Precision Study of the Nucleon’s 3D
Structure with SoLID
Zhihong Ye
Seminar Talk at Argonne National Lab, 06/26/2015
Outline
 Unified view of Nucleon Structure
 Study of Transverse Momentum Distributions with SIDIS
 Study of Generalized Parton Distributions with DVCS
 Introduction to SoLID
 Summary
2
Wpu(x,kT,rT ) Wigner distributions
d2rT
d2kT
TMD PDFs
f1u(x,kT), ..
h1u(x,kT)
GPDs/IPDs
3D
d2kT
PDFs
f1u(x), ..
h1u(x)
5D
dx & Fourier Transformation
d2rT
1D
Form
Factors
GE(Q2),
GM(Q2)
3
from Sivers
Function
Wpu(x,kT,rT ) Wigner distributions
d2rT
TMD PDFs
f1u(x,kT), ..
h1u(x,kT)
Transverse Momentum Space
5D
from GPD-H
d2kT
GPDs/IPDs
3D Nucleon Imaging
Impact Parameter Space
4
Transverse Momentum
Distributions
5
TMDs
 Leading-Twist TMDs
8 TMDs with different polarization direction of nucleons and quarks
Become 1D PDFs after integrating on kT.
6
Probe TMDs with SIDIS
 Semi-Inclusive Deep Inelastic Scattering (SIDIS):
d
dxB dydzdS dh dPT2
q  l  l'
Q 2  q 2  4 El El ' sin 2  2
e’
e
p,K
Q2
qP
xB 

2Mv
M
E  El ' q  P
y l

El
lP
P  Ph
z
Pq
pP
PT  2 h
q
Detect scattered electrons
and produced hadrons in the
final state
7
Probe TMDs with SIDIS
 Semi-Inclusive Deep Inelastic Scattering (SIDIS):
All TMDs can be extracted
from SIDIS :
y2
2
d


2
2
dxB dydzdS dh dPT xyQ 2( 1   )
Unpolarized
{ FUU ,T  ...
BoerMulders
cos( h )
 ...
  cos( 2h )  FUU
 S L [  sin( 2h )  FULsin( 2h )  ...]
Transversity
Polarized Target
 ST [  sin( h  S )  FUTsin( h S )  ...
Pretzelocity
 sin( h  S )  ( FULsin( h S )  ...)
Sivers
  sin( 3h  S )  ( FULsin( 3h S )  ...)]
LongTransversity
Helicity
 S L e [ 1   2  FLL  ...]
TransHelicity
 ST e [ 1   2 cos( h  S )  FLTcos( h S )  ...]}
S L / ST
Longitudinally/Transversely Polarized Target
e
Polarized Beam
and Target
Polarized Beam
8
Probe TMDs with SIDIS
 Transversely polarized target Single Spin Asymmetry (SSA):
Separation of Collins, Sivers and pretzelosity effects
through azimuthal angular dependence:
1 N  N
AUT ( ,  ) 
P N  N
Collins
Sivers
 AUT
sin(h  S )  AUT
sin(h  S )
l
h
l
S
ty
 AUPretzelosi
sin(3h  S )
T
UT: Unpolarized beam + Transversely polarized target
Collins
AUT
 sin(h  S )
Sivers
AUT
 sin(h  S )
UT
UT
 h1  H1
 f1T  D1
AUPretzelosity
 sin(3h  S )
T
UT
 h1T  H1
Transversity
Sivers
Prezelosity
+Fragmentation Functions
(obtained from (e+,e-) data)
 Double-Spin Asymmetry (DSA). e.g.:
WormGear
ALT
 cos(h  s )
LT
 g1T  D1
Worm-Gear
Probe TMDs with SIDIS
 Transverse SSA results at Hall-A with 6 GeV:
Blue band: model (fitting) uncertainties
Red band: other systematic uncertainties
X. Qian et al. (Hall A Collaboration) PRL 107 072003 (2011)
10
Probe TMDs with SIDIS
 In the 12GeV Era:
 Explorations:
HERMES, COMPASS, RHIC-spin, Jlab-6GeV,…
 From exploration to precision study
JLab12: valence region; EIC: sea and gluons
 Transversity: fundamental PDFs, tensor charge
 TMDs: 3-d momentum structure of the nucleon
 information on quark orbital angular momentum
 information on QCD dynamics

Multi-dimensional mapping of TMDs
 Precision  high statistics
– high luminosity and large acceptance
SoLID+11GeV
 E12-10-006 (A), SIDIS with Transversely Polarized He3, 90 days
 E12-11-007 (A), SIDIS with Longitudinally Polarized He3, 35 days
 E12-11-108 (A), SIDIS with Polarized Proton, 120 days
11
SoLID-SIDIS Phase Space Coverage
 E12-10-006 (A), SIDIS with Transversely Polarized He3, 90 days
 E12-11-007 (A), SIDIS with Longitudinally Polarized He3, 35 days
 E12-11-108 (A), SIDIS with Polarized Proton, 120 days
•
Natural extension of E06-010
•
Much wider phase space
•
Both transversely and
longitudinally polarized target
12
SoLID-SIDIS
 SIDIS: 4-D (x, pt, Q2, z) probe of nucleon transverse momentum distributions (TMDs)
 SoLID-SIDIS studies TMDs with extensive coverage and resolutions (48 Q-z bins)
One Typical Bin to show the good statistics
> 1400 data points!
13
Transversity to Tensor Charge
Tensor Change: Lowest moment of transversity
•
Fundamental quantity
•
Beyond Standard model searches:
parameters depend on precision of tensor charge
Global model fits to experiments (SIDIS and e+e-)
14
Sivers Function
 The distribution of unpolarised parton in a transversely polarized neutron
 Significant Improvement in the valence quark (high-x) region
Future EIC
With future SoLID-SIDIS data
Illustrated in a model fit
(from A. Prokudin, no QCD
evolution included but soon)
Sign change between SIDIS and Drell-Yan

1
2
T
f ( x, k )
SIDIS

1
  f ( x, k )
2
T
DrellYan
SIDIS  quark in the final state
DY  quark in the initial state
Test the QCD TMD factorization
15
Pretzelocity & Worm-Gear
 Access the orbital angular momentum (OAM) of quarks and gluons with transverse n/p
Pretzelocity: L=0 and L=2 interference (S-D int.)
L=1 and L=-1 interference (P-P Int)
Worm-Gear: L=0 and L=1 Interference.
16
Generalized Parton
Distributions
17
5D
Wpu(x,kT,rT ) Wigner distributions
d2rT
d2kT
TMD PDFs
f1u(x,kT), ..
h1u(x,kT)
GPDs/IPDs
(X. Ji, D. Mueller, A. Radyushkin)
3D
d2kT
PDFs
f1u(x), ..
h1u(x)
dx & Fourier Transformation
d2rT
1D
Form
Factors
GE(Q2),
GM(Q2)
18
GPDs


Generalized Parton Distributions (GPD):
Encode Information of the parton distribution in both the
transverse plane and longitudinal direction.

Four GPDs for quarks or gluons:
~
~
H q/ g , Eq/ g , H q/ g , E q/ g

Connect to FF & PDFs: e.g.

1
 dxH
0
1

0
1

0
1

0
( x,  , t )  F1q (t )
•
dxE q ( x,  , t )  F2q (t )
•
q
~
dxH q ( x,  , t )  g Aq (t )
x  Longitudinal quark momentum fraction
(not experimental accessible)
ξ  Longitudinal momentum transfer. In Bjorken limit:
ξ = xB/(2-xB)
t  Total squared momentum transfer to the nucleon:
t = (P-P’)2
 Angular Momentum Sum Rule (Ji’s Sum Rule):
Ji’s Nucleon Spin Decomposition:
~
dxE q ( x,  , t )  g Pq (t )
H q ( x,0,0)  q( x), x  0
~
H q ( x,0,0)  q( x), x  0
1
1
 J q  J g    Lq  J g
2
2
Jq/ g
(X. Ji, PRL 78, 610 (1997)
1 1
q/ g
  dx  x[ H ( x,  ,0)  E q / g ( x,  ,0)]
2 1
With quark spin measured by DIS, GPD can probe
quark’s O.A.M!
19
GPD Study with DVCS

Deeply Virtual Compton Scattering (DVCS):
d
2


 I   BH
DVCS
dQ 2 dxB dtd
 Interference-Term:
I

*
DVCS BH

e  p / n  e'  p / n  
2
2
*
DVCS BH

 BH  from Nucleon FF, F1 & F2
DVCS
Bethe-Helter
Access GPDs via DVCS by measuring the Ф
dependence of DVCS & Interference Terms
 Compton Form Factor (CFF):
 DVCS
Re(H)
Im(H)
1 H ( x,  , t )
H ( x,  , t )

dx  P 
dx  ipH ( ,  , t ),
1 x    i
1
x 
1
DVCS accesses GPDs at x=ξ
(combine with other channels
to fully map out GPDs)
(Total Eight CFFs)
 In the asymmetry:
A
I
 DVCS  I   BH
2
2
   
 
  
σ+/-, Beam or/and Target Polarization.
20
GPD Study with DVCS
 DVCS with polarized electron beam and targets:
21
GPD Study with DVCS
 DVCS with polarized electron beam and targets:
Approved 12GeV DVCS experiments:





E12-06-114 (Hall-A)
unpol. proton, absolute XS & BSA, limited coverage
E12-13-010 (Hall-C)
unpol. proton, absolute XS &π0, limited coverage.
E12-06-119 (Hall-B)
longi. pol proton (DNP), BSA, TSA, wide coverage
C12-12-010 (Hall-B) conditional approved
trans. pol. proton (HDice), TSA,BSA, wide coverage
E-12-11-003 (Hall-B)
unpol. neutron, BSA
No polarized neutron-DVCS experiment has
been done or proposed at Jlab!
(only done at HERMES with poor accuracy and
limited coverage)
SoLID can bring:
GPDs study needs neutron data (flavor decomposition)!
 Transversely polarized neutron-DVCS (He3, with E12-10-006 SIDIS setup)
new proposal under development (see next few slides), will be summited in 2016
 Longitudinally polarized neutron-DVCS (He3, with E12-11-007 SIDIS setup)
 Transversely polarized proton-DVCS (DNP, with E1211-108 SIDIS setup)
 Longitudinally polarized proton-DVCS (DNP)
22
DVCS with Polarized He3
 Acceptance
Recoil neutrons:
(1) at large angles
(2) P~0.4GeV/c
It will be very
difficult to
detect neutrons
23
DVCS with Polarized He3
 Kinematic Coverage
 Integrated Rate:
24
DVCS with Polarized He3
 Asymmetry Projection:
21 days on E0=8.8GeV, 48 days on E0=11GeV
25
DVCS with Polarized He3
 All bins for TSA on x at one Q2 bin
Two transversely polarized direction (x->0/180degree, y->90/270 degree), 5-Q2-bins, so:
BSAx5, TSAx5x2, DSAx5x2  25 such kind of plots
26
DVCS with Polarized He3
 Make sure the exclusivity with Missing Mass Reconstruction: e  n  e'  n  
• Main background if not detecting recoil neutrons: (n+γ) from π0 decay
e  n  e  n' p 0 ,p 0    
• Missing Mass Reconstruction: detect electron and photons (angles, momentum/energy)
The spectrum resolution is limited by the EC resolution (~5%)
• Background Subtraction: ECs can detect partial π0 decay events by reconstruction two-photons events
Total
Np 0

Total
NpMC
0
 Accept
NpMC
0
Detect
Np 0
NpTotal
( NpDetect
)
0
0
Real events mixed into the MM spectrum (detected by SoLID)
Total
 Accept
NpMC
( NpMC
)
0
0
MC events in the entire region (within SoLID acceptance)
We will learn from the new
Hall-A 12GeV-DVCS data.
From Hall-A DVCS@12GeV data
27
DVCS with Polarized He3
 Make sure the exclusivity with a Central Recoil Detector
• Hall-B has a design to detect recoil neutrons

Possible candidate: Scintillating Fiber Tracker
 Prototype proposal awarded by JSA 2014 postdoc prize
 A complete testing setup:
A lab, dark-boxes, DAQ, fibers+SiPMs
 Testing light output with varying Fibers and SiPMs
 Working with DarkLight Collaboration to design and
build their Center SFT, which can potentially be used
by nDVCS
 Need careful study to evaluate the detection efficiency
DarkLight Detector Layout
28
Other GPD Studies @ SoLID
 DVCS with transversely polarized proton target (to be proposed in 2016/2017)
 Double-DVCS:



e  p / n  e'  p / n  l   l 
A lepton pair in the final state instead of a real photon
Can access GPDs beyond the x=ξ limit
new LOI submited to 2015-PAC and aimed for a proposal to
2016-PAC
 Timelike-DVCS:
  p / n  p / n  l  l



Inverse of the space-like DVCS
Extract the real part of CFFs
new proposal, run with SoLID-J/Psi
 Deep Virtual Meson Production (both neutr):
e  p / n  e'  p / n  p 0 , /  0 , /  0 , ...
Detect the produced meson (π0,ρ 0, ω 0, …)
Probe individual GPDs more selectively than DVCS
e.g. ρ 0/ρ +K*  H, E, π 0,η 0,KH-tilde, E-tilde
 Invited exports to study the opportunity with SoLID-SIDIS


29
Introduction to SoLID
30
SoLID Overview
 SoLID: Solenoidal Large Intensity Device
High Intensity (1037 ~ 1039 cm-2s-1) and,
Large Acceptance (8<θ<24, 0<Φ<360, 1<Pe<7GeV/c for SIDIS)
Two Configurations
& GPD
31
SoLID Overview
 SoLID: Solenoidal Large Intensity Device
High Intensity (1037 ~ 1039 cm-2s-1) and,
Large Acceptance (8<θ<24, 0<Φ<360, 1<Pe<7GeV/c for SIDIS)
PVDIS: Baffle
SIDIS&J/Psi:
6xGEMs
LGC
LASPD
4xGEMs
LAEC
EC
LGC
HGC
FASPD MRPC FAEC
32
SoLID Overview
 SoLID: Solenoidal Large Intensity Device
High Intensity (1037 ~ 1039 cm-2s-1) and,
Large Acceptance (8<θ<24, 0<Φ<360, 1<Pe<7GeV/c for SIDIS)
 Approved SIDIS Programs:
 E12-10-006 (A), SIDIS with Transversely Polarized He3, 90 days
 E12-11-007 (A), SIDIS with Longitudinally Polarized He3, 35 days
 E12-11-108 (A), SIDIS with Polarized Proton, 120 days
 and bonus runs (Ay, Di-Hadron, and PDFs: A1/A2, g1/g2, d2 …)
 Parity Violation Deep Inelastic Scattering (PVDIS):
 E12-10-007 (169 days, A)
 EMC with Calcium (will be proposed)
 J/ψ : Near Threshold Electroproduction of J/ψ at 11 GeV:
 E12-12-006 (60 days, A-),
 A new run-group proposal submitted: Time-Like Compton Scattering
 Generalized Parton Distributions (GPDs): (new LOIs & Proposals)
polarized-proton/neutron DVCS, Doubly DVCS, DVMP, TCS, etc.
 More e.g., Hadronization
 SoLID has a strong and still expending collaboration: 250+ physicists, 70+
institutions from 13 countries. Significant international contributions ...
33
SoLID-SIDIS Configuration
Large-Angle :
Detect electrons only
Forward-Angle :
Detect electrons
& hadrons
Coverage:
Forward Acceptance: Φ: 2π, θ: 8o-14.8o , P: 1.0 – 7.0 GeV/c,
Large Acceptance:
Φ: 2π, θ: 16o-24o , P: 3.5 – 7.0 GeV/c
Resolution by GEM:
δP/P ~ 2%, θ ~ 0.6mrad, Φ ~ 5mrad
Coincidence Trigger:
Electron Trigger + Hardron Trigger (pions, and maybe kaons)
34
SoLID-DVCS Configuration
Large-Angle : Detect
electrons & photons
Forward-Angle :
Detect electrons
& photons
Mode#2:
Dedicated run with
additional beam-time
 Remove hadron
triggers, HGC ...
Mode#1:
In run group with
SIDIS
 Need to add
the photon trigger
Coverage:
Forward Acceptance: Φ: 2π, θ: 8o-14.8o , P: 1.0 – 7.0 GeV/c,
Large Acceptance:
Φ: 2π, θ: 16o-24o , P: 3.5 – 7.0 GeV/c
Electron Resolution by GEM:
Photon Resolution by EC:
Coincidence Trigger:
δP/P ~ 2%, θ ~ 0.6mrad, Φ ~ 5mrad
~5% in energy, ~1cm in position
Electron Trigger + Photon Trigger
This configuration can still be optimized!
35
SoLID-SIDIS Detectors
GEM
MRPC
Double-mask GEM foil
HGC
LGC
Single-mask GEM foil
EC
36
Magnet
 CLEO-II Solenoid Magnet: Jlab/ANL
CLEO at Cornell
Goals:
Acceptance: P: 1.0 – 7.0 GeV/c, Φ: 2π,
θ: 8o-24o (SIDIS), 22o-35o (PVDIS),
 Resolution: δP/P ~ 2%
 Fringe field at the front end < 5 Gaus
CLEO-II: from Cornell Univ.
Built in 1989 and operated until 2008, uniform
central field at 1.5 T, Inner radius 2.9 m, coil
radius 3.1 m and coil length 3.5 m
Status:
CLEO in Hall-A
 CLEO-II magnet formally requested and agreed in
2013:
 Site visit in 2014, disassembly in 2015 and transport
in 2017
 Design of supporting structures and mounting system
at JLab
37
Triggers&DAQ
 Triggers:
 Estimation based on sophesticated Geant simulation and well-tone physics models
 PVDIS: LGC+EC provide electron triggers, 27 KHz/sector, 30 sectors
 SIDIS: Coincident trigger between electrons and hardrons within a 30 ns window:
LASPD+LAEC provide electron triggers, 25 KHz
66 KHz + 6 KHz (eDIS)
LGC+FASPD+MRPC+FAEC provide electron trigger, 129 KHz
FASPD+MRPC+FAEC provide hadron trigger, 14 MHz
 Read-Out and Data Aquisition System:
 Use fast electronics to handle the high rates
(FADC, APV25, VETROC, etc.)
 Read out EC clusters to reduce background
 Current design can take the trigger rates
60 KHz per sector for PVDIS, and 100 KHz overall for SIDIS
 Use Level-3 to further reduce the events size
 Learn new developments from others (e.g. Hall-D)
EC Trigger
38
Simulation&Software
 Monte Carlo Simulation:
•
•
•
SoLID full setup in GEMC (Geant4) with realistic materials
EM background produced from 11GeV e- on targets with the physics models in Geant4
Hadron background, generated from event generators (Wiser fit) on both target and target
windows, then passed into GEMC
 GEM Tracking Reconstruction:
•
•
•
Can reconstruct charged particles traveling in
the strong magnetic filed
Need fast processing time for high rates with
backgrounds
Two approaches: Tree Search, Progressive
Tracking
 End-to-End Simulation & Analysis Software:



Should be able to handle large scale data analysis
Should be able to mix MC and real data
Should be able to add and change configurations
•
•
Working group has been form – weekly software meeting
Borrow experience from Hall-B/-D and sPHENIX (BNL)
39
Summary
 Understanding the nucleon structure from 1D (PDFs&FF) to 3D (TMDs & GPDs)
 SIDIS provides a powerful tool to study TMDs
8 leading twist TMDs to access quark spin & OAM, tensor change, and so on
 SoLID-SIDIS programs will perform 4D precise measurements of TMDs
Three A rated experiments, two newly approved “bonus” experiments, and more …
 With the similar SoLID-SIDIS setup, we can also study GPDs via DVCS and etc.
Letter-of-Intents and one proposal have been submitted in this PAC.
 With the features of high luminosity and large acceptance, SoLID can explore a wide
range of physics topics.
SoLID Time-Line:
 Pre-Conceptual Design Report submitted in July 2014
 Actively provided inputs for NSAC’s Long-Range-Plan
 JLab Director’s Review in Feb. 2015 (received very positive feedback)
 Resolving and responding important recommendations
 Requesting pre-R&D resources and planning Detector R&D and Software Design
 Preparing for DOE Science Review soon
40
Backup Slides
41
SoLID-SIDIS Detectors
GEM
MRPC
Double-mask GEM foil
HGC
LGC
Single-mask GEM foil
EC
42
Baffle
 PVDIS Baffle: Jlab/ANL/Stone-Brook
PVDIS only
Goals:
 11 layers of 9cm thick lead and one layer of 5cm lead
 Right after the target to block photons, pions and secondary
particles.
 Follow charge particle bending in the field, preserve the same
azimuthal slice and block line of sight.
12th
1st
1nd
5th
6th
7th
10th
11th
9th
3rd
4th
8th
43
Magnet
 CLEO-II Solenoid Magnet: Jlab/ANL
Goals:
Acceptance: Φ: 2π, θ: 8o-24o (SIDIS), 22o-35o (PVDIS),
P: 1.0 – 7.0 GeV/c,
 Resolution: δP/P ~ 2% (requires 0.1 mm tracking resolution)
 Fringe field at the front end < 5 Gaus
CLEO-II: from Cornell Univ.
Built in 1989 and operated until 2008, uniform central field at 1.5 T,
Inner radius 2.9 m, coil radius 3.1 m and coil length 3.5 m
Status:
 CLEO-II magnet formally requested and agreed in 2013:
 Site visit in 2014, disassembly in 2015 and transport in 2017
 Design of supporting structures and mounting system at JLab
CLEO in Hall-A
CLEO at Cornell
44
Detectors
 GEM: USTC/CIAE/Lanzhou/Tsinghua/IMP/UVa
Goals: 5 planes (PVDIS) and 6 planes (SIDIS/JPsi), area~37 m2 (165K outputs),
work in high rate and high radiation environment.
tracking eff.>90%, radius resolution ~ 0.1 mm,
Status: main contribution from Chinese institutions
•
China: CIAE/USTC/Tsinghua/LZU)



100cmx50cm GEM detector has been built and tested
CIAE has made a 40cmx40cm single-mask GEM foil
Continue on read-out electronics desgin and test
40cmx40cm single-mask GEM foil
Single-mask GEM foil
100cmx50cm GEM detector
Double-mask GEM foil
UVa: First full size prototype assembled,
and beam test at Fermi Lab Oct 2013
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Detectors
 Light Gas Cherenkov Counter (LGC): Temple Univ.
Goals:
2 m C02 (SIDIS/Jpsi), 1 atm
1 m C4F8O (65%)+N2 (35%) (PVDIS), 1 atm
30 sectors, 60 mirrors, 270 PMTs,
Area~20m2
N.P.E>10, eff.>90%, π suppresion > 500:1
Work at 200G field (100G after shielding)
Status:
 Support Structure and Mounting Design
 u-metal Shielding design
 Pre-R&D ongoing at Temple
46
Detectors
 Heavy Gas Cherenkov Counter (HGC): Duke Univ./Regina Univ.
Goals:
for SIDIS only
1 m C4F8O at 1.5 atm
30 mirrors, 480 PMTs, area~20 m2
N.P.E>10, eff.>90%, Kaon suppresion > 10:1,
Work at 200G field (100G after shielding)
Status:
 Optimize the design with MC
 Designs of Support Structure,
Mounting, Shielding, etc.
 Magnet field test with MaPMT H8500
(S. Malance, JINST 8 P09004,2013) and H12700
 Prototype-Test will happen at Duke soon
47
Detectors
 Multi-gap Resistive Plate Chamber:
Tsinghua/USTC/Duke
Goals:
Status:
 For SIDIS only, between FASPD and FAEC
 50 super-modules, each contains 3 modules,
1650 strips and 3300 output channels.
 Timing resolution < 100ps
 Works at high rate up to 10 KHz/cm2
 Photon suppression > 10:1
 p/k separation up to 2.5GeV/c
 Prototype Developed at Tsinghua
 Beam test at Hall-A in 2012
 New facility for mass production
 Read-out electronics design
 Resistive glass Aging-Test:
Most recent aging test shows the glass has no
significant effect with neutrons.
48
Detectors
 Electromagnetic Calorimeters (EC): UVa/ANL/W&M/LANL/Shandong Univ.
Goals:
 Shashlyk sampling calorimeters
 1800 modules (2 R.L.) for PreShower, 1800 modules (18 R.L) for Shower
 Modules re-arranged for PDVIS<->SIDIS
 electron eff.>90%, E-Resolution~10%/√E,
π suppresion > 50:1
 Rad. Hard (<20% descreasing after 400K Rad)
49
Detectors
 Scintillating Pedal Detectors (SPD): UVa/ANL/W&M/LANL/Shandong Univ.
Goals:
 For SIDIS only
 Two planes (in front of LAEC and FAEC):
LASPD: 60 modules, 5 mm or thicker, photon rej. 10:1
FASPD: 60 modules x 4 radius, photon rej. 5:1
 LASPD timing resolution < 150ps
Status:
 Design and Simulation
 Pre-R&D at UVa and JLab
50
Detectors
 Electromagnetic Calorimeters (EC): continue ...
Status:
 Sophesticated Geant Simulation
 Active Pre-R&D at UVa and Jlab
 Sample&PMT tests and Pre-Amp design
PreShower module
PVDIS
Fiber connectors
SIDIS (worse case)
51
Detectors
 Scintillating Pedal Detectors (SPD): UVa/ANL/W&M/LANL/Shandong Univ.
Goals:
 For SIDIS only
 Two planes (in front of LAEC and FAEC):
LASPD: 60 modules, 5 mm or thicker, photon rej. 10:1
FASPD: 60 modules x 4 radius, photon rej. 5:1
 LASPD timing resolution < 150ps
Status:
 Design and Simulation
 Pre-R&D at UVa and JLab
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