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Contalbrigo Marco INFN Ferrara

s tudies (at Jl ab ) of p artonic t ransverse m omentum and s pin s tructure of the n ucleon. Contalbrigo Marco INFN Ferrara. MENU 2013 3 th October 2013, Roma. The Spin D egree of Freedom. e p → e p.

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Contalbrigo Marco INFN Ferrara

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  1. studies (at Jlab) of partonic transverse momentum and spin structure of the nucleon Contalbrigo Marco INFN Ferrara MENU 2013 3th October 2013, Roma

  2. The Spin Degree of Freedom e p → e p Spin degrees of freedom can explain otherwise surprising phenomena and bring new insights into nuclear matter structure e p → e p PRC 68, 034325 (2003) xF MENU2013, 3rd October 2013, Roma Contalbrigo M. 2

  3. The Spin Degree of Freedom In our exploration of the QCD micro-world Fundamental: do not neglect spin !! Two questions in Hadronic Physics await explanation since too long Single Spin Asymmetries Proton Spin Budget AN ? √s = 20 GeV pT< 2 GeV/c xF MENU2013, 3rd October 2013, Roma Contalbrigo M. 3

  4. Quantum Phase-space Distributions of Quarks Wpq(x,kT,r) “Mother” Wigner distributions Probability to find a quarkqin a nucleon P with a certain polarization in a position r &momentum k d3r d2kT (FT) TMD PDFs: fpu(x,kT),… GPDs: Hpu(x,x,t), … Semi-inclusive measurements Momentum transfer to quark Direct info about momentum distribution Exclusive Measurements Momentum transfer to target Direct info about spatial distribution x=0,t=0 d2kT May explain SSA & Lam-Tung May solve proton spin puzzle √s = 20 GeV PDFs fpu(x),… AN pT< 2 GeV/c xF MENU2013, 3rd October 2013, Roma Contalbrigo M. 4

  5. A World-wide Challenge EIC MENU2013, 3rd October 2013, Roma Contalbrigo M. 5

  6. The SIDIS Landscape Limit defined by luminosity Different Q2 for same x range Your Text Here EIC 1034 1032 1031 1035 Complementary experiments Valence Sea MENU2013, 3rd October 2013, Roma Contalbrigo M. 6

  7. The JLAB12 Facility

  8. CEBAF Upgrade at Jefferson Lab add Hall D (and beam line) Upgrade magnets and power supplies CHL-2 Enhance equipment in existing halls Beam Energy 12 GeV Beam current 90 mA Beam polarization 85 % MENU2013, 3rd October 2013, Roma Contalbrigo M. 8

  9. JLab12 Experimental Halls Hall-C Super High Momentum Spectrometer (SHMS) unpolarized SIDIS, hadron ID Hall-A Spectrometer Pair, polarized 3He target up to to 1038 cm-2 s-1hadron ID Hall-A Hall-B SOLID3He, NH3 polarized targets up to 1036 cm-2 s-1large acceptance, pion ID CLAS12 H,D polarized targets up to 1035 cm-2 s-1 “complete” acceptance, hadron ID MENU2013, 3rd October 2013, Roma Contalbrigo M. 11

  10. The Hall-C High-momentum Spectrometers SIDIS cross-section factorization tests HMS 7 GeV/c spectrometer 10o-90o angular range e/h, p/K ID by Cherenkov Super-HMS 11 GeV/c spectrometer 5o-25o angular range e/h, p/K ID by Cherenkov MENU2013, 3rd October 2013, Roma Contalbrigo M. 12

  11. The CLAS12 Large-Acceptance Spectrometer FTOF DC R3 R2 R1 Luminosity up to 1035 cm-2 s-1 Highly polarized electron beam EC RICH H and D polarized targets Broad kinematic range coverage (current to target fragmentation) TOF + RICH for clear hadron ID HTCC PCAL Solenoid Torus TMDs and GPDs comprehensive study, with special care on applicability MENU2013, 3rd October 2013, Roma Contalbrigo M. 13

  12. CLAS12 Kinematic Coverage p+ acceptance Electron Large electron scattering angles (> 20o) mandatory to reach high Q2 values Intermediate anguar range (15-25o) mandatory to reach high PT values Electron The CLAS12 forward detector is perfectly suitable for high-Q2 and high-pT measurements since designed to cover up to 40 degrees angles MENU2013, 3rd October 2013, Roma Contalbrigo M. 14

  13. Transversely Polarized HD-Ice Target HD-Ice target vsstandard nuclear targets (less luminosity for higher purity) • Advantages: • Minimize nuclear background • smaller dilution, no attenuation at large pT • Weak holding field (BdL~ 0.1 Tm) • wide acceptance, negligible beam deflection • Disadvantages: • Very long polarizing times (months) • Sensitivity to local heating by charged beams R Ph2 T HD-ice ran from Nov/11 to May/12 at Jlab R&D work required to run with electron beams E06-101 up to 108g/s T1 ~ years MENU2013, 3rd October 2013, Roma Contalbrigo M. 15

  14. The Hall-A High-Luminosity Spectrometers Present: spectrometer pair High-luminosity 3He target GEM trackers PID challenging Future: large acceptance detector up to 1036 cm-2 s-1 large acceptance, pion ID up to to 1038 cm-2 s-1 hadron ID high Q2 Ultimate statistical precision in the valence region MENU2013, 3rd October 2013, Roma Contalbrigo M. 16

  15. Polarize 3He Target MENU2013, 3rd October 2013, Roma Contalbrigo M. 17

  16. The SIDIS Case Number Helicity quark polarisation SIDIS cross section (transversely pol. target): Boer-Mulders Density TMD factorization for PT<<Q nucleon polarisation Worm-gear Transversity Involved phenomenology due to the convolution over transverse momentum Sivers Worm-gear Pretzelosity FF DF MENU2013, 3rd October 2013, Roma Contalbrigo M. 18

  17. Number Helicity Number Density (TheBaseline) Boer-Mulders Density nucleon polarisation Worm-gear Transversity Sivers Worm-gear Pretzelosity

  18. Parton Number Density ATLAS: arXiv:1206.4051 MENU2013, 3rd October 2013, Roma Contalbrigo M. 20

  19. Parton Number Density SIDIS extraction: Jackson, DIS 2013 E12-07-104 Hall-B ATLAS: arXiv:1206.4051 MENU2013, 3rd October 2013, Roma Contalbrigo M. 21

  20. The Ph-unintegratedmultiplicities T arXiv: 1305.7317 Ph Disentanglement of z and : access to the transverse intrinsic quark kT and fragmentation pT, i.e. from gaussiananstaz T 2 Ph T Ph Scimemi, DIS 2013 Joosten, DIS 2011 T Flavor Structure of the Nucleon Sea, 1st July 2013, ECT* Contalbrigo M. 22

  21. Ph Dependence T Map pfpT dependence for pion off proton and deuteron targets E12-09-017 Hall-C At pT> 0.2 GeV/c use dependencies measured in CLAS12 experiment Hall C - JLab MENU2013, 3rd October 2013, Roma Contalbrigo M. 23

  22. Longitudinal Cross-section Cornell data of 70’s To be accounted in any TMD asymmetry interpretation E12-06-104 Hall-C RDIS0 at Q2∞ due to scattering off spin-½ quarks RDIS sensitive to gluon and higher-twist effects RSIDIS(z,pT) = un-integrated RDIS MENU2013, 3rd October 2013, Roma Contalbrigo M. 24

  23. Number Helicity CaHn & Boer-mulders (TheNeglected Effects) Naïve-T-odd Chirally-odd Spin effect in unpolarized reactions Boer-Mulders Density nucleon polarisation Worm-gear Transversity Sivers Worm-gear Pretzelosity

  24. The Azimuthal Modulation E615 NA10 E866 EMC (1987) Kinematical effect predicted since 1978 by Cahn due to non-zero intrinsic kT Cahn PLB 78 (1978) Leading-twist contribution introduced by Boer & Mulders in 1998 Boer & Mulders PRD 57 (1998) • No hadron identification • No charge separation • Poor statistics for cos2f SIDIS: qualitative agreement with Cahn expectations till 2008 DY: violation of Lam-Tung relation Non perturbative contribution PT (GeV/c) MENU2013, 3rd October 2013, Roma Contalbrigo M. 26

  25. Unpolarized Cross-section cos2f non-zero ! Difference in hadron charge ! Positive for p- Negative for p+ HERMES H & D DATA [PRD 87 (2013) 012010] Quark d vs u contribution ? DATA support Boer-Mulders of same sign for u and d MENU2013, 3rd October 2013, Roma Contalbrigo M. 27

  26. The SIDIS cos2fpT dependence Can be explained by large uncertainty on Cahn and neglected HT effects ? [arXiv: 0912.5194] MENU2013, 3rd October 2013, Roma Contalbrigo M. 28

  27. Unpolarized Target Measurements of kinematic (x,Q2,z,PT) will probe HT distribution functions In the perturbative limit 1/PTbehavior expected ALU~ 1/Q (Twist-3) Perturbative region Collinear factorization E12-06-112 Hall-B Non-perturbative TMD factorization MENU2013, 3rd October 2013, Roma Contalbrigo M. 29

  28. The SIDIS cos2fpT dependence ep e’ KX E12-09-008 Hall-B kaon Boer-Mulders spin-orbit effect E12-06-112 Hall-B MENU2013, 3rd October 2013, Roma Contalbrigo M. 30

  29. Number Helicity Helicity (TheFirst Puzzle) Boer-Mulders Density nucleon polarisation Worm-gear Transversity Sivers Worm-gear Pretzelosity

  30. Parton Helicity from SIDIS COMPASS [arXiv:1007.4061] HERMES [hep-ex/0407032] -- DSSV -- GRSV -- BB HERMES [arXiv:0803.2993] -- LSS MENU2013, 3rd October 2013, Roma Contalbrigo M. 32

  31. Sea Parton Helicity from RHIC DSSV++ [arXiv:1304.0079] Seidl talk Flavor Structure of the Nucleon Sea, 1st July 2013, ECT* Contalbrigo M. 33

  32. Gluon Parton Helicity from RHIC DSSV++ [arXiv:1304.0079] Flavor Structure of the Nucleon Sea, 1st July 2013, ECT* Contalbrigo M. 34

  33. Quark Helicity at High-x E12-07-104 Hall-B MENU2013, 3rd October 2013, Roma Contalbrigo M. 35

  34. Quark Helicity Transverse momentum dependence of quark helicityvs number density Quark helicity at high-x is sensitive to orbital angular momentum. E12-07-104 Hall-B E12-06-109 Hall-B E12-06-110 Hall-C E12-06-122 Hall-A MENU2013, 3rd October 2013, Roma Contalbrigo M. 36

  35. Number Helicity Transversity (the Collinear Missing piece) Chirally-odd Boer-Mulders Density First evidence: 2005 nucleon polarisation Worm-gear Transversity Sivers Worm-gear Pretzelosity + - + -

  36. The Collins Amplitude Hall A [arXiv:1106.0363] HERMES [arXiv:1006.4221] COMPASS combined 2007 – 2010 results Martin at DIS13 MENU2013, 3rd October 2013, Roma Contalbrigo M. 38

  37. Transversity Signals • Existingdata limitedto x < 0.3 • FF evol.. from high energy colliders 1stextraction of Transversity! d u xh1(x) xh1(x) Anselmino ++ arXiv: 1303.3822 MENU2013, 3rd October 2013, Roma Contalbrigo M. 39

  38. Transversity Signals • Existingdata limitedto x < 0.3 • FF evol.. from high energy colliders Collinear extraction ! 1stextraction of Transversity! d u xh1(x) xh1(x) x x Bacchetta ++ arXiv: 1206.1836 Anselmino ++ arXiv: 1303.3822 MENU2013, 3rd October 2013, Roma Contalbrigo M. 40

  39. Transversity @ JLab12 Large x important to constrain the tensor charge C12-11-111 Hall-B Proton Di-hadron channel for h1 Test of TMDs extraction E12-12-109 Hall-B MENU2013, 3rd October 2013, Roma Contalbrigo M. 41

  40. Number Helicity Sivers (The TMD challenge) Naïve-T-odd Non-trivial gauge link Process dependence Boer-Mulders Density nucleon polarisation Worm-gear Transversity Sivers Worm-gear Pretzelosity + + + -

  41. The Sivers Signals Clear not-zero signals COMPASS, arXiv: 1205.5122 HERMES, arXiv: 0906.3918 Systematic shift: Sivers Q2 evolution ? K+ amplitudes larger than π+: HERMES [arXiv:0906.3918] combined 2007 – 2010 results K+-p+ K+ K- MENU2013, 3rd October 2013, Roma Contalbrigo M. 43

  42. The Sivers Distributions Without sea: With sea: [arXiv:1012.3565] Not zero ? 44 MENU2013, 3rd October 2013, Roma Contalbrigo M.

  43. The SiversChallenge arXiv: 1107.4446 From SIDIS to Drell-Yan: Sign change as a crucial test of TMDs factorization x MENU2013, 3rd October 2013, Roma Contalbrigo M. 45

  44. The SiversChallenge arXiv: 1107.4446 From SIDIS to Drell-Yan: Sign change as a crucial test of TMDs factorization x p p @ Brookhaven p H @ CERN MENU2013, 3rd October 2013, Roma Contalbrigo M. 46

  45. OAM Glimpses Inconsistency in DATA ? Diehl et al. arXiv: 1302.4604 Bacchetta et al. arXiv: 1107.5755 MENU2013, 3rd October 2013, Roma Contalbrigo M. 47

  46. Sivers @ JLab12 HDice C12-11-111 Hall-B 3He )X 40 days E12-11-007 Hall-A E12-10-006 Hall-A E12-11-108 NH3 &3He Proton SOLID (projected) MENU2013, 3rd October 2013, Roma Contalbrigo M. 48

  47. Multi-D Analysis Statistical errors 4D analysis on p+ MENU2013, 3rd October 2013, Roma Contalbrigo M. 49

  48. The JLab12 Charge Start of Accelerator commissioning expected in November and running beam to Hall-A in February 2014 Complete mapping (3D) of the nucleon in the valence region High potential of the complementary programs of 3 experimental halls MENU2013, 3rd October 2013, Roma Contalbrigo M. 50

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