EIC Detector Overview
Tanja Horn
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Electron-Ion Collider Advisory Committee, Jefferson Laboratory, Newport News, VA
10 April 2011
1
Science of an EIC: Explore and Understand Science of an EIC: Explore and Understand QCDQCD
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011 2
• Map the spin and spatial quark-gluon structure of nucleons(̶ Image the 3D spatial distributions of gluons and sea quarks through exclusive J/Ψ, γ (DVCS) and
meson production
(̶ Measure ΔG, and the polarization of the sea quarks through SIDIS, g1, and open charm production
(̶ Establish the orbital motion of quarks and gluons through transverse momentum dependent observables in SIDIS and jet production
• Discover collective effects of gluons in nuclei(̶ Explore the nuclear gluon density and coherence in shadowing through
e + A → e‘ + X and e + A → e‘ + cc + X
(̶ Discover novel signatures of dynamics of strong color fields in nuclei at high energies in e + A → e’ + X(A) and e + A → e’ + hadrons + X
(̶ Measure gluon/quark radii of nuclei through coherent scattering γ* + A → J/Ψ + A
• Understand the emergence of hadronic matter from quarks and gluons− Explore the interaction of color charges with matter (energy loss, flavor dependence, color
transparency) through hadronization in nuclei in e + A → e' + hadrons + X
− Understand the conversion of quarks and gluons to hadrons through fragmentation of correlated quarks and gluons and breakup in e + p → e' + hadron + hadron + X
[INT 2010]
C. Weiss
s
• For large or small y, uncertainties in the kinematic variables become large
Range in yQ2 ~ xys
Range in s
Range of kinematics
• Detecting only the electron ymax
/ ymin
~ 10
• Also detecting all hadrons ymax
/ ymin
~ 100
– Requires hermetic detector (no holes)
• Accelerator considerations limit smin
– Depends on smax
(dynamic range)
• At fixed s, changing the ratio Ee / E
ion can for
some reactions improve resolution, particle identification (PID), and acceptance
C. WeissC. Weiss
valence quarks/gluons
non-pert. sea quarks/gluons
radiative gluons/sea
[Weiss 09]
s
To cover the physics we need…To cover the physics we need…
3Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Vacuum fluct.
pQCD radiation
1. 1. To a large extent driven by exclusive physicsTo a large extent driven by exclusive physics
22. But not only .... But not only ...
• Hermeticity (also for hadronic reconstruction methods in DIS)• Particle identification (also SIDIS)• Momentum resolution (kinematic fitting to ensure exclusivity)• Forward detection of recoil baryons• Muon detection (J/Ψ)• Photon detection (DVCS)
• Very forward detection (spectator tagging, diffractive, coherent nuclear, etc.)
• Vertex resolution (charm)• Hadronic calorimetry (jet reconstruction)
Detector RequirementsDetector Requirements
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011 4
Where do particles go - generalWhere do particles go - generalp or A e
Many processes of interest in e-p:
Token example: 1H(e,e’π+)n
5Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
In general, e-p and even more e-A colliders have a large fraction of their science related to the detection of what happens to the ion beams. The struck quark remnants can be guided to go to the central detector region with Q2 cuts, but the spectator quark or struck nucleus remnants will go in the forward (ion) direction.
[Ent 10+]
Even more processes in e-A:
1) “DIS” (electron-quark scattering) e + p e’ + X
2) “Semi-Inclusive DIS (SIDIS)” e + p e’ + meson + X
3) “Deep Exclusive Scattering (DES)” e + p e’ + photon/meson + baryon
4) Diffractive Scattering e + p e’ + p + X
5) Target Fragmentation e + p e’ + many mesons + baryons
1) “DIS” e + A e’ + X
2) “SIDIS” e + A e’ + meson + X
3) “Coherent DES” e + A e’ + photon/meson + nucleus
4) Diffractive Scattering e + A e’ + A + X
5) Target Fragmentation e + A e’ + many mesons + baryons
6) Evaporation processes e + A e’ + A’ + neutrons
6
diffractive DIS
Diffractive and Deep Inelastic Diffractive and Deep Inelastic ScatteringScattering
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
10°
5°
Mom
entu
m (
GeV
/c)
Mom
entu
m (
GeV
/c)
• High-momentum mesons at small angles
4 on 250 GeV
4 on 50 GeV
Angle (deg) Angle (deg)
40 206080100120140160180
Angle (deg)
40 206080100120140160180
[W. Foreman 09]
40 206080100120140160180
40 206080100120140160180
Angle (deg)
10
1
10
1
No cuts
Small angle detection important
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011 7
[Horn 08+]recoil baryonsscattered electronsmesons
4 on
250
Ge
V4
on 3
0 G
eV
PID challenging
0.2° - 0.45°
0.2° - 2.5°
ep → e'π+n
Exclusive light meson kinematicsExclusive light meson kinematicsQ2>10 GeV2
Mom
entu
m (
GeV
/c)
Mom
entu
m (
GeV
/c)
Mom
entu
m (
GeV
/c)
Mom
entu
m (
GeV
/c)
t (G
eV2)
t (G
eV2)
Lab Scattering Angle (deg)
Lab Scattering Angle (deg)
Lab Scattering Angle (deg)
Lab Scattering Angle (deg)
Lab Scattering Angle (deg)
very high momenta
electrons in central barrel, but p different
t/t ~ t/Ep
Θ~√t/Ep
Lab Scattering Angle (deg)
8
EM
Cal
orim
eter
Had
ron
Cal
orim
eter
Muo
n D
etec
tor
EM
Cal
orim
eter
Solenoid yoke + Hadronic Calorimeter
Solenoid yoke + Muon Detector
HT
CC
RIC
H
Cerenkov
Tracking
5 m solenoid
• JLab layout has conical rather than cylindrical forward / backward trackers (with line-of-sight from IP)
• JLab detector does not have the forward RICH inside the solenoid magnet
• JLab detector allocates space for Cerenkov (LTCC) in central barrel for high-momentum PID
• JLab interaction region has a larger ion beam crossing angle 50-60 mrad vs 10 mrad
Minor differencesMinor differences
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
JLabJLab and and BNLBNL central detector layouts central detector layouts similarsimilar
JLab BNL
DIRC Cerenkov
EM
-C
alor
imet
er
HT
CC
Hadronic Calorimeter
Tracking RIC
H
EM
-C
alor
imet
er
5 m solenoid
e- Beamp/A Beam
Central DetectorCentral Detector
9Tanja Horn, Introduction to EIC/detector concept, Exclusive Reactions Workshop
2010
• 3-4 T solenoid with about 4 m diameter
• TOF for low momenta
• π/K separation
• p/K: DIRC up to 7 GeV
• e/π: C4F
8O LTCC up to 3 GeV
Solenoid Yoke, Hadron Calorimeter, MuonsSolenoid Yoke, Hadron Calorimeter, Muons
Particle IdentificationParticle Identification
• Low-mass vertex tracker
• GEM-based central tracker
• Conical endcap trackers
Solenoid yoke + Hadronic Calorimeter
Solenoid yoke + Muon Detector
LTCC / RICH
Tracking
TrackingTracking
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011 9
• precise vertex reconstruction (< 10 μm) separate Beauty and Charmed Meson
BNL Detector R&D projects
JLAB Detector R&D projects
• low radiation length extremely critical low lepton energies
10 on 50 (s=2000 GeV2)
Mom
entu
m (
Ge
V/c
)
Lab Scattering angle (deg) Lab Scattering angle (deg)
BaBar DIRC
“Super-DIRC”
4 on 30 (s=480 GeV2)
DIRC+gas Cerenkov or (dual radiator barrel RICH)
Detector EndcapsDetector Endcaps
10Tanja Horn, Introduction to EIC/detector
concept, Exclusive Reactions Workshop 2010
• Bore angle: ~45° (line-of-sight from IP)
• High-Threshold Cerenkov (e/π)
• Time-of-Flight Detectors
8̶ Hadrons, event reconstruction, trigger
• Electromagnetic Calorimeter (e/π)
• Bore angle: 30-40° (line-of-sight from IP)
• Ring-Imaging Cerenkov (RICH)
• Time-of-Flight Detectors (event recon., trigger)
• Electromagnetic Calorimeter
8̶ Pre-shower for γ/π° -> γγ (very small opening angle at high p)
• Hadronic Calorimeter (jets)
• Muon detector (J/Ψ production at low Q2)
Space constraintsSpace constraints
Electron side (left)Electron side (left)
Ion side (right)Ion side (right)
• Electron side has a lot of space
• Ion side limited by distance to FFQ quads (7 m @ MEIC, eRHIC similar)
EM
Cal
orim
eter
Had
ron
Cal
orim
eter
Muo
n D
etec
tor
EM
Cal
orim
eter
TOF
HT
CC
RIC
HTracking
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
10
BNL Detector R&D projects
JLAB Detector R&D projects
Δp/p ~ σp / BR2175°
R1
R2
Crossing angle
• A 2 Tm dipole covering 3-5° eliminates divergence at small angles
• Only solenoid field B (not R) matters at very forward rapidities
• A 3° beam crossing angle moves the region of poor resolution away from the ion beam center line.
– 2D problem!
• Tracker (not magnet!) radius R is important at central rapidities
– Conical trackers improve resolution at endcap corners by (R
2/R
1)2 ~ 4 (not shown)
• position resolution σ~ 100 microns
– CLAS DCs designed for 150 microns
particle momentum = 5 GeV/c 4 T ideal solenoid field
cylindrical tracker with 1.25 m radius (R1)
Goal: dp/p ~ 1% @ 10 GeV/cGoal: dp/p ~ 1% @ 10 GeV/c
11Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Resolution dp/p in solenoidResolution dp/p in solenoid
Forward Detection – 2T-m dipoleForward Detection – 2T-m dipole
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
12
Forward / BackwardForward / Backward
Spectrometers:Spectrometers:
2m2m 4m4m
Dipoles needed to have good forward momentum resolution and acceptance
Δp/p ~ σp / BR2175°
R1
R2
Crossing angle
• A 2 Tm dipole covering 3-5° eliminates divergence at small angles
• Only solenoid field B (not R) matters at very forward rapidities
• A 3° beam crossing angle moves the region of poor resolution away from the ion beam center line.
– 2D problem!
• Tracker (not magnet!) radius R is important at central rapidities
– Conical trackers improve resolution at endcap corners by (R
2/R
1)2 ~ 4 (not shown)
• position resolution σ~ 100 microns
– CLAS DCs designed for 150 microns
particle momentum = 5 GeV/c 4 T ideal solenoid field
cylindrical tracker with 1.25 m radius (R1)
Goal: dp/p ~ 1% @ 10 GeV/cGoal: dp/p ~ 1% @ 10 GeV/c
13Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Resolution dp/p in solenoidResolution dp/p in solenoid
[Horn, Ent 08+]
Nuclear Science: Map t between tmin and 1 (2?) GeV Must cover between 1 and 5 degrees
Should cover between 0.5 and 5 degrees
Like to cover between 0.2 and 7 degrees
= 5 = 1.3
Ep = 12 GeV Ep = 30 GeV Ep = 60 GeV
t ~ Ep22 Angle recoil baryons = t½/Ep
t resolution ~ ~ 1 mr
14Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Challenge at small angles – recoil Challenge at small angles – recoil baryonsbaryons
[Horn 08+]
t (G
eV2)
Lab Scattering angle (deg)
t (G
eV2)
Lab Scattering angle (deg)
t (G
eV2 )
Lab Scattering angle (deg)
IP
ultra forwardhadron detection
dipole
dipole
low-Q2
electron detectionlarge apertureelectron quads
small diameterelectron quads
ion quads
small anglehadron detection
dipole
central detector with endcaps
EM
Cal
orim
eter
Had
ron
Cal
orim
eter
Muo
n D
etec
tor
EM
Cal
orim
eter
Solenoid yoke + Hadronic Calorimeter
Solenoid yoke + Muon Detector
HT
CC
RIC
H
Cerenkov
Tracking
5 m solenoid
3° beam (crab) crossing angle
TOF (+ DIRC ?)
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
MEIC interaction region and central MEIC interaction region and central detector layoutdetector layout
Apertures for small-angle ion and electron detection not shown
15
solenoid
electron FFQs50 mrad
0 mrad
ion dipole w/ detectors
(approximately to scale)
ions
electrons
IP
ion FFQs
2+3 m 2 m 2 m
(“full-acceptance” detector)
Three-stage strategy using 50 mrad crossing angle
Detect particles with angles below 0.5° using 20 Tm dipole beyond ion FFQs.
Distance IP – ion FFQs = 7 m(Driven by push to 0.5 degrees detection before ion FFQs)
detectors
Central detector, more detection space in ion direction as particles have higher momenta.
Detect particles with angles down to 0.5° (10 mrad) before ion FFQs.
Need 2 Tm dipole (for 100 GeV proton beams) in addition to central solenoid.
16Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Forward Ion DetectionForward Ion Detection
17
326269
Thu Jul 15 22:13:10 2010 OptiM - MAIN: - C:\Working\ELIC\MEIC\Optics\Disp_Figure8_rel\Ring_13_period_1.opt
65
00
1-1
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y73.59280
Thu Jul 15 22:14:56 2010 OptiM - MAIN: - C:\Working\ELIC\MEIC\Optics\5GeV Electe. Ring\Spin_rotator_match_7_IR.
65
00
1-1
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
348.93239
Thu Jul 15 22:52:10 2010 OptiM - MAIN: - C:\Working\ELIC\MEIC\Optics\Ion Ring_900\Arc_Straight_IR_Str_90_in_2.o
26
00
0
5-5
BE
TA
_X
&Y
[m]
DIS
P_
X&
Y[m
]
BETA_X BETA_Y DISP_X DISP_Y
IP
electrons
ions
8 m drift space after low-Q2 tagger dipole
Chromaticity Compensation
Block
IR
Spin Rotator
Arc end
Chromaticity Compensation BlockArc end
Very forward ion tagging
20 Tm analyzing
dipole
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
MEIC Interaction Region – forward MEIC Interaction Region – forward taggingtagging[Bogacz 10]
-10000
-8000
-6000
-4000
-2000
0
2000
4000
6000
8000
10000
-20000 -15000 -10000 -5000 0 5000 10000 15000 20000x [cm]
z [cm]
Figure-8 Collider Ring - Footprint
Present thinking: ion beam has 50 mr horizontal crossing angle
Renders good advantages for very-forward particle detection
20 Tm dipole @ ~20 m from IP
(Reminder: MEIC/ELIC scheme uses 50 mr crab crossing)
18Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Use Crab Crossing for Very-Forward Use Crab Crossing for Very-Forward DetectionDetection
[Zhang09+]
ionsions
• From arc where electrons exit and magnets on straight section
Synchrotron radiation Synchrotron radiation
Random hadronic backgroundRandom hadronic background
• Dominated by interaction of beam ions with residual gas in beam pipe between arc and IP
• Comparison of MEIC (at s = 4,000) and HERA (at s = 100,000)
− Distance from ion exit arc to detector: 50 m / 120 m = 0.4
− Average hadron multiplicity: (4000 / 100000)1/4 = 0.4
− p-p cross section (fixed target): σ(90 GeV) / σ(920 GeV) = 0.7
− At the same ion current and vacuum, MEIC background should be about 10% of HERAo Can run higher ion currents (0.1 A at HERA)o Good vacuum is easier to maintain in a shorter section of the ring
• Backgrounds do not seem to be a major problem for the MEIC
− Placing high-luminosity detectors closer to ion exit arc helps with both background types
− Signal-to-background will be considerably better at the MEIC than HERAo MEIC luminosity is more than 100 times higher (depending on kinematics)
Backgrounds and detector placementBackgrounds and detector placement
19Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011[R. Ent 10]
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
2 4 6 8
1.902 m
1.719 m
12 14
D=120 mm
5.475 m
16IP
Combined function:1.6 m, 2.230 T, -109 T/m=4 mrad
4.50 m=10 mrad
pc/2.5
1.9 cm (po/2.5)ZDC
=10 mrad=4 mrad
1.1m
1.045 m
1.95 m
1.057 m
neutronsbeam
D=120 mm
10
20
eRHIC - Geometry high-lumi IR with β*=5 cm, l*=4.5 mand 10 mrad crossing angle
Interaction Region configuration Interaction Region configuration for eRHICfor eRHIC
[Aschenauer 11]
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
The New PheniX SpectrometerThe New PheniX Spectrometer
21
e-p/A
4x100
central armunidentified
North armonly muons
Forward upgradeidentified hadrons
5 GeVx50GeV 20 GeV x 250 GeV
No dependence on hadron beam energy
Q2>0.1GeV2
4GeV >5o
10GeV >2o
20GeV >1o
New PheniX has close to full coverage for scattered lepton
Design completely driven by AA, dA and pp physics program [Aschenauer 11]
Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
The new STAR DetectorThe new STAR Detector
MRPC ToF MRPC ToF BarrelBarrel
BBC
FPD
FMS
EMC Barrel
EMC End Cap
DAQ10DAQ100000 COMPLETE
R&D
TPC
computing
HFHFTT
FGFGTT
MTDMTD
Roman Pots Phase 2
Trigger and DAQ Upgrades
Ongoing
• The new Detector matches kinematics of eRHIC
– Particle ID, sufficent pT resolution, etc. at mid-rapidity
– Upgrades in forward direction: increase capability at lower momentum
22
[Aschenauer 11]
SummarySummary
Tanja Horn, EIC@JLab - taking nucleon structure beyond the valence region, INT09-43W 23Tanja Horn, EIC Detectors, INT10-3
• JLab and BNL detector concepts generally similar
• Emphasis on small-angle coverage(̶ Three stage approach for forward hadron detection
• Detector is well suited for a wide range of experiments
• Integration with accelerator important
• Goal: hermetic detector with high resolution over full acceptance
23Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Backup material
Tanja Horn, EIC@JLab - taking nucleon structure beyond the valence region, INT09-43W 24Tanja Horn, EIC Detector Overview, EIC
Advisory Committee 2011
25Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Detector/IR – Forward & Very ForwardDetector/IR – Forward & Very Forward
• Ion Final Focusing Quads (FFQs) at 7 meter, allowing ion detection down to 0.5o before the FFQs (BSC area only 0.2o)
• Use large-aperture (10 cm radius) FFQs to detect particles between 0.3 and 0.5o (or so) in few meters after ion FFQ triplet
x-y @ 12 meters from IP = 2 mm
12 beam-stay-clear 2.5 cm
0.3o (0.5o) after 12 meter is 6 (10) cm
• Large dipole bend @ 20 meter from IP (to correct the 50 mr ion horizontal crossing angle) allows for very-small angle detection (< 0.3o)
x-y @ 20 meters from IP = 0.2 mm
10 beam-stay-clear 2 mm
2 mm at 20 meter is only 0.1 mr…
(bend) of 29.9 and 30 GeV spectators is 0.7 mr = 2.7 mm @ 4 m
Situation for zero-angle neutron detection very similar as at RHIC!
enough space for Roman Pots & small-angle calorimeters
[R. Ent 10]
EIC – Detector R&D ItemsEIC – Detector R&D Items
EM
Cal
orim
eter
Had
ron
Cal
orim
eter
Muo
n D
etec
tor
EM
Cal
orim
eter
Solenoid yoke + Hadronic Calorimeter
Solenoid yoke + Muon Detector
HT
CC
RIC
H
Cerenkov
Tracking
5 m solenoid
DIRC-based PID for EIC Central DetectorCollaboration: JLab, GSI, CUA, ODU
Front end readout module for detector DAQ and trigger system as continuation of 12 GeV efforts Jlab FE group (C. Cuevas)
Improve radiation hardness of Silicon PMTs as continuation of 12-GeV/Hall D workJlab RD&I group (C. Zorn)
Large GEM trackerCollaboration: BNL, Florida Inst. Of Tech., Iowa State, LBNL, MIT, Riken, Stony Brook, Uva, Yale
RICH at high momentaCollaboration: BNL, Florida Inst. Of Tech., Iowa State, LBNL, MIT, Riken, Stony Brook, Uva, Yale
Development of a new detector technology for fiber sampling calorimetersCollaboration: UCLA, Texas A&M, Penn State
26Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Liquid scintillator calorimetry for EICOhio University (J. Frantz)
First Model of eRHIC DetectorFirst Model of eRHIC Detector
E.C. Aschen
auerWorkshop on eRHIC-ePHENIX-eSTAR, March 2010 27
DIRC: not shown because of cut; modeled following Babar no hadronic calorimeter and -ID jet
CALIC technology combines ID with HCAL
EM-CalorimeterPbGl High Threshold
Cerenkovfast trigger on e’e/h separation
Dual-Radiator RICH
as LHCb /HERMES
TraditionalDrift-Chambers
better GEM-Tracker
Central Trackeras BaBar
Si-Vertexas Zeus
Hadronic Calorimeter
[Aschenauer 11]
JLab - Detector Component JLab - Detector Component ModelingModeling
[Collaboration: JLab, GSI, CUA, ODU]
0.4
48
43
m
Q5D5
Q4
90.08703 m
60.0559 m
10
0.2
58
2
m
04/21/23 29
3 m
4.5
=4 mrad10.26m
39.98 m
=10.3255 mrad
10 mrad5.3 m 0
.31
57
26
m3020
=0.0036745 mrad
30 GeV e-
325 GeV p
125 GeV/u ions
eRHIC - Geometry high-lumi IR with β*=5 cm, l*=4.5 mand 10 mrad crossing angle
Interaction Region configuration Interaction Region configuration for eRHICfor eRHIC
[Aschenauer 11]
10 on 60
• Modest (up to ~6 GeV) electron energies in central & forward-ion direction.
• Electrons create showers electron detectors are typically compact.
Scattered Electron KinematicsScattered Electron Kinematics
30Tanja Horn, EIC Detector Overview, EIC Advisory Committee 2011
Low-Q2 electrons in electron endcap
High-Q2 electrons in central barrel: 1-2 < p < 4 GeV
Mo
me
ntu
m (
Ge
V/c
)
Mo
me
ntu
m (
Ge
V/c
)
Electron Scattering Angle (deg) Electron Scattering Angle (deg)
[Horn 08+]
•Larger energies (up to Ee) in the forward-electron direction: low-Q2 events.
Cross section:
Pythia ep: 0.030 – 0.060 mbLuminosity: 1034 cm-1 s-1 = 107 mb-1 s-1
E.C. Aschen
auerWorkshop on eRHIC-ePHENIX-eSTAR, March 2010 31
low multiplicity4-6 √s = 40-65 GeVNch (ep) ~ Nch (eA) < Nch(pA) no occupancy problem
ep
*p
p
Interaction rate:300 -600 kHz
Some thought about ratesSome thought about rates
[Aschenauer 11]