minbias, 30 nb-1 : (plepton > 2 GeV/c for J/, 4 GeV/c for )
100,000,000
10,000,000
1,000,000
100,000
10,000
1,000
Matthew.Lamont@yale.edu : RHIC II Workshop
Y'
'
?
Y'
Xc
Ps
i'
10
Xc
?
Y
100
J/
Ps
i
New Detector
PHENIX
17
High pT Identified particles & jets in
R2D
Matthew.Lamont@yale.edu : RHIC II Workshop
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Summary : Comparative
Physics Reach
PHENIX-II
STAR-II
ALICE
R2D
De-confinement and low x physics
a.) Onium physics
’
J/cc
Y(1s)
Y(2s)
Y(3s)
Fragmentation and hadronization
a.) Di-hadron jets
10 GeV
20 GeV
30 GeV
40 GeV
b.) Rapidity gap measurements and forward physics
Dh > 1
>2
>3
>4
>5
>6
b.) Gamma-jet with identified hadrons (h > 5 GeV/c)
5 GeV 
10 GeV 15 GeV
20 GeV
c.) Degrees of freedom above Tc (w. PID)
v2 > 4 GeV/c::R(AA) |h|=1::v2 > 10 GeV/c::R(AA) |h|=3
c.) Identified high pT di-hadron correlations
pp > 3 GeV/c > 5 GeV/c > 10 GeV/c LL> 5 GeV/c
Matthew.Lamont@yale.edu : RHIC II Workshop
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Backup Slides
Matthew.Lamont@yale.edu : RHIC II Workshop
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How PID is done in R2D
Muons:
- MIP track reconstructed in
HC, “catcher” & Muon Detector;
- matching with track inside of Magnet
e/h:
- high Pt; EMC (E/p), HC, all Ch. Detectors
- low Pt; dE/dX, ToF, Ch. Detectors
π/K/p:
- dE/dX, ToF, AeroGel and Gas Ch. ,
& gas RICH Detectors
Matthew.Lamont@yale.edu : RHIC II Workshop
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dpT/pT and PID possible
performances ( barrel part)
2.
AG – AeroGel Ch. D.
GCh – Gas Ch. D.
0.5
Plus: dE/dX, EMC, HC, Muon D.
π
AG1 +AG2 + GCh1
+GCh2
π
AG1
K
+AG2
+GCh1
+GCh2
K
AG1
p
2
4
6
8
+AG2
10
+GCh1
12
14
Matthew.Lamont@yale.edu : RHIC II Workshop
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18
p
20 GeV
22
Matthew.Lamont@yale.edu : RHIC II Workshop
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Matthew.Lamont@yale.edu : RHIC II Workshop
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Matthew.Lamont@yale.edu : RHIC II Workshop
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Matthew.Lamont@yale.edu : RHIC II Workshop
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