SoLID SIDIS Update Zhiwen Zhao University of Virginia For SoLID Collaboration Hall A Collaboration Meeting 2013/12/17
Download ReportTranscript SoLID SIDIS Update Zhiwen Zhao University of Virginia For SoLID Collaboration Hall A Collaboration Meeting 2013/12/17
SoLID SIDIS Update Zhiwen Zhao University of Virginia For SoLID Collaboration Hall A Collaboration Meeting 2013/12/17 SoLID (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 rate High dose High field 2 Leading-Twist TMD PDFs 3 Quark polarization Unpolarized (U) Nucleon Polarization U f1 = Boer-Mulders g1 = h1L = Helicity Worm Gear h1 =Collins/Transversity f 1T = g1T = Sivers Nucleon Spin Transversely Polarized (T) h1 = L T Longitudinally Polarized (L) Worm Gear Quark Spin h1T = Pretzelosity Semi-Inclusive DIS (SIDIS) 3-D Tomogr aphy Precision mapping of transverse momentum dependent parton distributions (TMD) Nucleon Spin Models TMD QCD Dynami cs Lattice QCD 4 Quark OAM / Spin QCD Factoriz ation TMD links: 1. Nucleon spin 2. Parton spin 3. Parton intrinsic motion 1 N N AUT ( , ) P N N Collins Sivers AUT sin(h S ) AUT sin(h S ) l h l S ty AUPretzelosi sin(3h S ) T SoLID: 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 days E12-11-007: SIDIS on Longitudinally polarized 3He @ 35 days LOI-12-13-002: Dihadron SIDIS on transversely polarized 3He E12-11-108: SIDIS on transversely polarized proton @ 120 days 5 SoLID SIDIS Setup 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) 6 Requirement 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 7 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 Radiation and Luminosity Estimation PVDIS SIDIS He3 Beam 50uA 15uA Target LD2 40cm 10amg He3 40cm 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 1.27e39 3e36 1e37 3.7e36 1.27e39 6.7e36 baffle target window collimator Window Luminosity (target) Luminosity (window) Luminosity (total) Comment Updated simulation with full background 8 SIDIS 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 target collimator Zhiwen Zhao, Xin Qian 9 SIDIS He3 Electron Trigger • FAEC: Radius and momentum dependent trigger threshold to select DIS electron by cutting on the line of Q2=1 10 DIS electron (Q2>1, W>2) acceptance on FAEC with SoLID CLEO magnet and 40cm target • LAEC: Trigger at 3GeV Pion trigger eff. VS Mom 1GeV 2GeV 3GeV 4GeV 5GeV 3GeV 4GeV 5GeV Electron/photon trigger eff. VS Mom 1GeV Jin Huang, Zhiwen Zhao 2GeV SIDIS 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 background Trigger eff. VS Mom electron pion Jin Huang, Zhiwen Zhao photon proton 11 SIDIS 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 12 SIDIS He3 LGCC Background Rate Low energy background rate 6.6MHz Hadron (from target) accidental rate 2MHz Michael Paolone 13 SIDIS 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 Energy deposit in SPD for electron (blue), pion (red) and gamma (black) Fired layer count in MRPC for charged particle (blue) and gamma (red) Zhihong Ye, Jin Huang, Zhiwen Zhao 14 SIDIS 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 15 SoLID HGCC Design Update Mehdi Meziane 16 SoLID 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 17 Gluon Study Using J/ψ J / (1S ) : I G J PC 0 1 18 M J / 3.097GeV 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 SoLID J/ψ Setup (E12-12-006) e p → e′ p′ J/ψ(e- e+) γ p → p′ J/ψ(e- e+) • Detect decay e- e+ pair • Detect (or not) scattering e for electroproduction (or photoproduction) • Detect recoil p to be exclusive 19 DVCS and TCS: access the same GPDs Spacelike Deeply Virtual Compton Scattering γ*p → γ p′ Timelike Compton Scattering γ p → γ*(e- e+) p′ Information on the real part of the Compton amplitude can be obtained from photoproduction of lepton pairs using unpolarized photons 20 20 SoLID TCS Setup (LOI-12-13-001) γ p → p′ γ*(e- e+) e p → e′ p′ γ*(e- e+) • Detect decay e- e+ pair • Detect recoil p to be exclusive • Cut on missing momentum and mass to ensure quasi-real process 21 Summary 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 22