Jin Huang Los Alamos National Lab Based on PhD thesis work at MIT and Jefferson Lab Hall A For JLab Physics Seminar, Apr 6, 2011

JLab Physics Seminar Jin Huang 2

 Majority mass of visible matter is from nucleons (proton/neutron)  Knowledge of parton constituent’s behavior inside nucleon summarized in Parton Distribution Functions (PDF) ◦ Unpolarized PDF, mapped 5 orders in x range and Q 2 ◦ Longitudinally polarized PDF, mapped 3 orders in x and 2 in Q 2  Orbital momentum play important role in spin structure ◦ Rarely known experimentally, need go multi-D JLab Physics Seminar Jin Huang 3

 TMD PDFs link ◦ Intrinsic motion of partons ◦ Parton spin ◦ Spin of the nucleon  Multi-Dimension structure ◦ Imaging the 3D motion of the quark ◦ Probes orbital motion of quarks  A new phase of study, fast developing field ◦ Great advance in theories (factorization, models, Lattice...) ◦ Experimentally, not systematically studied until recent years JLab Physics Seminar Jin Huang 4

proton lepton antilepton Drell-Yan, Jets… BNL JPARC FNAL EIC proton lepton pion SIDIS electron positron pion e – e + to hadrons Partonic scattering amplitude Fragmentation amplitude Distribution amplitude JLab Physics Seminar 5Jin Huang

JLab Physics Seminar Jin Huang 6 Probability to find a quark q in a nucleon P with a certain polarization in a position r and momentum k Measure momentum transfer to quark. Measure momentum transfer to nucleon. “Parent” Wigner distributions W p q (x,k,r) GPDs H p u (x, ,t), E p u (x, ,t),… GPDs H p u (x, ,t), E p u (x, ,t),… TMDs h 1T (x,k),... TMDs h 1T (x,k),... Form Factors G E,G M,... Form Factors G E,G M,... PDFs Ex. f(x), g 1 (x),... PDFs Ex. f(x), g 1 (x),... (FT)  =0,t=0 Simplified relations between distributions

7 f 1 = f 1T  = Sivers Helicity g 1 = h1 =h1 = Transversity h1 =h1 =Boer-Mulders h 1T  = Pretzelosity JLab Physics Seminar Jin Huang g 1T = h 1L  = Worm Gear (Kotzinian-Mulders) : Survive trans. momentum integration Nucleon Spin Quark Spin Worm Gear (trans-helicity)

8 f 1T  = h1 =h1 = h1 =h1 = h 1T  = Transversity Boer-Mulders Pretzelosity Sivers Helicity f 1 = g 1 = g 1T = JLab Physics Seminar Jin Huang Worm Gear (trans-helicity) : Also accessed in E Nucleon Spin Quark Spin h 1L  = Worm Gear (long-transversity)

9 f 1T  = h1 =h1 = h1 =h1 = h 1T  = Transversity Boer-Mulders Pretzelosity Sivers Helicity f 1 = g 1 = g 1T = JLab Physics Seminar Jin Huang Worm Gear (trans-helicity) : This talk Nucleon Spin Quark Spin h 1L  = Worm Gear (long-transversity)

  Leading twist TMD PDFs T-even, Chiral-even  Dominated by real part of interference between L=0 (S) and L=1 (P) states ◦ Imaginary part -> Sivers effect  No GPD correspondence ◦ a genuine sign of intrinsic transverse motion  Poorly known experimentally JLab Physics Seminar Jin Huang 10 Worm Gear g 1T = TOT g 1T (1) S-P int. P-D int. Light-Cone CQM by B. Pasquini B.P., Cazzaniga, Boffi, PRD78, 2008

 So far using simplified straight gauge links  “Worm-gear” TMDs → dipole Trans Mom. JLab Physics Seminar Jin Huang 11 Spin: Nucleon (T), Quark (L) Spin: Nucleon (L), Quark (T) B. Musch, et. al. arXiv: ; , m π ~500GeV - u d ud

 Active theoretical studies, including modeling  Generic features of model predictions: ◦ valence x region ◦ ~ a few percent w.r.t. unpolarized f 1 ◦ h 1L  q and g 1T q take opposite signs  Models (early stage): ◦ WW-type calculation (shown right)  ◦ Diquark spectator models ◦ Constituent Quark Model (LCCQM) ◦ Covariant Parton Model ◦ Quark-Diquark Model ◦ Bag Model JLab Physics Seminar Jin Huang 12 WW-type LCCQM arXiv: [hep-ph]

 Gold mine for TMDs  Access all eight leading-twist TMDs through spin-comb. & azimuthal-modulations  Tagging quark flavor/kinematics JLab Physics Seminar Jin Huang 13

JLab Physics Seminar Jin Huang 14 f 1 = Sivers f 1T  = Transversity h 1T = Boer-Mulder h1 =h1 = Pretzelosity h 1T  = S L, S T : Target Polarization; e : Beam Polarization h 1L  = Worm Gear g 1T = Worm Gear g 1 = Helicity

 Double Beam-Target Spin Asymmetry (DSA) in SIDIS with transversely polarized target: A LT JLab Physics Seminar Jin Huang 15

g 1 Data + WW relation Diquark Spectator Model JLab Physics Seminar Jin Huang 16 arXiv: v1 A. Kotzinian, etc., PRD (2006)  Models predict few to 20 percent asymmetry for ◦ Neutron A LT at Jlab kinematics

 No measurement until 2002  Preliminary COMPASS results ◦ A LT on proton and deuteron ◦ Fixed beam helicity (μ beam) ◦ Low x, small predicted asymmetry  Preliminary HERMES results ◦ A LT on proton ◦ Reported in Apr  New measurement needed ◦ Different target for flavor decomposition ◦ Higher precision at valence region Proton arXiv: [hep-ex] Preliminary arXiv: [hep-ex]

First neutron A LT measurement Flagship experiment using polarized 3 He target at JLab JLab Physics Seminar Jin Huang 18

JLab Physics Seminar Jin Huang 19  Newport News, Virginia  Linear accelerator provides continuous polarized electron beam ◦ E beam = 6 GeV ◦ P beam = 85%  3 experimental halls  E in Hall A A B C

Institutions (38) Univ. Kentucky, W&M, Duke Univ., CalTech, UIUC, Lanzhou Univ, California State Univ, Univ. Glasgow, MIT, CMU, JLab, ODU, UVa, Hampton Univ, INFN, Mississippi State Univ, Rutgers, Kharkov Inst. of Phys. and Tech., Los Alamos National Lab, Longwood Univ, Cairo Univ, Kyungpook National Univ, China Inst. of Atomic Energy, Kent State Univ, Univ. of Sci. & Tech. of China, Florida International Univ., Univ. Massachusettes, Temple Univ, Univ. Blaise Pascal, Univ. of New Hampshire, Syracuse Univ., Yerevan Physics Inst., Univ. Ljubljana, Seoul National Univ. Collaboration members (115) K. Allada, K. Aniol, J. R. M. Annand, T. Averett, F. Benmokhtar, W. Bertozzi, P. C. Bradshaw, P. Bosted, A. Camsonne, M. Canan, G. D. Cates, C. Chen, J.-P. Chen, W. Chen, K. Chirapatpimol, E. Chudakov, E. Cisbani, J. C. Cornejo, F. Cusanno, M. M. Dalton, W. Deconinck, C.W. de Jager, R. De Leo, X. Deng, A. Deur, H. Ding, P. A. M. Dolph, C. Dutta, D. Dutta, L. El Fassi, S. Frullani, J. Huang, H. Gao, F. Garibaldi, D. Gaskell, S. Gilad, R. Gilman, O. Glamazdin, S. Golge, L. Guo, D. Hamilton, O. Hansen, D.W. Higinbotham, T. Holmstrom, M. Huang, H. F. Ibrahim, M. Iodice, X. Jiang, G. Jin, M. K. Jones, J. Katich, A. Kelleher, W. Kim, A. Kolarkar, W. Korsch, J. J. LeRose, X. Li, Y. Li, R. Lindgren, N. Liyanage, E. Long, H.-J. Lu, D. J. Margaziotis, P. Markowitz, S. Marrone, D. McNulty, Z.-E. Meziani, R. Michaels, B. Moffit, C. Munoz Camacho, S. Nanda, A. Narayan, V. Nelyubin, B. Norum, Y. Oh, M. Osipenko, D. Parno, J. C. Peng, S. K. Phillips, M. Posik, A. J. R. Puckett, X. Qian, Y. Qiang, A. Rakhman, R. D. Ransome, S. Riordan, A. Saha, B. Sawatzky, E. Schulte, A. Shahinyan, M. H. Shabestari, S. Sirca, S. Stepanyan, R. Subedi, V. Sulkosky, L.-G. Tang, A. Tobias, G. M. Urciuoli, I. Vilardi, K.Wang, Y. Wang, B.Wojtsekhowski, X. Yan, H. Yao, Y. Ye, Z. Ye, L. Yuan, X. Zhan, Y. Zhang, Y.-W. Zhang, B. Zhao, X. Zheng, L. Zhu, X. Zhu, and X. Zong JLab Physics Seminar Jin Huang 20 Co-spokesperson, Graduate student, Leading Postdoc

JLab Physics Seminar Jin Huang 21  Successful data taking  Polarized electron beam ◦ With 30 Hz helicity reversal  Polarized 3 He target  BigBite at 30º detect electron ◦ Dipole magnet, P e = 0.6 ~ 2.2 GeV/c ◦ MWDC/shower-preshow/scitillator  HRS L at 16º detect hadron ◦ QQDQ config, P h = 2.35 GeV/c ◦ Scintillator/drift chamber/Cherenkov Beam Polarimetry (Møller + Compton) Luminosity Monitor

Only Small Part of Left-HRS and He-3 Target is Shown JLab Physics Seminar Jin Huang 22

Møller Polarimeter Polarized beam at Jefferson Lab is crucial  Standard Hall A Polarimetry  Polarized e - +e -  e - +e -  Performed per week (invasive)  Overall polarization = %  Fast beam helicity reversal at 30 Hz  Beam charge balance between two helicity states JLab Physics Seminar Jin Huang 23 Beam Polarimetry Luminosity Monitor ‑ 010.html

  High Luminosity polarize target  Compact size: No cryogenic support needed JLab Physics Seminar Jin Huang 24 Beam Polarimetry Luminosity Monitor Beam ~90% ~1.5% ~8%

JLab Physics Seminar Jin Huang 25  New laser ◦ Narrow line width ◦ 3 He ↑P/P ~30%  New optics and oven ◦ Polarizing and polarimetery at 3 directions  Holding magnet field ◦ 3D field hold spin to any direction  A smart target ◦ Flip 3 He spin every 20min ◦ <10 -3 failure rate ◦ Auto analysis, log and early warnings Beam Polarimetry Luminosity Monitor

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 High luminosity: L(n) = cm -2 s -1  Record high 50-65% polarization in beam with automatic spin flip / 20min  = 55.4% ± 0.4% (stat. per spin state) ± 2.7 % (sys.) JLab Physics Seminar Jin Huang 27 Beam Polarimetry Luminosity Monitor

JLab Physics Seminar Jin Huang 28 Beam Polarimetry Luminosity Monitor Detector Hut D1 Q1 Q2 Q3 Detector Package Detector Package

 Detector ◦ Clean e/π separation with Gas Cherenkov counter and Lead- glass detector  Electron contamination in pions <10 -4 ◦ Kaon rejection in pion by: Aerogel Cerenkov with kaon rejection 10:1  Kaon contamination in pion <0.6% ◦ Scintillator: timing σ~150ps JLab Physics Seminar Jin Huang 29 Beam Polarimetry Luminosity Monitor HRS Entrance Beam Vertex e’ Sieve Plate  Spectrometer optics  3D momentum and vertex reconstructions

JLab Physics Seminar Jin Huang 30 Beam Polarimetry Luminosity Monitor  Detects electrons  Single dipole magnet  A “big bite” of acceptance ◦ 64 msr ◦ P : 0.6 ~ 2.2 GeV/c  3 wire chambers: 18 planes for precise tracking  Bipolar momentum reconstruction  Pre-shower and shower for electron PID  Scintillator for coincidence with left HRS

 Optics for both negative and positive charged particles ◦ Chamber resolution: 180um ◦ Angular resolution: < 10 mrad ◦ Momentum resolution: 1% ◦ Vertex resolution: 1 cm  e-pi separation with calorimeters (shower-preshower) ◦ Pion contamination in SIDIS electron <2% JLab Physics Seminar Jin Huang 31 BigBite Sieve Slit Invariant mass of p(e,e’) Electron-pion separation

 Time-of-Flight ◦ Detector: Scintillator planes in both spectrometers ◦ Coincidence timing-of-flight resolution ~ 340ps ◦ proton/π 2.4GeV  Vertex ◦ Coincidence resolution ~ 1cm (Visible Target Length ~ 30cm)  Random background <1% δA≤ 0.3×10 -3 (very minor) JLab Physics Seminar Jin Huang 32 Beam Polarimetry Luminosity Monitor

p T & ϕ h - ϕ S coverage JLab Physics Seminar Jin Huang 33 Kinematics coverage Q 2 >1GeV 2 W>2.3GeV z=0.4~0.6 W’>1.6GeV x bin 1 234

 Frequent beam-target double spin reversals ◦ Cancels single spin related structure function and final state interactions ◦ Cancel sys. uncert. due to acceptance, yield drift, lumi.  Two analysis team ◦ Independent analysis after detector calibration ◦ Blue Team  A local pair-angular bin-fit method ◦ Red Team  Developed maximum likelihood estimator ◦ Result from both team agree well JLab Physics Seminar Jin Huang 34

e  e’e’ BigBite 30 o ~7 o h +/- PTPT STST SLSL 3 He Spin  Target spin perpendicular to initial electron momentum  Small longitudinal target spin parallel to virtual photon -> A LL asymmetry related to helicity PDF  Correction ~ S L * A LL  Estimated using maximum likelihood  Estimation of A LL 1. Global analysis -> A 1 (3He->pi)  A 1 is trans. momentum integrated A LL  Calculated by Dr. R. Sassort (DSSV 2008) 2. A 1 -> A LL by taking account of  Trans. momentum dependence  Long./trans. cross section ratio  Kinematic factor  Other corrections: nitrogen/charge sym. background correction JLab Physics Seminar Jin Huang 35

 First published A LT data  Data suggest non-zero SIDIS A LT : π -, +2.8σ (sum all bins)  First indication of non-zero g 1T therefore non-zero quark OAM interferences JLab Physics Seminar Jin Huang 36 Huang, et. al. PRL. 108, (2012)

 ◦, sensitive to d quark ◦ Dominated by L=0 (S) and L=1 (P) interference  Corrected for proton dilution (unpolarized part) ◦ Measured with dedicated data of unpolarized hydrogen, He-3  Proton asymmetry contribution ◦ Based on the COMPASS preliminary results ◦ Crosschecked with the recent HERMES preliminary results ◦ δA/Δ stat. A ≤12% JLab Physics Seminar Jin Huang 37 ~90% ~1.5% ~8%

 Consistent with models in signs  Suggest larger asymmetry, possible interpretations: ◦ Larger quark spin-orbital interference ◦ different P T dependence ◦ larger subleading-twist effects JLab Physics Seminar Jin Huang 38 Huang, et. al. PRL. 108, (2012)

  -2σ Negative asymmetry observed: JLab Physics Seminar Jin Huang 39 ≈ ≈ Suggest Negative

E A LT on 3 He CLAS A UL on proton JLab Physics Seminar Jin Huang 40 g 1T u > ? 0 d quark in neutron dominant A LT (n→π - ) π+π+ u in proton dominant A LT (n→π - ) u in proton dominant A LT (n→π - ) h 1L < ? 0 ⊥u arXiv:

JLab Physics Seminar Jin Huang 41 Phys. Rev. Lett. 107, (2011)

E & E Fully approved for 12GeV New SoLID spectrometer High lumi. pol. 3 He target Super BigBite CLAS polarized SIDIS program Drell-Yen process in pp, EIC JLab Physics Seminar Jin Huang 42

JLab Physics Seminar Jin Huang 43  Key device to achieve high-precision mapping and minimizing systematics  High Luminosity target and upgraded beam energy -> 12 GeV  Large acceptance: enable 4D-mapping  Full/symmetric azimuthal angular coverage: small systematics  Device shared by three SIDIS experiment and a parity-violation DIS exp.  Budget: ~20M; early design stage; detector prototyping

 3 He(e, e’ π ± )X, continuation and next-generation of 6-GeV measurement ◦ E & E using SoLID, max precision, “A”-rated ◦ E using Super-BigBite, also cover Kaons  p(e, e’ π ± )X, PR conditionally approved, proton target  JLab will lead the world measurement on A LT and knowledge on g 1T function JLab Physics Seminar Jin Huang 44 Center of points: Scale for error bars: E projection neutron A LT of one out of 48 Q 2 -z bins for π -

JLab Physics Seminar Jin Huang 45 Q 2 = 1~8 GeV 2 P h⊥ (GeV/c) z= 0.3~0.7 x bj data point: Projection for neutron A LT of π -

 g 1T can be probed in Drell-Yen process ◦ Azimuthal weighted double spin asymmetry in transverse polarized p – p(p_bar) -> g 1T  EIC: g 1T for sea quarks JLab Physics Seminar Jin Huang 46 Lu, et.al. PhysRevD Azimuthal Weights

 First measurement of 3 He (neutron) A LT ◦ First indication of non-zero A LT ( +2.8 σ π + production on 3 He ) ◦ Suggest non-zero g 1T and Re[(L=0) q × (L=1) q ] ◦ Huang, et. al. PRL. 108, (2012), arXiv:  Systematic uncertainties is minimized by unique fast beam helicity/target spin flip ◦ Cancel systematic effect due to efficiency drift/acceptance/luminosity fluctuation/SSA terms  Foundation for future experiments ◦ Precise mapping of A LT following JLab 12 GeV upgrade ◦ Comprehensive study of spin-orbital correlations JLab Physics Seminar Jin Huang 47

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JLab Physics Seminar Jin Huang 49