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New results on Neutron Single Target Spin Asymmetries from Transversely polarized 3 He target at Jlab Nilanga Liyanage, University of Virginia Recent SSA Results from JLab Hall A with a Transversely Polarized 3 He (n) Collins/Sivers Asymmetries on pi+/pi- (published) Worm-gear II Asymmetries on pi+/pi- (published) New Preliminary SSA Results from JLab Hall A with a Transversely polarized 3 He (n) Collins/Sivers Asymmetries in K+/K- Pretzelosity Asymmetries on +/ - Inclusive hadron SSA Inclusive electron SSA (DIS, QE) TMD study at JLab 12 GeV in Hall A: SoLID Program on SSA/TMDs: 3 Approved Experiments on 3 He and p Acknowledgement: thanks to J.P Chen and Jefferson lab Transversity collaboration for some slides

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Unpolarized Structure Function F 2 Bjorken Scaling Scaling Violation Gluon radiation – QCD evolution NLO: Next-to-Leading-Order One of the best experimental tests of QCD

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Parton Distribution Functions (CTEQ6) JHEP 1001: 109 (2010)

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Polarized Structure functions

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Polarized Parton Distributions DSSV, PRL101, 072001 (2008)

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3-D Structure Generalized Parton Distributions Transverse Momentum-Dependent Distributions The next Frontier

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TMDs 2+1 D picture in momentum space Bacchetta, Conti, Radici GPDs 2+1 D picture in impact-parameter space QCDSF collaboration Towards Imaging - Two Approaches intrinsic transverse motion spin-orbit correlations- relate to OAM non-trivial factorization accessible in SIDIS (and Drell-Yan) collinear but long. momentum transfer indicator of OAM; access to Ji’s total J q,g existing factorization proofs DVCS, exclusive vector-meson production

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Transverse Spin: Transversity Three twist-2 quark distributions: Momentum distributions: q(x,Q 2 ) = q ↑ (x) + q ↓ (x) Longitudinal spin distributions: Δq(x,Q 2 ) = q ↑ (x) - q ↓ (x) Transversity distributions: δq(x,Q 2 ) = q ┴ (x) - q ┬ (x) It takes two chiral-odd objects to measure transversity Semi-inclusive DIS Chiral-odd distributions function (transversity) Chiral-odd fragmentation function (Collins function) TMDs: (without integrating over P T ) Distribution functions depends on x, k ┴ and Q 2 : δq, f 1T ┴ (x, k ┴,Q 2 ), … Fragmentation functions depends on z, p ┴ and Q 2 : D, H 1 (x,p ┴,Q 2 ) Measured asymmetries depends on x, z, P ┴ and Q 2 : Collins, Sivers, … (k ┴, p ┴ and P ┴ are related)

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Leading-Twist TMD PDFs f 1 = f 1T = Sivers Helicity g 1 = h1 =h1 = Transversity h1 =h1 =Boer-Mulders h 1T = Pretzelosity g 1T = Worm Gear h 1L = Worm Gear : Probed with transversely pol target HERMES, COMPASS, JLab E06-010 Nucleon Spin Quark Spin

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Separation of Collins, Sivers and pretzelocity effects through angular dependence

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Operated by the Southeastern Universities Research Association for the U.S. Department of Energy Thomas Jefferson National Accelerator Facility COMPASS Sivers asymmetry 2010 data x > 0.032 region - comparison with HERMES results

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E06 ‑ 010 Experiment Spokespersons: Chen/Evaristo/Gao/Jiang/Peng First measurement on n ( 3 He) Polarized 3 He Target Polarized Electron Beam, 5.9 GeV BigBite at 30º as Electron Arm – P e = 0.7 ~ 2.2 GeV/c HRS L at 16º as Hadron Arm – P h = 2.35 GeV/c – Excellent PID for /K/p 7 PhD Thesis Students (All graduated) + new students 12 Beam Polarimetry (Møller + Compton) Luminosity Monitor

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Published Results (I) from JLab Hall A E06-010 with a Transversely Polarized 3 He (n) Collins/Sivers Asymmetries on +/ - X. Qian at al., PRL 107:072003(2011)

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E06-010 3 He Target Single-Spin Asymmetry in SIDIS 3 He Sivers SSA: negative for π +, 3 He Collins SSA small Non-zero at highest x for + Blue band: model (fitting) uncertainties Red band: other systematic uncertainties

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Results on Neutron Collins asymmetries are not large, except at x=0.34 Sivers negative Blue band: model (fitting) uncertainties Red band: other systematic uncertainties

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Published Results (II) from JLab Hall A E06-010 with a Transversely Polarized 3 He (n) Worm-Gear II: Trans-helicity on +/ - J. Huang et al., PRL. 108, 052001 (2012).

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Asymmetry A LT Result 3 He A LT : Positive for - To leading twist:

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–Corrected for proton dilution, f p –Predicted proton asymmetry contribution < 1.5% (π + ), 0.6% (π - ) –Dominated by L=0 (S) and L=1 (P) interference Consist w/ model in signs, suggest larger asymmetry Neutron A LT Extraction Trans-helicity

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Preliminary New Results (I) from JLab Hall A E06-010 with a Transversely Polarized 3 He (n) Collins/Sivers Asymmetries on K+/K- Analysis by Y. Zhao (USTC), Y. Wang (UIUC)

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Kaon PID by Coincidence time of flight Cross checked with RICH results K+/π+ ratio: ~5% K-/π- ratio: ~1%

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Preliminary K+/K- Collins and Sivers Asymmetries on 3 He

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Preliminary New Results (II) from JLab Hall A E06-010 with a Transversely Polarized 3 He (n) Pretzelosity on +/ - Analysis by Y. Zhang (Lanzhou) and X. Qian (Caltech)

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Pretzelosity on +/ - Preliminary

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Extracted Results on Neutron

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Preliminary New Results (III)from JLab Hall A E06-010 with a polarized 3 He (n) Inclusive Electron SSA Analysis by J. Katech(W&M), X. Qian (Caltech)

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Inclusive Target Single Spin Asymmetry: DIS 3 He θ e-e- Unpolarized e - beam incident on 3 He target polarized normal to the electron scattering plane. However, A y =0 at Born level, sensitive to physics at order α 2 ; two-photon exchange. In DIS case: related to integral of Sivers Physics Importance discussed in A. Metz and M. Schlegel’s talks (Tuesday)

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Inclusive Target Single-Spin Asymmetry Extracted neutron SSA Vertically polarized target

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Future: TMD study with SoLID at 12 GeV JLab Hall A Precision 4-D mapping of Collins/Sivers/Pretzelosity Worm-Gear I/II with Polarized 3 He (Neutron) and Proton

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JLab 12 GeV Era: 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 ┴,Q 2 ) Multi-facilities, global effort Precision high statistics high luminosity and large acceptance

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SoLID for SIDIS/PVDIS with 12 GeV JLab Exciting physics program: Five approved experiments: three SIDIS “A rated”, one PVDIS “A rated”, one J/Psi “A- rated” International collaboration: eight countries and 50+ institutions CLEOII Magnet GEMs for tracking Cherenkov and EM Calorimeter for electron PID Heavy Gas Cherenkov and MRPC (TOF) for pion PID

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E12-10-006/E12-11-108, Both Approved with “A” Rating Mapping of Collins(Sivers) Asymmetries with SoLID Both + and - Precision Map in region x(0.05-0.65) z(0.3-0.7) Q 2 (1-8) P T (0-1.6) <10% d quark tensor charge Collins Asymmetry

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Map Collins and Sivers asymmetries in 4-D (x, z, Q 2, P T )

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Expected Improvement: Sivers Function Significant Improvement in the valence quark (high-x) region Illustrated in a model fit (from A. Prokudin) f 1T =

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E12-11-107 : Worm-gear functions (“A’ rating: ) Spokespersons: Chen/Huang/Qiang/Yan Dominated by real part of interference between L=0 (S) and L=1 (P) states No GPD correspondence Lattice QCD -> Dipole Shift in mom. space. Model Calculations -> h 1L =? -g 1T. h 1L = g 1T = Longi-transversity Trans-helicity Center of points:

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Future: TMD study with SoLID at 12 GeV JLab Hall A New Letter Of Intent: Dihadron Production

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Measure Transversity via Dihadron with SoLID LoI submitted to Jlab PAC 40, J. Zhang, A. Courtoy, et al. Wide x b and Q 2 coverages Projected Statistics error for one (M ,z ) bin, integrated over all y and Q 2. Precision dihadron ( +/ -) production on a transversely polarized 3 He (n) Extract transversity on neutron Provide crucial inputs for flavor separation of transversity

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Projected Statistics Error Hall A, SoLID program Polarized 3 He target, (~60% polarization) Lumi=10 36 (n)/s/cm 2 Wide x b and Q 2 coverages Bin central values labeld on axises 4-d (x b, Q 2, Z + -,M + - ) mapping Z scale (color) represent stat. error

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Summary SSA and TMD study have been exciting and fruitful Recent and Preliminary Results from JLab Hall A with a transversely polarized 3 He (n) target Collins/Sivers asymmetries for +/ -/K+/K- Pretzelosity on pi+/pi- SSA: inclusive hadron SSA: inclusive electron DIS SSA: inclusive electron (Quasi)Elastic Planned SoLID program with JLab12 Precision 4-d mapping of TMD asymmetries

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