Update on Experiments using SoLID Spectrometer

Transcription

1 Update on Experiments using SoLID Spectrometer Yi Qiang for SoLID Collaboration Hall A Collaboration Meeting Dec 16, 2011

2 Overview SoLID: Solenoidal Large Intensity Device High rate capability: allow for high luminosity Full 2π azimuthal angular acceptance Three experiments approved PVDIS: E SIDIS of polarized 3 He: E and E All rated A by PAC Conditionally approved SIDIS using proton target: PR Instrumentation Update see Zhiwen Zhao s talk 2

3 SoLID Spectrometer 3 PVDIS SIDIS Coil Baffles Gas Cherenkov Coil Heavy Gas Cherenkov GEMs Target GEMs GEMs Target Calorimeter Gas Cherenkov Calorimeter Yoke Calorimeter Yoke Can you find six differences between these panels? Target Location, Baffles (PVDIS), Cherenkov s, GEM Layout, Extra E-Cal, Beam Pipe

4 PVDIS E Motivation 4 Standard Model A PV G FQ 2 a(x) Y (y) b(x) 2 b(x) i i C 2i Q i f i (x) Q i 2 f i (x) d/u for Hydrogen CSV at Quark Level u(x) u p (x) d n (x) d(x) d p (x) u n (x) Di-quarks in the nucleon (Q 2 Dependence) R CSV A PV A PV x ux d x 0.28 x ux dx

5 PVDIS - Statistics vs. Kinematics Strategy: ~0.5% precision over broad kinematic range for sensitive Standard Model test and detailed study of hadronic structure contributions 5 Untangle physics with 1 A A x (1 x) Q 2 [1 HT ] 3 2 CSV Error bar σ A /A(%) shown at center of bins in Q 2, x 4 months at 11 GeV Approved beam time: 169 days 2 months at 6.6 GeV

6 SIDIS - Motivation 6 in DIS Nucleon -> Plate 3-D Tomogr aphy QCD Dynami cs Nucleon Spin TMD Models Quark OAM / Spin TMDs provides 3-D momentum imaging of nucleons in addition to f 1 and g 1 A new phase of study, fast developing field SIDIS: gold mine for all TMDs Transverse motion preserved Lattice QCD QCD Factoriz ation Access all eight leading-twist TMDs through spin-comb. & azimuthal-modulations

7 SIDIS E Measurement of SSA in SIDIS with SoLID on a transversely polarized 3 He <10% d quark tensor charge (Collins moments) Fundamental property of nucleon benchmark test of Lattice QCD 4-D (x,q 2,z,PT) mapping of Sivers moments Orbital Angular Momentum (OAM): Im[(L=0) q (L=1) q ] Search for sign change in Sivers function vs. Drell-Yan Aim for first non-zero Pretzelosity Moments Direct Probe of relativistic effect and OAM within models SIDIS using SoLID and 3 He Large acceptance and high Luminosity Complete 2π coverage: better angular separation 3 He target: > 60% polarization, L(n) cm -2 s -1 Measuring cross section ratios on p, d, 3 He Study factorization, PT dependence, and FSI Collins Effect Sivers Effect 7

8 SIDIS E SIDIS using Longitudinally Pol. 3He and SoLID Extraction of novel TMDs Many predictions available First Lattice QCD calculation Light-cone quark model and others No GPD Correspondence A A A UL LT LL (sin(2 )) g 1L 1L Sign of intrinsic transverse motion Links to Collinear PDFs h h h S h (cos( )) q(1) 1L q(1) 1T ( x) WW type WW type g ( x) x x 1 x 1 2 x dy g y dy h 2 y q 1 q 1 ( y ) g ( y) 1T WORM-GEAR distributions, interference of OAMs: Re[(L=0) q (L=1) q ] p T dependent helicity distribution g 1T h 1L Lattice QCD, arxiv: h 1L (1) P-D int. S-P int. Light-Cone CQM, arxiv:

9 Ultimate Precision 4-D Mapping Example projections of Neutron Collins moments, 1 of 48 z-q2 panels, over 1000 bins for each asymmetry. Expected Improvement of Sivers Function From A. Prokudin Astat. 0.5% (absolute neutron asy.) Asys./A 6% (relative) <10% d quark tensor charge E : 90 days E : 35 days 9

10 SIDIS PR SIDIS Using SoLID and a Transversely Polarized Proton Target Perfect complementary experiment to 3 He SoLID SIDIS experiments: same coverage, similar statistics Conditionally approved on target Beam line similar to g2p/gep configuration JLab/UVa/SLAC polarized target, used in many different experiment (SANE, RSS etc..) o 3cm long NH 3 target o 5 Tesla superconducting magnet o Dynamic Nuclear Polarization(DNP) using microwave pumping o Target magnet optimized for longitudinal setting Need new magnet with larger opening angle to cover entire phase space Spin-flip using Adiabatic Fast Passage (AFP) technique Plans to improved packing fraction (using target disks instead of beads) 10

11 Collaboration International Collaboration: 8 countries, 50+ institutions Rapid growth in US-China collaboration Magnet/Support/Simulations (Argonne/Duke/UVa/Umass) Tracking (UVa/Caltech/Tsinghua/USTC/CIAE/LanzhouU) Gas Cherenkov(Temple/Duke/Stony Brook) EM Calorimeter (UVa/Los Alamos/WM) TOF with MRPC (Tsinghua/Duke) DAQ and Trigger (Jlab/UMass) Polarimetry (UVa) Targets (Jlab/UVa) Infrastructure (Jlab/Duke) 11

12 Progress/Plan Design of all subsystems are all progressing well. See Zhiwen s talk for more hardware update. Some hardware beam tests are scheduled. New collaborators joined: Stony Brook group: Cherenkov detector/gem William Mary group: Calorimeter Regular collaboration meetings. Physics division brainstorming meeting in Sep went well. Next one on Jan Preparing for Jlab director s review. Informal contact with DOE. 12

13 BACKUP SLIDES

14 PVDIS Sensitivity - C1 and C2 Plots 14

15 Slide from A. Prokudin 15

16 From A. Puckett SBS vs. SoLID 16

17 About <10% d quark Tensor Charge 17 Precision is not directly limited by statistical precision. However, Precision is essential to control systematic uncertainties (SIDIS factorization, P T dependence, Higher Twist Contribution ) Based on current knowledge, expect to control systematic uncertainty down to 7-15%. Need data to tell us the final number! 10% is a the goal for our data.

18 Tensor Charge Determination 18 For u and d quark, the covered x range is about (assuming a W>2.0 and W >1.5 cut). Contribution from is about 1% (u) and 4% (d) (Torino Group) Contribution fom is about 1.5% (u) and 0.2% (d) Quoting 3-4% in total for contribution in unmeasured region.

19 Performance of 3 He Target High luminosity: L(n) = cm -2 s -1 Polarization in all 3 directions (L, T, V) Record high in-beam ~ 60% polarization Fast spin flip (every 20 minutes) 19