SoLID SIDIS Update
description
Transcript of SoLID SIDIS Update
SoLID SIDIS UpdateZhiwen Zhao
University of Virginia
For SoLID Collaboration
Hall A Collaboration Meeting2013/12/17
2SoLID (Solenoidal Large Intensity Device)General purpose device, large acceptance, high luminosity
Lumi 1e37/cm2/s (open geometry) 3D hadron structure
TMD (SIDIS on both neutron and proton) (3 EXPs, 1 LOI)
GPD (Timelike Compton Scattering) (1 LOI) Gluon study
J/ production at threshold (1 EXP)
Lumi 1e39/cm2/s (baffled geometry)Standard Model test and hadron structure
PVDIS on both deuterium and hydrogen (1 EXP)
High rateHigh doseHigh field
3
Quark polarization
Unpolarized(U)
Longitudinally Polarized (L)
Transversely Polarized (T)
Nucleon Polarization
U
L
T
Leading-Twist TMD PDFs
f1 =
f 1T =
Sivers
Helicityg1 =
h1 =Collins/Transversity
h1 =
Boer-Mulders
h1T =
Pretzelosity
g1T =
Worm Gear
h1L =
Worm Gear
Nucleon Spin Quark Spin
4Semi-Inclusive DIS (SIDIS)
TMD
Nucleon Spin
QCD Dynamics
Quark OAM / Spin
QCD Factorizatio
n
3-D Tomograph
y
Lattice QCD
Models
Precision mapping of transverse momentum dependent parton distributions (TMD)
1( , )
sin( ) sin( )
sin(3 )
l lUT h S
h SSiverCollins
Pretzelosi
UT
tyU
sUT h S
h ST
N NA
P N
A
A
N
A
TMD links:1. Nucleon spin2. Parton spin3. Parton intrinsic
motion
5SoLID: Precision Study of TMDs
From exploration to precision study with 12 GeV JLab Transversity: fundamental PDFs, tensor charge TMDs: 3-d momentum structure of the nucleon Quark orbital angular momentum Multi-dimensional mapping of TMDs
4-d (x,z,P┴,Q2) Multi-facilities, global effort
Precision high statistics high luminosity large acceptance
E12-10-006: SIDIS on transversely polarized 3He @ 90 daysE12-11-007: SIDIS on Longitudinally polarized 3He @ 35 daysLOI-12-13-002: Dihadron SIDIS on transversely polarized 3HeE12-11-108: SIDIS on transversely polarized proton @ 120 days
6
Tracking: GEM Tracker
Electron Identification:Large angle• EM calorimeter (LAEC)
including Scintillator Pad Detector (SPD)
Forward angle• EM calorimeter (FAEC)
including Scintillator Pad Detector (SPD)
• Light Gas Cerenkov (LGCC)
Pion identification:• Heavy Gas Cerenkov (HGCC)• TOF (MRPC)
SoLID SIDIS Setup
7Requirement of SIDIS
Kinematics Coverage: 0.05 ~ 0.6 in x (valence) 0.3 ~ 0.7 in z (factorization region) PT up to ~ 1 GeV (TMD Physics) Fixed target Q2 coverage 1-8 GeV2 (~ 2 GeV2 in
ΔQ2 at fixed x) Luminoisity:
3He Unpolarized ~ 1037 N/cm2/s NH3 Unpolarized ~ 1036 N/cm2/s
Polarized 3He Target: ~ 60% higher polarization Fast spin flip (<20 mins)
Polarized NH3 Target: Jlab/UVa target with upgraded design of the
magnet Spin flip every two hours average ~70% in-beam polarization Beamline chicane to transport beam through
5T target magnetic field
Electron PID: <1% Pion contamination
(asymmetry point of view) Pion PID:
<1% Kaons and Protons <1% electron contamination
Optics of Reconstruction: < a few % in δP/P < 1 mr in polar angle < 10 mr in azimuthal angle ~ 1-2 cm vertex resolution
DAQ: ~ 3kHz physics coincidence
< 100 kHz coincidence rate
Limits: 300 MB/s to tape
8Radiation and Luminosity EstimationPVDIS SIDIS He3
Beam 50uA 15uA
Target LD2 40cm 10amg He3 40cm
Window Al 2*100um Glass 2*120um
Radiation length (target) 5.4e-2 0.8e-3
Radiation length (window) 2.25e-3 3.4e-3
Radiation length (total) 5.6e-2 4.2e-3
Luminosity (target) 1.27e39 3e36
Luminosity (window) 1e37 3.7e36
Luminosity (total) 1.27e39 6.7e36
Comment baffle target window collimator
Updated simulation with full background
9SIDIS He3 Target Collimator A pair of collimators are optimized to block
background from both target windows into forward angle detectors
The acceptance without (black) and with (red) the collimators
targetcollimator
Zhiwen Zhao, Xin Qian
10SIDIS He3 Electron TriggerDIS electron (Q2>1, W>2) acceptance on FAEC with SoLID CLEO magnet and 40cm target• FAEC: Radius and momentum
dependent trigger threshold to select DIS electron by cutting on the line of Q2=1
• LAEC: Trigger at 3GeV
Jin Huang, Zhiwen Zhao
Pion trigger eff. VS Mom
Electron/photon trigger eff. VS Mom
1GeV 2GeV 3GeV 4GeV 5GeV
1GeV 2GeV 3GeV 4GeV 5GeV
11SIDIS He3 Charged Particle Trigger FAEC only, pion rate drops very quickly at large angle Cut on MIP only to preserve pions and suppress low energy
backgroundTrigger eff. VS Mom
electron photon
pion proton
Jin Huang, Zhiwen Zhao
12SIDIS He3 EC Trigger Rate Need photon suppression by
LGCC, SPD and MRPC Need pion suppression by
LGCC Some of electrons and
positrons from the pair production of gamma from pi0 decay can be suppressed by LGCC,SPD or MRPC depending on where the conversion happens
Jin Huang, Zhiwen Zhao
13SIDIS He3 LGCC Background Rate Low energy background
rate 6.6MHz Hadron (from target)
accidental rate 2MHz
Michael Paolone
14SIDIS SPD and MRPC Photon Rejection SPD or MRPC alone can reach 10:1 rejection Combined together, they can reach ~ 20:1 rejection
due to their correlation
Fired layer count in MRPC forcharged particle (blue) and gamma (red)
Energy deposit in SPD forelectron (blue), pion (red) and gamma (black)
Zhihong Ye, Jin Huang, Zhiwen Zhao
15SIDIS He3 Trigger rate Forward angle electron trigger rate, combining
FAEC,SPD,MRPC and LGCC, 140kHz Large angle electron trigger rate, combining LAEC and
SPD, 20kHz Forward angle charged particle trigger rate, combining
FAEC,SPD and MRPC, 18.7MHz Total coincidence rate ~ 90kHz with 30ns time window
16SoLID HGCC Design Update
Mehdi Meziane
17SoLID GEM Test at Fermi Lab 1m long GEM (largest in the
world) for SoLID built at UVa Successfully tested with
APV25/SRS readout at Fermi Lab in Oct 2013
Kondo Gnanvo
18
J/ψ, a charm-anti-charm system Little (if not zero) common valence quark
between J/ψ and nucleon Quark exchange interactions are strongly
suppressed Pure gluonic interactions are dominant
J/ψ, a probe of the strong color field in the nucleo
Multiple gluon exchange possible near threshold
Not much data available at that region
18
/ (1 ) : 0 1G PCJ S I J / 3.097JM GeV Gluon Study Using J/ψ
?
19SoLID J/ψ Setup (E12-12-006)
• Detect decay e- e+ pair• Detect (or not) scattering e for electroproduction (or photoproduction)• Detect recoil p to be exclusive
e p → e′ p′ J/ψ(e- e+)
γ p → p′ J/ψ(e- e+)
20DVCS and TCS: access the same GPDs
20
Spacelike Deeply Virtual Compton Scattering Timelike Compton Scattering
γ p → γ*(e- e+) p′γ*p → γ p′
Information on the real part of the Compton amplitude can be obtained from photoproduction of lepton pairs using unpolarized photons
21SoLID TCS Setup (LOI-12-13-001)
• Detect decay e- e+ pair• Detect recoil p to be exclusive• Cut on missing momentum and mass to ensure quasi-real process
γ p → p′ γ*(e- e+)
e p → e′ p′ γ*(e- e+)
22Summary
We have made good progress and are ready for the director review in early next year
SoLID SIDIS setup is a general device. More experiments may be proposed to take advantage of its large acceptance and high luminosity features